Metal additive manufacturing(MAM)is an emerging and disruptive technology that builds three-dimensional(3D)components by adding layer-upon-layer of metallic materials.The complex cyclic thermal history and highly loca...Metal additive manufacturing(MAM)is an emerging and disruptive technology that builds three-dimensional(3D)components by adding layer-upon-layer of metallic materials.The complex cyclic thermal history and highly localized energy can produce large temperature gradients,which will,in turn,lead to compressive and tensile stress during the MAM process and eventually result in residual stress.Being an issue of great concern,residual stress,which can cause distortion,delamination,cracking,etc.,is considered a key mechanical quantity that affects the manufacturing quality and service performance of MAM parts.In this review paper,the ongoing work in the field of residual stress determination and control for MAM is described with a particular emphasis on the experimental measurement/control methods and numerical models.We also provide insight on what still requires to be achieved and the research opportunities and challenges.展开更多
BACKGROUND Previous studies have suggested that long non-coding RNAs(lncRNA)TP73-AS1 is significantly upregulated in several cancers.However,the biological role and clinical significance of TP73-AS1 in pancreatic canc...BACKGROUND Previous studies have suggested that long non-coding RNAs(lncRNA)TP73-AS1 is significantly upregulated in several cancers.However,the biological role and clinical significance of TP73-AS1 in pancreatic cancer(PC)remain unclear.AIM To investigate the role of TP73-AS1 in the growth and metastasis of PC.METHODS The expression of lncRNA TP73-AS1,miR-128-3p,and GOLM1 in PC tissues and cells was detected by quantitative real-time polymerase chain reaction.The bioinformatics prediction software ENCORI was used to predict the putative binding sites of miR-128-3p.The regulatory roles of TP73-AS1 and miR-128-3p in cell proliferation,migration,and invasion abilities were verified by Cell Counting Kit-8,wound-healing,and transwell assays,as well as flow cytometry and Western blot analysis.The interactions among TP73-AS1,miR-128-3p,and GOLM1 were explored by bioinformatics prediction,luciferase assay,and Western blot.RESULTS The expression of TP73-AS1 and miRNA-128-3p was dysregulated in PC tissues and cells.High TP73-AS1 expression was correlated with a poor prognosis.TP73-AS1 silencing inhibited PC cell proliferation,migration,and invasion in vitro as well as suppressed tumor growth in vivo.Mechanistically,TP73-AS1 was validated to promote PC progression through GOLM1 upregulation by competitively binding to miR-128-3p.CONCLUSION Our results demonstrated that TP73-AS1 promotes PC progression by regulating the miR-128-3p/GOLM1 axis,which might provide a potential treatment strategy for patients with PC.展开更多
The appearance of pedestrians can vary greatly from image to image,and different pedestrians may look similar in a given image.Such similarities and variabilities in the appearance and clothing of individuals make the...The appearance of pedestrians can vary greatly from image to image,and different pedestrians may look similar in a given image.Such similarities and variabilities in the appearance and clothing of individuals make the task of pedestrian re-identification very challenging.Here,a pedestrian re-identification method based on the fusion of local features and gait energy image(GEI)features is proposed.In this method,the human body is divided into four regions according to joint points.The color and texture of each region of the human body are extracted as local features,and GEI features of the pedestrian gait are also obtained.These features are then fused with the local and GEI features of the person.Independent distance measure learning using the cross-view quadratic discriminant analysis(XQDA)method is used to obtain the similarity of the metric function of the image pairs,and the final similarity is acquired by weight matching.Evaluation of experimental results by cumulative matching characteristic(CMC)curves reveals that,after fusion of local and GEI features,the pedestrian re-identification effect is improved compared with existing methods and is notably better than the recognition rate of pedestrian re-identification with a single feature.展开更多
