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Journal of Iron and Steel Research International 2024年第8期31卷 2031-2040页

作者： Ting Dai De-yu gu Yu-wen Qiu Wei guo Hui Ding yi-wei Sun School of Materials Science and Engineering Jiangsu Key Laboratory of Advanced Metallic MaterialsSoutheast UniversityNanjing 211189JiangsuChina

The effect of spatial temperature gradient on the microstructural evolution of a 308L stainless steel during the directed energy deposition(DED)process was experimentally investigated.A novel cooling system was designed and incorporated to a DED system in order to control the temperature gradient along the deposition direction during *** deposition,the workpiece was placed on a lifting platform,and as the deposition process proceeded,the platform and workpiece were gradually lowered into cooling water so that the temperature gradient along the deposition direction could be controlled and maintained stable during the deposition *** microstructure characterization results indicated that a deposition strategy with higher G and G/R values(where G is temperature gradient and R is solidification rate)produced finer cellular grains that were better aligned with the deposition direction,while a deposition strategy with lower G and G/R values produced columnar grains with larger primary arm spacing and less aligned with the deposition direction.

关键词： Additive manufacturing Directed energy deposition Stainless steel Microstructure Temperature gradient

Hierarchical Disturbance Propagation Mechanism and Improved Contract Net Protocol for Satellite TT&C Resource Dynamic Scheduling

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Complex System Modeling and Simulation 2024年第2期4卷 166-183页

作者： Zhiqing Xiang yi gu Xinwei Wang guohua Wu the School of Traffic and Transportation Engineering Central South UniversityChangsha 410075China the School of Engineering and Materials Science Queen Mary University of LondonLondonE14NSUK the School of Automation Central South UniversityChangsha 410083China

The practical engineering of satellite tracking telemetry and command(TT&C)is often disturbed by unpredictable external factors,including the temporary rise in a significant quantity of satellite TT&C tasks,temporary failures and failures of some TT&C resources,and so *** improve the adaptability and robustness of satellite TT&C systems when faced with uncertain dynamic disturbances,a hierarchical disturbance propagation mechanism and an improved contract network dynamic scheduling method for satellite TT&C resources were designed to address the dynamic scheduling problem of satellite TT&C ***,the characteristics of the dynamic scheduling problem of satellite TT&C resources are analyzed,and a mathematical model is established with the weighted optimization objectives of maximizing the revenue from task completion and minimizing the degree of plan ***,a bottom-up distributed dynamic collaborative scheduling framework for satellite TT&C resources is proposed,which includes a task layer,a resource layer,a central internal collaboration layer,and a central external collaboration *** disturbances are propagated layer by layer from the task layer to the central external collaboration layer in a bottom-up manner,using efficient heuristic strategies in the task layer and the resource layer,*** use improved contract network algorithms in the center internal collaboration layer and the center external collaboration layer,the original scheduling plan is quickly adjusted to minimize the impact of disturbances while effectively completing dynamic task ***,a large number of simulation experiments were carried out and compared with various comparative *** results show that the proposed algorithm can effectively improve the solution effect of satellite TT&C resource dynamic scheduling problems,and has good application prospects.

关键词： satellite tracking telemetry and command(TT&C) dynamic resource scheduling bottom-up mechanism heuristic strategy contract net protocol algorithm

Development and validation of a nomogram to predict allograft survival after pediatric liver transplantation

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World Journal of Pediatrics 2024年第3期20卷 239-249页

作者： guang-Xiang gu Shu-Ting Pan yi-Chen Fan Chen Chen Qiang Xia Department of Liver Surgery Renji HospitalShanghai Jiaotong University School of MedicineNo.160 Pujian RoadPudong New DistrictShanghai 200128China Department of Liver Transplantation Sun Yet-Sen Memorial HospitalSun Yat-Sen UniversityNo.107 Yanjiang West RoadGuangzhou 510080China Clinical Center for Investigation Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina Department of Anesthesiology Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina

