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Influence of sintering time on microstructure and properties of hot oscillatory pressing sintered W–Cu refractory alloys

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Tungsten 2024年第2期6卷 323-332页

作者： Zi-Qian Wu Wei Zhao Ka Gao shi-Hao Du Qing-quan Kong De-Jian Sun Yang Gao School of Materials Science and Engineering Zhengzhou University of AeronauticsZhengzhou 450015China School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China Department of General Medicine Changhai HospitalShanghai 200000China Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan 430081China Sichuan Province Engineering Technology Research Center of Powder Metallurgy Chengdu UniversityChengdu 610106China

W–Cu refractory alloys are widely used in aerospace,aviation,electronics,power,and other fi elds.However,because of its large melting point diff erence between alloy elements,the conventional powder metallurgy method required a long time of high temperature sintering is very likely to cause low density and abnormal grain size growth.Therefore,90W-10Cu refractory alloys were successfully prepared by hot oscillatory pressing(HOP)under diff erent sintering time in this work.Then the infl uence of sintering time on the microstructure,grain size,density,Vickers hardness,room-tensile property,and electrical conductivity of the W–Cu refractory alloy was systematically invested.The results showed that during the short sintering time(30–90 min),the density,Vickers hardness,tensile strength,and electrical conductivity of the W–Cu refractory alloy increased signifi cantly to 98.7%,163.29 HV 30,507.3 MPa,and 14.2%International Annealed Copper Standard with the sintering time increasing,respectively,while its grain size showed no obvious change.When the sintering time further increased to 120 min,the density was basically consistent with the sintering time of 90 min.Nevertheless,the prolonged high temperature sintering resulted in the grain growth of the samples,which caused the deterioration of the Vickers hardness,room-tensile strength,and conductivity properties of the W–Cu refractory alloy.At the same sintering time,the density,Vickers hardness,and electrical conductivity of the HOP sintered W–Cu refractory alloy were signifi cantly higher than those of the HP sintered sample.It was indicated that high density,fi ne-grain,and excellent properties W–Cu refractory alloys could be prepared by hot oscillatory pressing under appropriate sintering time.

关键词： W–Cu refractory alloy Hot oscillatory pressing Sintering time Microstructure Property

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Comparing short-term outcomes of robot-assisted and conventional laparoscopic total mesorectal excision surgery for rectal cancer in elderly patients

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1271-1279页

作者： Hao Yang Gang Yang Wen-Ya Wu Fang Wang Xue-quan Yao xiao-Yu Wu The Affiliated Hospital of Nanjing University of Chinese Medicine Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Surgical Oncology The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina

BACKGROUND Da Vinci Robotics-assisted total mesorectal excision(TME)surgery for rectal cancer is becoming more widely used.There is no strong evidence that roboticassisted surgery and laparoscopic surgery have similar outcomes in elderly patients with TME for rectal cancer.AIM To determine the improved oncological outcomes and short-term efficacy of robot-assisted surgery in elderly patients undergoing TME surgery.METHODS A retrospective study of the clinical pathology and follow-up of elderly patients who underwent TME surgery at the Department of Gastrointestinal Oncology at the Affiliated Hospital of Nanjing University of Chinese Medicine was conducted from March 2020 through September 2023.The patients were divided into a robotassisted group(the R-TME group)and a laparoscopic group(the L-TME group),and the short-term efficacy of the two groups was compared.RESULTS There were 45 elderly patients(≥60 years)in the R-TME group and 50 elderly patients(≥60 years)in the L-TME group.There were no differences in demographics,conversion rates,or postoperative complication rates.The L-TME group had a longer surgical time than the R-TME group[145(125,187.5)vs 180(148.75,206.25)min,P=0.005),and the first postoperative meal time in the L-TME group was longer than that in the R-TME(4 vs 3 d,P=0.048).Among the sex and body mass index(BMI)subgroups,the R-TME group had better out-comes than did the L-TME group in terms of operation time(P=0.042)and intraoperative assessment of bleeding(P=0.042).In the high BMI group,catheter removal occurred earlier in the R-TME group than in the L-TME group(3 vs 4 d,P=0.001),and autonomous voiding function was restored.CONCLUSION The curative effect and short-term efficacy of robot-assisted TME surgery for elderly patients with rectal cancer are similar to those of laparoscopic TME surgery;however,robotic-assisted surgery has better short-term outcomes for individuals with risk factors such as obesity and pelvic stenosis.Optimizing the learning curve can shorten the operation time,reduce the