Increasing the utilization efficiency of photogenerated electrons is highly recognized as one of the ef-ficient approaches to boost the photocatalytic CO_(−2)conversion efficiency.Herein,ZIF-67-derived porous carbon(P...Increasing the utilization efficiency of photogenerated electrons is highly recognized as one of the ef-ficient approaches to boost the photocatalytic CO_(−2)conversion efficiency.Herein,ZIF-67-derived porous carbon(PC)material was employed for the construction of PC@ultrafine Bi_(12)O_(17)Br_(2)nanotubes(PC@BOB NTs)composites through a facile solvothermal synthesis in order to optimize the use of excited elec-trons in the BOB NTs.Photoelectrochemical characterization results revealed that the introduction of PC material achieved a faster charge separation rate in the PC@BOB composites,ensuring more photogener-ated electrons participate in the CO_(−2)adsorption and activation process.Moreover,the pore structures of ZIF-67-derived PC material provided abundant confined spaces for the enrichment of CO_(−2)molecules.Af-ter 5 h of Xenon lamp irradiation,PC@BOB composites exhibited obviously increased photocatalytic CO_(−2)reduction activity in the pure water.When the addition amount of PC was 5 wt%,the PC@BOB-2 com-posite showed the highest CO evolution rate of 359.70μmol/g,which was 2.95 times higher than that of the pure BOB NTs.This work provides some independent insights into the applications of Metal-Organic Framework(MOF)-derived hierarchical porous structures to strengthen the CO_(−2)enrichment,as well as the excited charge utilization efficiency,thus achieving a high solar-to-fuel conversion efficiency.展开更多
The direct bonding copper(DBC)substrates of insulated gate bipolar transistor(IGBT)modules degrade inevitably under cycling thermo‐mechanical stress,causing potential threat to the reliability of IGBT modules.However...The direct bonding copper(DBC)substrates of insulated gate bipolar transistor(IGBT)modules degrade inevitably under cycling thermo‐mechanical stress,causing potential threat to the reliability of IGBT modules.However,little attention has been paid to monitoring their degradation.This paper proposes a DBC degradation monitoring method for IGBT modules,which combines boundary‐dependent thermal network and feedback control.A thermal network is employed to describe the internal material degradation of IGBT modules and can be extracted from a finite‐element method model.The boundary conditions including power losses and DBC degradation are considered,enabling the thermal network suitable for various working conditions and different DBC degradation conditions of IGBT modules.The DBC degradation is characterised by its equivalent thermal conductivities measured in the thermal cycling ageing experiments.On the basis of the boundary‐dependent thermal network,feedback control is applied to monitor DBC degradation by regulating boundary‐dependent thermal impedances.Finally,the proposed model is verified from the effectiveness and accuracy of DBC degradation monitoring and junction temperature calculation.This method casts new light on thermal network modelling and could provide a feasible method for the monitoring of DBC degradation.展开更多
Background:There is limited information about thymosinα1(Tα1)as adjuvant immunomodulatory therapy,either used alone or combined with other treatments,in patients with non-small cell lung cancer(NSCLC).This study aim...Background:There is limited information about thymosinα1(Tα1)as adjuvant immunomodulatory therapy,either used alone or combined with other treatments,in patients with non-small cell lung cancer(NSCLC).This study aimed to evaluate the effect of adjuvant Tα1 treatment on long-term survival in margin-free(R0)-resected stage IA–IIIA NSCLC patients.Methods:A total of 5746 patients with pathologic stage IA-IIIA NSCLC who underwent R0 resection were included.The patients were divided into the Tα1 group and the control group according to whether they received Tα1 or not.A propensity score matching(PSM)analysis was performed to reduce bias,resulting in 1027 pairs of patients.Results:After PSM,the baseline clinicopathological characteristics were similar between the two groups.The 5-year disease-free survival(DFS)and overall survival(OS)rates were significantly higher in the Tα1 group compared with the control group.The multivariable analysis showed that Tα1 treatment was independently associated with an improved prognosis.A longer duration of Tα1 treatment was associated with improved OS and DFS.The subgroup analyses showed that Tα1 therapy could improve the DFS and/or OS in all subgroups of age,sex,Charlson Comorbidity Index(CCI),smoking status,and pathological tumor-node-metastasis(TNM)stage,especially for patients with non-squamous cell NSCLC and without targeted therapy.Conclusion:Tα1 as adjuvant immunomodulatory therapy can significantly improve DFS and OS in patients with NSCLC after R0 resection,except for patients with squamous cell carcinoma and those receiving targeted therapy.The duration of Tα1 treatment is recommended to be>24 months.展开更多