Background Liver transplantation is the main treatment for cholestatic liver disease and some metabolic liver diseases in ***,no accurate prediction model to determine the survival probability of grafts prior to surgery *** study aimed to develop an effective prognostic model for allograft survival after pediatric liver *** This retrospective cohort study included 2032 patients who underwent pediatric liver transplantation between January 1,2006,and January 1,2020.A nomogram was developed using Cox regression and validated based on bootstrap *** and discriminatory accuracies were determined using the concordance index and visualized using calibration curves;net benefits were calculated for model *** online Shiny application was developed for easy access to the *** Multivariable analysis demonstrated that preoperative diagnosis,recipient age,body weight,graft type,preoperative total bilirubin,interleukin-1β,portal venous blood flow direction,spleen thickness,and the presence of heart disease and cholangitis were independent factors for survival,all of which were selected in the *** of the nomogram indicated that the 1-,3-,and 5-year predicted survival rates agreed with the actual survival *** concordance indices for graft survival at 1,3,and 5 years were 0.776,0.757,and 0.753,respectively,which were significantly higher than those of the Pediatric End-Stage Liver Disease and Child-Pugh scoring *** allograft dysfunction risk of a recipient could be easily predicted using the following URL:https://***/ASPELT/l Conclusion The allograft survival after pediatric liver transplantation(ASPELT)score model can effectively predict the graft survival rate after liver transplantation in children,providing a simple and convenient evaluation method for clinicians and patients.

关键词： Allograft survival Nomogram Pediatric liver transplantation

Retinal Vessel Segmentation via Adversarial Learning and Iterative Refinement

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Journal of Shanghai Jiaotong university(Science) 2024年第1期29卷 73-80页

作者：顾闻徐奕 School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Retinal vessel segmentation is a challenging medical task owing to small size of dataset,micro blood vessels and low image *** address these issues,we introduce a novel convolutional neural network in this paper,which takes the advantage of both adversarial learning and recurrent neural *** iterative design of network with recurrent unit is performed to refine the segmentation results from input retinal image *** unit preserves high-level semantic information for feature reuse,so as to output a sufficiently refined segmentation map instead of a coarse ***,an adversarial loss is imposing the integrity and connectivity constraints on the segmented vessel regions,thus greatly reducing topology errors of *** experimental results on the DRIVE dataset show that our method achieves area under curve and sensitivity of 98.17%and 80.64%,*** method achieves superior performance in retinal vessel segmentation compared with other existing state-of-the-art methods.

关键词： medical image processing retinal image segmentation adversarial learning iterative refinement

Establishing and clinically validating a machine learning model for predicting unplanned reoperation risk in colorectal cancer

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World Journal of Gastroenterology 2024年第23期30卷 2991-3004页

作者： Li-qun Cai Da-Qing Yang Rong-Jian Wang He Huang yi-Xiong Shi Department of Colorectal and Anal Surgery Whenzhou Central HospitalWenzhou 325000Zhejiang ProvinceChina Department of Colorectal and Anorectal Surgery The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

BACKGROUND Colorectal cancer significantly impacts global health,with unplanned reoperations post-surgery being key determinants of patient *** predictive models for these reoperations lack precision in integrating complex clinical *** To develop and validate a machine learning model for predicting unplanned reoperation risk in colorectal cancer *** Data of patients treated for colorectal cancer(n=2044)at the First Affiliated Hospital of Wenzhou Medical University and Wenzhou Central Hospital from March 2020 to March 2022 were retrospectively *** were divided into an experimental group(n=60)and a control group(n=1984)according to unplanned reoperation *** were also divided into a training group and a validation group(7:3 ratio).We used three different machine learning methods to screen characteristic variables.A nomogram was created based on multifactor logistic regression,and the model performance was assessed using receiver operating characteristic curve,calibration curve,Hosmer-Lemeshow test,and decision curve *** risk scores of the two groups were calculated and compared to validate the *** More patients in the experimental group were≥60 years old,male,and had a history of hypertension,laparotomy,and hypoproteinemia,compared to the control *** logistic regression analysis confirmed the following as independent risk factors for unplanned reoperation(P<0.05):Prognostic Nutritional Index value,history of laparotomy,hypertension,or stroke,hypoproteinemia,age,tumor-node-metastasis staging,surgical time,gender,and American Society of Anesthesiologists *** operating characteristic curve analysis showed that the model had good discrimination and clinical *** This study used a machine learning approach to build a model that accurately predicts the risk of postoperative unplanned reoperation in patients with colorectal cancer,which can improve tr

关键词： Colorectal cancer Postoperative unplanned reoperation Unplanned reoperation Clinical validation Nomogram Machine learning models

Optimizing FeCoNiCrTi high-entropy alloy with hydrogen pumping effect to boost de/hydrogenation performance of magnesium hydride

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Rare Metals 2024年第7期43卷 3273-3285页