关键词： Robotic surgery Laparoscopy Rectal cancer Total mesorectal excision Elderly

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Is recovery enhancement after gastric cancer surgery really a safe approach for elderly patients?

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1334-1343页

作者： Zi-Wei Li xiao-Juan Luo Fei Liu Xu-Rui Liu Xin-Peng Shu Yue Tong quan Lv xiao-Yu Liu Wei Zhang Dong Peng Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Endoscopy Center The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400012China

BACKGROUND This study aimed to evaluate the safety of enhanced recovery after surgery(ERAS)in elderly patients with gastric cancer(GC).AIM To evaluate the safety of ERAS in elderly patients with GC.METHODS The PubMed,EMBASE,and Cochrane Library databases were used to search for eligible studies from inception to April 1,2023.The mean difference(MD),odds ratio(OR)and 95%confidence interval(95%CI)were pooled for analysis.The quality of the included studies was evaluated using the Newcastle-Ottawa Scale scores.We used Stata(V.16.0)software for data analysis.RESULTS This study consists of six studies involving 878 elderly patients.By analyzing the clinical outcomes,we found that the ERAS group had shorter postoperative hospital stays(MD=-0.51,I2=0.00%,95%CI=-0.72 to-0.30,P=0.00);earlier times to first flatus(defecation;MD=-0.30,I²=0.00%,95%CI=-0.55 to-0.06,P=0.02);less intestinal obstruction(OR=3.24,I2=0.00%,95%CI=1.07 to 9.78,P=0.04);less nausea and vomiting(OR=4.07,I2=0.00%,95%CI=1.29 to 12.84,P=0.02);and less gastric retention(OR=5.69,I2=2.46%,95%CI=2.00 to 16.20,P=0.00).Our results showed that the conventional group had a greater mortality rate than the ERAS group(OR=0.24,I2=0.00%,95%CI=0.07 to 0.84,P=0.03).However,there was no statistically significant difference in major complications between the ERAS group and the conventional group(OR=0.67,I2=0.00%,95%CI=0.38 to 1.18,P=0.16).CONCLUSION Compared to those with conventional recovery,elderly GC patients who received the ERAS protocol after surgery had a lower risk of mortality.

关键词： Enhanced recovery after surgery Gastric cancer Elderly Mortality

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Incremental Data Stream Classification with Adaptive Multi-Task Multi-View Learning

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Big Data Mining and Analytics 2024年第1期7卷 87-106页

作者： Jun Wang Maiwang shi xiao Zhang Yan Li Yunsheng Yuan Chengei Yang Dongxiao Yu School of Computer Science and Technology Shandong UniversityQingdao 266237China School of Software Shandong UniversityJinan 250101China

With the enhancement of data collection capabilities,massive streaming data have been accumulated in numerous application scenarios.Specifically,the issue of classifying data streams based on mobile sensors can be formalized as a multi-task multi-view learning problem with a specific task comprising multiple views with shared features collected from multiple sensors.Existing incremental learning methods are often single-task single-view,which cannot learn shared representations between relevant tasks and views.An adaptive multi-task multi-view incremental learning framework for data stream classification called MTMVIS is proposed to address the above challenges,utilizing the idea of multi-task multi-view learning.Specifically,the attention mechanism is first used to align different sensor data of different views.In addition,MTMVIS uses adaptive Fisher regularization from the perspective of multi-task multi-view learning to overcome catastrophic forgetting in incremental learning.Results reveal that the proposed framework outperforms state-of-the-art methods based on the experiments on two different datasets with other baselines.