Chemical vapor deposition(CVD)is one of the most versatile techniques for the controlled synthesis of functional nanomaterials.When multiple precursors are induced,the CVD process often gives rise to the growth of dop...Chemical vapor deposition(CVD)is one of the most versatile techniques for the controlled synthesis of functional nanomaterials.When multiple precursors are induced,the CVD process often gives rise to the growth of doped or alloy compounds.In this work,we demonstrate the self-assembly of a variety of‘phase-separated’functional nanostructures from a single CVD in the presence of various precursors.In specific,with silicon substrate and powder of Mn and SnTe as precursors,we achieved self-organized nanostructures including Si/SiOx core-shell nanowire heterostructures both with and without embedded manganese silicide particles,Mn11Si19 nanowires,and SnTe nanoplates.The Si/SiOx core-shell nanowires embedded with manganese silicide particles were grown along the<111>direction of the crystalline Si via an Au-catalyzed vapor-liquid-solid process,in which the Si and Mn vapors were supplied from the heated silicon substrates and Mn powder,respectively.In contrast,direct vapor-solid deposition led to particle-free<110>-oriented Si/SiOx core-shell nanowires and<100>-oriented Mn11Si19 nanowires,a promising thermoelectric material.No Sn or Te impurities were detected in these nanostructures down to the experimental limit.Topological crystalline insulator SnTe nanoplates with dominant{100}and{111}facets were found to be free of Mn(and Si)impurities,although nanoparticles and nanowires containing Mn were found in the vicinity of the nanoplates.While multiple-channel transport was observed in the SnTe nanoplates,it may not be related to the topological surface states due to surface oxidation.Finally,we carried out thermodynamic analysis and density functional theory calculations to understand the‘phase-separation’phenomenon and further discuss general approaches to grow phase-pure samples when the precursors contain residual impurities.展开更多
基金financially supported by the National Natural Science Foundation of China(12032013,12272131)the Provincial Natural Science Foundation of Hunan(2022JJ40029)the Scientific Research Foundation of Hunan Provincial Education Department(21C0087)。
文摘Metal additive manufacturing(MAM)is an emerging and disruptive technology that builds three-dimensional(3D)components by adding layer-upon-layer of metallic materials.The complex cyclic thermal history and highly localized energy can produce large temperature gradients,which will,in turn,lead to compressive and tensile stress during the MAM process and eventually result in residual stress.Being an issue of great concern,residual stress,which can cause distortion,delamination,cracking,etc.,is considered a key mechanical quantity that affects the manufacturing quality and service performance of MAM parts.In this review paper,the ongoing work in the field of residual stress determination and control for MAM is described with a particular emphasis on the experimental measurement/control methods and numerical models.We also provide insight on what still requires to be achieved and the research opportunities and challenges.
基金National Natural Science Foundation of China,No.81974372.
文摘BACKGROUND Previous studies have suggested that long non-coding RNAs(lncRNA)TP73-AS1 is significantly upregulated in several cancers.However,the biological role and clinical significance of TP73-AS1 in pancreatic cancer(PC)remain unclear.AIM To investigate the role of TP73-AS1 in the growth and metastasis of PC.METHODS The expression of lncRNA TP73-AS1,miR-128-3p,and GOLM1 in PC tissues and cells was detected by quantitative real-time polymerase chain reaction.The bioinformatics prediction software ENCORI was used to predict the putative binding sites of miR-128-3p.The regulatory roles of TP73-AS1 and miR-128-3p in cell proliferation,migration,and invasion abilities were verified by Cell Counting Kit-8,wound-healing,and transwell assays,as well as flow cytometry and Western blot analysis.The interactions among TP73-AS1,miR-128-3p,and GOLM1 were explored by bioinformatics prediction,luciferase assay,and Western blot.RESULTS The expression of TP73-AS1 and miRNA-128-3p was dysregulated in PC tissues and cells.High TP73-AS1 expression was correlated with a poor prognosis.TP73-AS1 silencing inhibited PC cell proliferation,migration,and invasion in vitro as well as suppressed tumor growth in vivo.Mechanistically,TP73-AS1 was validated to promote PC progression through GOLM1 upregulation by competitively binding to miR-128-3p.CONCLUSION Our results demonstrated that TP73-AS1 promotes PC progression by regulating the miR-128-3p/GOLM1 axis,which might provide a potential treatment strategy for patients with PC.