作者： Meng-Chen Song Fu-ying Wu yi-qun Jiang Xiu-Zhen Wang Hu Zhao Li-Xin Chen Liu-Ting Zhang School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and TechnologyZhenjiang 212003China Max Planck Institute for Iron Research 40237DuisseldorfGermany School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

The exploration of efficient,long-lived and cost-effective transition metal catalysts is highly desirable for the practical hydrogen storage of magnesium hydride(MgH_(2)) in sustainable energy ***,FeCoNiCrTi high-entropy alloy(HEA) nanosheets were prepared via a facile wet chemical ball milling strategy and they were introduced into MgH_(2) to boost the hydrogen storage *** refined HEA exhibited superior catalytic activity on MgH_(2).In contrast to additive-free MgH_(2),the initial desorption temperature of the constructed MgH_(2)-HEA composite was reduced from 330.0 to 198.5℃ and a remarkable 51% reduction in the dehydrogenation activation energy was ***,the MgH_(2)-HEA composite only required one-twentieth time of that consumed by pure MgH_(2) to absorb 5.0 wt% of H_(2) at 225℃.The synergy between the "hydrogen pumping" effect of Mg_2Ni/Mg_2NiH_4 and Mg_2Co/Mg_2CoH_5 couples,as well as the good dispersion of Fe,Cr and Ti on the surface of MgH_(2) contributed to the enhanced de/hydrogenation performance of the MgH_(2)-HEA *** study furnishes important steering for the design and fabrication of multiple transition metal catalysts and may push the commercial application of magnesium-based hydrides one step forward.

关键词： Hydrogen storage Magnesium hydride High-entropy alloys Catalysis

Health risk assessment of heavy metal pollution in groundwater of a karst basin,SW China

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Journal of Groundwater Science and Engineering 2024年第1期12卷 49-61页

作者： Fu-ning Lan yi Zhao Jun Li Xiu-qun Zhu Karst Ecosystem National Observation and Research StationPingguo 531406GuangxiChina Institute of Karst Geology International Research Centre on KarstUnder the Auspices of UNESCOGuangxi Karst Resources and Environment Research Center of Engineering TechnologyChinese Academy of Geological SciencesKarst Dynamics LaboratoryMNR and GuangxiGuilin 541004China Hebei Key Laboratory of Water Quality Engineering and Comprehensive Utilization of Water Resources Hebei University of ArchitectureZhangjiakou 075000Hebei ProvinceChina College of Hydrology and Water Resources Hohai UniversityNanjing 210098China

To investigate the presence of metal elements and assess their health risk for the populace in the Nandong Underground River Basin(NURB),we conducted an analysis of eleven common heavy metals in the water body.A Health risk assessment(HRA)model was employed to analyze 84 water samples from the *** detection results revealed the following order of heavy metals concentrations:Fe>Al>Mn>Zn>As>Cd>Pb>Cr>Ni>Cu>*** analysis indicated a certain similarity in material source and migration transformation among these eleven metal *** study identified that the health risks for local residents exposed to metal elements in the water of NURB primarily stem from carcinogenic risk(10^(−6)–10^(−4)a^(−1))through the drinking water ***,the health risk of heavy metal exposure for children through drinking water was notably higher than for *** maximum health risks of Cr in both underground and surface water exceeded the recommendation standard(5.0×10^(−5)a^(−1))from ICRP,surpassing the values recommended by the Swedish Environmental Protection Agency,the Dutch Ministry of Construction and Environment and the British Royal Society(5.0×10^(−6)a^(−1)).The results of the health risk assessment indicate that Cr in the water of NURB is the primary source of carcinogenic risk for local residents,followed by Cd and ***,it is imperative to control these three carcinogenic metals when the water was used as drinking water resource.

关键词： Water Pollution Correlation Analysis Toxicity of Heavy Metal Elements Underground River Basin Carcinogenicity Potential

Chemokine platelet factor 4 accelerates peripheral nerve regeneration by regulating Schwann cell activation and axon elongation

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Neural Regeneration Research 2024年第1期19卷 190-195页

作者： Miao gu Xiao Cheng Di Zhang Weiyan Wu yi Cao Jianghong He Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education Co-innovation Center of NeuroregenerationNMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongJiangsu ProvinceChina School of Basic Medical Sciences Hebei Key Laboratory of Nerve Injury and RepairChengde Medical UniversityChengdeHebei ProvinceChina