关键词： data stream classification mobile sensors multi-task multi-view learning incremental learning

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Ligand effect in surface atomic sites of group VI B transition metals on ultrathin Pt nanowires for enhanced oxygen reduction

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Nano Research 2024年第6期17卷 5298-5304页

作者： Yuwei He Yueguang Chen Renjie Wu Zhihe xiao Mengxian Li Chunfeng shi Leyu Wang State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Petroleum Molecular and Process Engineering SINOPEC Research Institute of Petroleum Processing Co.Beijing 100083China

Increasing the utilization efficiency of platinum is critical for advancing proton exchange-membrane fuel cells(PEMFCs).Despite extensive research on catalysts for the cathodic oxygen reduction reaction(ORR),developing highly active and durable Pt-based catalysts that can suppress surface dealloying in corrosive acid conditions remains challenging.Herein,we report a facile synthesis of bimetallic ultrathin PtM(M=Mo,W,and Cr)nanowires(NWs)composed of group VI B transition metal atomic sites anchored on the surface.These NWs possess uniform sizes and well-controlled atomic arrangements.Compared to PtW and PtCr catalysts,the PtMo0.05 NWs exhibit the highest half-wave potential of 0.935 V and a mass activity of 1.43 A·mgPt^(−1).Remarkably,they demonstrate a remarkable 23.8-fold enhancement in mass activity compared to commercial Pt/C for ORR,surpassing previously reported Pt-based catalysts.Additionally,the PtMo NWs cathode in membrane electrode assembly tests achieves a remarkable peak power density of 1.443 W·cm^(−2)(H_(2)-O_(2)conditions at 80℃),which is 1.09 times that of commercial Pt/C.The ligand effect in the bimetallic surface not only facilitates strong coupling between Mo(4d)and Pt(5d)atomic orbitals to hinder atom leaching but also modulates the d-states of active site,significantly optimizing the adsorption of key oxygen(*O and*OH)species and accelerating the rate-determining step in ORR pathways.

关键词： ligand effect oxygen reduction reaction group VI B transition metal ultrathin nanowires multiple oxygen species

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OH regulator of highly dispersed Ru sites on host Pd nanocrystals for selective ethanol electro-oxidation

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Nano Research 2024年第5期17卷 3863-3871页

作者： Zhihe xiao Yueguang Chen Renjie Wu Yuwei He Chunfeng shi Leyu Wang State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Research Institute of Petroleum Processing SINOPECBeijing 100083China

The ethanol oxidation reaction(EOR)is crucial in direct alcohol fuel cells and chemical production.However,the electro-oxidation of ethanol molecules to produce acetaldehyde and carbon monoxide can poison the active sites of nanocatalysts,resulting in reduced performance and posing challenges in achieving high activity and selectivity for ethanol oxidation.In this study,we employed a dynamic seed-mediated method to precisely modify highly dispersed Ru sites onto well-defined Pd nanocrystals.The oxyphilic Ru sites serve as"OH valves",regulating water dissociation,while the surrounding Pd atomic arrangements control electronic states for the oxidation dehydrogenation of carbonaceous intermediates.Specifically,Ru0.040@Pd nanocubes(Ru:Pd=0.04 at.%),featuring(100)facets in Ru-Pd4 configurations,demonstrate an outstanding mass activity of 6.53 A·mgPd^(-1) in EOR under alkaline conditions,which is 6.05 times higher than that of the commercial Pd/C catalyst(1.08 A·mgPd-1).Through in-situ experiments and theoretical investigations,we elucidate that the hydrophilic Ru atoms significantly promote the dynamic evolution of H_(2)O dissociation into OHads species,while the electron redistribution from Ru to adjacent Pd concurrently adjusts the selective oxidation of C_(2) intermediates.This host-guest interaction accelerates the subsequent oxidation of carbonaceous intermediates(CH_(3)CO_(ads))to acetate,while preventing the formation of toxic*CHx and*CO species,which constitutes the rate-determining step.