基金This research was funded by the Science and Technology Support Plan Project of Hebei Province(grant numbers 17210803D and 19273703D)the Science and Technology Spark Project of the Hebei Seismological Bureau(grant number DZ20180402056)+1 种基金the Education Department of Hebei Province(grant number QN2018095)the Polytechnic College of Hebei University of Science and Technology.
文摘The appearance of pedestrians can vary greatly from image to image,and different pedestrians may look similar in a given image.Such similarities and variabilities in the appearance and clothing of individuals make the task of pedestrian re-identification very challenging.Here,a pedestrian re-identification method based on the fusion of local features and gait energy image(GEI)features is proposed.In this method,the human body is divided into four regions according to joint points.The color and texture of each region of the human body are extracted as local features,and GEI features of the pedestrian gait are also obtained.These features are then fused with the local and GEI features of the person.Independent distance measure learning using the cross-view quadratic discriminant analysis(XQDA)method is used to obtain the similarity of the metric function of the image pairs,and the final similarity is acquired by weight matching.Evaluation of experimental results by cumulative matching characteristic(CMC)curves reveals that,after fusion of local and GEI features,the pedestrian re-identification effect is improved compared with existing methods and is notably better than the recognition rate of pedestrian re-identification with a single feature.
基金supported by the National Natural Science Foundation of China(Nos.22108108,22108106,22109055)China Postdoctoral Science Foundation(No.2022M721381).
文摘Increasing the utilization efficiency of photogenerated electrons is highly recognized as one of the ef-ficient approaches to boost the photocatalytic CO_(−2)conversion efficiency.Herein,ZIF-67-derived porous carbon(PC)material was employed for the construction of PC@ultrafine Bi_(12)O_(17)Br_(2)nanotubes(PC@BOB NTs)composites through a facile solvothermal synthesis in order to optimize the use of excited elec-trons in the BOB NTs.Photoelectrochemical characterization results revealed that the introduction of PC material achieved a faster charge separation rate in the PC@BOB composites,ensuring more photogener-ated electrons participate in the CO_(−2)adsorption and activation process.Moreover,the pore structures of ZIF-67-derived PC material provided abundant confined spaces for the enrichment of CO_(−2)molecules.Af-ter 5 h of Xenon lamp irradiation,PC@BOB composites exhibited obviously increased photocatalytic CO_(−2)reduction activity in the pure water.When the addition amount of PC was 5 wt%,the PC@BOB-2 com-posite showed the highest CO evolution rate of 359.70μmol/g,which was 2.95 times higher than that of the pure BOB NTs.This work provides some independent insights into the applications of Metal-Organic Framework(MOF)-derived hierarchical porous structures to strengthen the CO_(−2)enrichment,as well as the excited charge utilization efficiency,thus achieving a high solar-to-fuel conversion efficiency.
基金supported by the National Key Research and Development Program of China(No.2018YFB0905802).
文摘The direct bonding copper(DBC)substrates of insulated gate bipolar transistor(IGBT)modules degrade inevitably under cycling thermo‐mechanical stress,causing potential threat to the reliability of IGBT modules.However,little attention has been paid to monitoring their degradation.This paper proposes a DBC degradation monitoring method for IGBT modules,which combines boundary‐dependent thermal network and feedback control.A thermal network is employed to describe the internal material degradation of IGBT modules and can be extracted from a finite‐element method model.The boundary conditions including power losses and DBC degradation are considered,enabling the thermal network suitable for various working conditions and different DBC degradation conditions of IGBT modules.The DBC degradation is characterised by its equivalent thermal conductivities measured in the thermal cycling ageing experiments.On the basis of the boundary‐dependent thermal network,feedback control is applied to monitor DBC degradation by regulating boundary‐dependent thermal impedances.Finally,the proposed model is verified from the effectiveness and accuracy of DBC degradation monitoring and junction temperature calculation.This method casts new light on thermal network modelling and could provide a feasible method for the monitoring of DBC degradation.