Schwann cells in peripheral nerves react to traumatic nerve injury by attempting to grow and *** r,it is unclear what factors play a role in this *** this study,we searched a GEO database and found that expression of platelet factor 4 was markedly up-regulated after sciatic nerve *** factor is an important molecule in cell apoptosis,diffe rentiation,survival,and ***,polymerase chain reaction and immunohistochemical staining confirmed the change in platelet factor 4 in the sciatic nerve at different time points after ***-linked immunosorbent assay confirmed that platelet factor 4 was secreted by Schwann *** also found that silencing platelet factor 4 decreased the proliferation and migration of primary cultured Schwann cells,while exogenously applied platelet factor 4 stimulated Schwann cell prolife ration and migration and neuronal axon ***,knocking out platelet factor 4 inhibited the prolife ration of Schwann cells in injured rat sciatic *** findings suggest that Schwann cell-secreted platelet factor 4 may facilitate peripheral nerve repair and regeneration by regulating Schwann cell activation and axon ***,platelet factor 4 may be a potential therapeutic target for traumatic peripheral nerve injury.

关键词： axon elongation bioinformatic analysis cell migration cell proliferation dorsal root ganglia peripheral nerve regeneration peripheral nerve trauma platelet factor 4 rat sciatic nerve Schwann cells

Texture and Se vacancy optimization induces high thermoelectric performance in Bi_(2)Se_(3) flexible thin films

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Rare Metals 2024年第6期43卷 2796-2804页

作者： Dong-Wei Ao Wei-Di Liu Yue-Xing Chen Fan Ma yi-Jie gu Zhuang-Hao Zheng School of Machinery and Automation Weifang UniversityWeifang 261061China Australian Institute for Bioengineering and Nanotechnology The University of QueenslandBrisbane 4072Australia Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China

Bi_(2)Se_(3)-based flexible thin film with high thermoelectric performance is promising for the waste heat recovery *** this work,a novel post-selenization method is employed to prepare n-type Bi_(2)Se_(3)flexible thin films with highly textured *** strengthened texture and Se vacancy optimization can be simultaneously achieved by optimizing the selenization *** highly oriented texture leads to the increased carrier mobility and results in a high electric conductivity of~290.47 S·cm^(-1)at 623 ***,a high Seebeck coefficient(>110μW·K-1)is obtained due to the reduced carrier concentration,induced by optimizing vacancy ***,a high power factor of 3.49μW·cm^(-1)·K^(-2)at 623 K has been achieved in asprepared highly-bendable Bi_(2)Se_(3)flexible thin films selenized at 783 *** study introduces an effective post-selenization method to tune the texture structure and vacancies of Bi_(2)Se_(3)flexible thin films,and correspondingly achieves high thermoelectric performance.

关键词： Thermoelectric Bi_(2)Se_(3) Flexible thin film Post-selenization

Differential bonding behaviors of sodium/potassium-ion storage in sawdust waste carbon derivatives

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Chinese Chemical Letters 2024年第4期35卷 496-501页

作者： Jun-Ming Cao Kai-Yang Zhang Jia-Lin Yang Zhen-yi gu Xing-Long Wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China Department of Chemistry Northeast Normal UniversityChangchun 130024China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) are the most promising alternatives to lithium-ion batteries, and thus have drawn intensive research attention. Porous carbon materials from different precursors have been widely used as anode materials owing to their compatible storage effectiveness of both larger radii sodium and potassium ions. However, the differential bonding behaviors of Na and K ions with porous carbon-based anode are the significant one worth investigating, which could provide a clean picture of alkali ions storage mechanism. Therefore, in this work, we prepare a porous carbon network derived from sawdust(SDC) wastes, to further analyze the differences on sodium and potassium ions storage behaviors in terms of bond-forming process. It is found that, as-prepared SDC anodes could deliver stable sodium and potassium storage capacities, however, there are notable distinctions in terms of electrochemical behaviors and diffusion processes. By virtue of ex-situ XRD and Raman spectroscopy, the phase transition reaction of potassium ions could be well-observed, and the results shows that the multiple intercalated compounds was formed in SDC network during ions insertion, further resulting in slower diffusion kinetics and larger resistance compared to non-bonded process of sodium ions storage. This study provides more insights into the differences between sodium and potassium ions storage, as well as the energy storage mechanism of porous carbon as anodes for secondary batteries.

关键词： Porous carbon Sodium-ion storage Potassium-ion storage Bonding behaviors Batteries