关键词： OH regulator atomic sites ethanol electro-oxidation host-guest interaction

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Associations between remnant cholesterol levels and mortality in patients with diabetes

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World Journal of Diabetes 2024年第4期15卷 712-723页

作者： Deng Pan Lin Xu Li-xiao Zhang Da-Zhuo shi Ming Guo Department of Cardiovascular Xiyuan Hospital of China Academy of Chinese Medical SciencesBeijing 100091China Graduate School Beijing University of Chinese MedicineBeijing 100020China National Clinical Research Center for Chinese Medicine Cardiology Xiyuan Hospital of China Academy of Chinese Medical SciencesBeijing 100091China Gynecological Department of Traditional Chinese Medicine China-Japan Friendship HospitalBeijing 100020China

BACKGROUND Dyslipidemia is frequently present in patients with diabetes.The associations of remnant cholesterol and mortality remains unclear in patients with diabetes.AIM To explore the associations of remnant cholesterol with all-cause and cardiovas-cular mortality in patients with diabetes.METHODS This prospective cohort study included 4740 patients with diabetes who par-ticipated in the National Health and Nutrition Examination Survey from 1999 through 2018.Remnant cholesterol was used as the exposure variable,and all-cause and cardiovascular mortality were considered outcome events.Outcome data were obtained from the National Death Index,and all participants were followed from the interview date until death or December 31,2019.Multivariate proportional Cox regression models were used to explore the associations between exposure and outcomes,in which remnant cholesterol was modeled as both a categorical and a continuous variable.Restricted cubic splines(RCSs)were calculated to assess the nonlinearity of associations.Subgroup(stratified by sex,age,body mass index,and duration of diabetes)and a series of sensitivity analyses were performed to evaluate the robustness of the associations.RESULTS During a median follow-up duration of 83 months,1370 all-cause deaths and 389 cardiovascular deaths were documented.Patients with remnant cholesterol levels in the third quartile had a reduced risk of all-cause mortality[hazard ratio(HR)95%confidence interval(CI):0.66(0.52-0.85)];however,when remnant cholesterol was modeled as a continuous variable,it was associated with increased risks of all-cause[HR(95%CI):1.12(1.02-1.21)per SD]and cardiovascular[HR(95%CI):1.16(1.01-1.32),per SD]mortality.The RCS demonstrated nonlinear associations of remnant cholesterol with all-cause and cardiovascular mortality.Subgroup and sensitivity analyses did not reveal significant differences from the above results.CONCLUSION In patients with diabetes,higher remnant cholesterol was associated with increased risks of all-cause and cardiovascul

关键词： Diabetes Remnant cholesterol Mortality Cardiovascular National Health and Nutrition Examination Survey

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A pH/ROS dual-responsive system for effective chemoimmunotherapy against melanoma via remodeling tumor immune microenvironment

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2263-2280页

作者： Leilei Wang Shanshan He Rong Liu Yuan Xue Yuan quan Rongying shi Xueying Yang Qing Lin Xun Sun Zhirong Zhang Ling Zhang Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry West China School of PharmacySichuan UniversityChengdu 610041China Med-X Center for Materials College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China

Chemotherapeutics can induce immunogenic cell death(ICD)in tumor cells,offering new possibilities for cancer therapy.However,the efficiency of the immune response generated is insufficient due to the inhibitory nature of the tumor microenvironment(TME).Here,we developed a pH/reactive oxygen species(ROS)dual-response system to enhance chemoimmunotherapy for melanoma.The system productively accumulated in tumors by specific binding of phenylboronic acid(PBA)to sialic acids(SA).The nanoparticles(NPs)rapidly swelled and released quercetin(QUE)and doxorubicin(DOX)upon the stimulation of tumor microenvironment(TME).The in vitro and in vivo results consistently demonstrated that the NPs improved anti-tumor efficacy and prolonged survival of mice,significantly enhancing the effects of the combination.Our study revealed DOX was an ICD inducer,stimulating immune responses and promoting maturation of dendritic cells(DCs).Additionally,QUE served as a TME regulator by inhibiting the cyclooxygenase-2(COX2)-prostaglandin E2(PGE2)axis,which influenced various immune cells,including increasing cytotoxic T cells(CLTs)infiltration,promoting M1 macrophage polarization,and reducing regulatory T cells(Tregs)infiltration.The combination synergistically facilitated chemoimmunotherapy efficacy by remodeling the immunosuppressive microenvironment.This work presents a promising strategy to increase anti-tumor efficiency of chemotherapeutic agents.