基金Acknowledgements This work was partially supported by the National Natural Science Foundation of China （Grant No. 41271208）, the JiangsuPlanned Projects for Postdoctoral Research Funds （No. 1301061C）, the China Postdoctoral Science Foundation funded project （No. 2013M541744）, and the Key Projects in the National Science ＆ Technology Pillar Program during the Twelfth Five-year Plan Period （2013BADllB00）. We also express our sincere thanks to Ms. Yanan Zhang and Ms. Yilan Liu for their kind help with the sampling.
基金1.3.5 project for disciplines of excellence,West China Hospital,Sichuan University(Nos.ZYGD18021 and ZYJC18009).
文摘Background:There is limited information about thymosinα1(Tα1)as adjuvant immunomodulatory therapy,either used alone or combined with other treatments,in patients with non-small cell lung cancer(NSCLC).This study aimed to evaluate the effect of adjuvant Tα1 treatment on long-term survival in margin-free(R0)-resected stage IA–IIIA NSCLC patients.Methods:A total of 5746 patients with pathologic stage IA-IIIA NSCLC who underwent R0 resection were included.The patients were divided into the Tα1 group and the control group according to whether they received Tα1 or not.A propensity score matching(PSM)analysis was performed to reduce bias,resulting in 1027 pairs of patients.Results:After PSM,the baseline clinicopathological characteristics were similar between the two groups.The 5-year disease-free survival(DFS)and overall survival(OS)rates were significantly higher in the Tα1 group compared with the control group.The multivariable analysis showed that Tα1 treatment was independently associated with an improved prognosis.A longer duration of Tα1 treatment was associated with improved OS and DFS.The subgroup analyses showed that Tα1 therapy could improve the DFS and/or OS in all subgroups of age,sex,Charlson Comorbidity Index(CCI),smoking status,and pathological tumor-node-metastasis(TNM)stage,especially for patients with non-squamous cell NSCLC and without targeted therapy.Conclusion:Tα1 as adjuvant immunomodulatory therapy can significantly improve DFS and OS in patients with NSCLC after R0 resection,except for patients with squamous cell carcinoma and those receiving targeted therapy.The duration of Tα1 treatment is recommended to be>24 months.
基金This work was supported,in part,by the Indiana University Vice Provost for Research through the Faculty Research Support Program,National Science Foundation Research Experience for Undergraduates grant PHY-1757646,NSF-DMR-1350002We thank the Indiana University-Bloomington Nanoscale Characterization Facility(NCF)for the use of instruments(The XPS instrument at NCF was funded through grant NSF-DMR-1126394).
文摘Chemical vapor deposition(CVD)is one of the most versatile techniques for the controlled synthesis of functional nanomaterials.When multiple precursors are induced,the CVD process often gives rise to the growth of doped or alloy compounds.In this work,we demonstrate the self-assembly of a variety of‘phase-separated’functional nanostructures from a single CVD in the presence of various precursors.In specific,with silicon substrate and powder of Mn and SnTe as precursors,we achieved self-organized nanostructures including Si/SiOx core-shell nanowire heterostructures both with and without embedded manganese silicide particles,Mn11Si19 nanowires,and SnTe nanoplates.The Si/SiOx core-shell nanowires embedded with manganese silicide particles were grown along the<111>direction of the crystalline Si via an Au-catalyzed vapor-liquid-solid process,in which the Si and Mn vapors were supplied from the heated silicon substrates and Mn powder,respectively.In contrast,direct vapor-solid deposition led to particle-free<110>-oriented Si/SiOx core-shell nanowires and<100>-oriented Mn11Si19 nanowires,a promising thermoelectric material.No Sn or Te impurities were detected in these nanostructures down to the experimental limit.Topological crystalline insulator SnTe nanoplates with dominant{100}and{111}facets were found to be free of Mn(and Si)impurities,although nanoparticles and nanowires containing Mn were found in the vicinity of the nanoplates.While multiple-channel transport was observed in the SnTe nanoplates,it may not be related to the topological surface states due to surface oxidation.Finally,we carried out thermodynamic analysis and density functional theory calculations to understand the‘phase-separation’phenomenon and further discuss general approaches to grow phase-pure samples when the precursors contain residual impurities.