关键词： Quercetin Nanoparticle Responsiveness Chemoimmunotherapy Tumor immune microenvironment

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Comprehensive analysis and mitigation strategies for safety issues of sodium-ion batteries

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Rare Metals 2024年第4期43卷 1343-1349页

作者： Tao Wei xiao-Ling Xian shi-Xue Dou Wei Chen Shu-Lei Chou Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou University Wenzhou Key Laboratory of Sodium-Ion Batteries Wenzhou University Technology Innovation Institute for Carbon Neutralization Zhejiang Key Laboratory of Carbon Materials College of Chemistry and Materials EngineeringWenzhou University Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongInnovation Campus

Sodium-ion batteries show great potential as an alternative energy storage system,but safety concerns remain a major hurdle to their mass adoption.This paper analyzes the key factors and mechanisms leading to safety issues,including thermal runaway,sodium dendrite,internal short circuits,and gas release.Several promising solutions are proposed,such as high-safety electrode materials in the cathode and anode,high-safety electrolytes,and external battery management systems.Here in also we emphasize the importance of selecting appropriate analysis methods and developing reliable failure models while suggesting advanced machine learning tools for analysis.With a comprehensive approach,this study offers valuable recommendations to optimize materials and solutions for improving the safety of sodium-ion batteries.

关键词： Sodium-ion batteries Safety issues Thermal runaway Sodium dendrites

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Poor oral health was associated with higher risk of gastric cancer: Evidence from 1431677 participants

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 585-595页

作者： Fei Liu shi-Jun Tang Zi-Wei Li Xu-Rui Liu quan Lv Wei Zhang Dong Peng Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Pediatric Dentistry Stomatological Hospital of Guizhou Medical UniversityGuizhou 550000Guizhou ProvinceChina

BACKGROUND In recent years,the association between oral health and the risk of gastric cancer(GC)has gradually attracted increased interest.However,in terms of GC incidence,the association between oral health and GC incidence remains contro-versial.Periodontitis is reported to increase the risk of GC.However,some studies have shown that periodontitis has no effect on the risk of GC.Therefore,the present study aimed to assess whether there is a relationship between oral health and the risk of GC.AIM To assess whether there was a relationship between oral health and the risk of GC.METHODS Five databases were searched to find eligible studies from inception to April 10,2023.Newcastle-Ottawa Scale score was used to assess the quality of included studies.The quality of cohort studies and case-control studies were evaluated separately in this study.Incidence of GC were described by odds ratio(OR)and 95%confidence interval(CI).Funnel plot was used to represent the publication bias of included studies.We performed the data analysis by StataSE 16.RESULTS A total of 1431677 patients from twelve included studies were enrolled for data analysis in this study.According to our analysis,we found that the poor oral health was associated with higher risk of GC(OR=1.15,95%CI:1.02-1.29;I2=59.47%,P=0.000.01),gingivitis(OR=1.19,95%CI:0.71-1.67;I2=0.00%,P>0.01),dentures(OR=1.27,95%CI:0.63-1.19;I2=68.79%,P>0.01),or tooth brushing(OR=1.25,95%CI:0.78-1.71;I2=88.87%,P>0.01)had no influence on the risk of GC.However,patients with periodontitis(OR=1.13,95%CI:1.04-1.23;I2=0.00%,P<0.01)had a higher risk of GC.CONCLUSION Patients with poor oral health,especially periodontitis,had a higher risk of GC.Patients should be concerned about their oral health.Improving oral health might reduce the risk of GC.

关键词： Oral health Tooth loss Periodontitis Gastric cancer Risk factor

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