The silver-palladium(Ag-Pd) alloy coating as a solid lubricant was investigated for its application to the high temperature stud bolts used in nuclear power plants.A hex bolt sample was prepared in the following steps...The silver-palladium(Ag-Pd) alloy coating as a solid lubricant was investigated for its application to the high temperature stud bolts used in nuclear power plants.A hex bolt sample was prepared in the following steps:1) bolt surface treatment using alumina grit blasting for cleaning and increasing the surface area;2) nickel(Ni) film coating as a glue layer on the surface of the bolt;and 3) Ag-Pd alloy coating on the Ni film.The films were deposited by using a direct current(DC) magnetron sputtering system.The thickness and composition of the Ag-Pd alloy film have effect on the friction coefficient,which was determined using axial force measurement.A 500 nm-thick Ag-Pd(80-20,molar ratio) alloy film has the lowest friction coefficient of 0.109.A cyclic test was conducted to evaluate the durability of bolts coated with either the Ag-Pd(80-20) alloy film or N-5000 oil.In a cycle,the bolts were inserted into a block using a torque wrench,which was followed by heating and disassembling.After only one cycle,it was not possible to remove the bolts coated with the N-5000 oil from the block.However,the bolts coated with the Ag-Pd(80-20) alloy could be easily removed up until 15 cycles.展开更多
Leiomyosarcoma of an artery is very rare, and cases with hepatic metastasis are even rarer. We describe a case of a 70-year-old man who after follow up due to rectal cancer, presented with an intra-abdominal hypervasc...Leiomyosarcoma of an artery is very rare, and cases with hepatic metastasis are even rarer. We describe a case of a 70-year-old man who after follow up due to rectal cancer, presented with an intra-abdominal hypervascular mass and a hepatic mass. After surgical resection, it was diagnosed as a leiomyosarcoma of the right gastroepiploic artery with hepatic metastasis. Multiple metastases had recurred at the liver. He has survived more than 53 mo through multimodal treatments(three surgical resections, radiofrequency ablation, transarterial chemoembolization, chemotherapies, and targeted therapy). Multimodal treatments, including active surgical resection, may behelpful in the treatment of aggressive diseases such as arterial leiomyosarcoma with metastasis.展开更多
Glucagon peptide-like 1(GLP-1)and GLP-1 receptor(GLP-1R):GLP-1 is an incretin hormone secreted from gut L cells.GLP-1 exerts its action through binding to its specific receptor,GLP-1R,which is a member of the G p...Glucagon peptide-like 1(GLP-1)and GLP-1 receptor(GLP-1R):GLP-1 is an incretin hormone secreted from gut L cells.GLP-1 exerts its action through binding to its specific receptor,GLP-1R,which is a member of the G protein-coupled receptor superfamily.GLP-1R is reportedly expressed in various organs,such as the liver,kidney,and peripheral tissues.展开更多
BACKGROUND Metaplastic breast cancer(MBC)is a rare subtype of breast cancer.They constitute less than 1%of breast cancer cases and are much rarer in males.There are few reports of MBC because of its rarity.MBC,an aggr...BACKGROUND Metaplastic breast cancer(MBC)is a rare subtype of breast cancer.They constitute less than 1%of breast cancer cases and are much rarer in males.There are few reports of MBC because of its rarity.MBC,an aggressive type of cancer,is refractory to common treatment modalities of breast cancer and has a poor prognosis.CASE SUMMARY We report a case of MBC in a 78-year-old man.He visited our clinic with a palpable mass on the left breast with no masses in the axillary areas.He had previously undergone robot-assisted laparoscopic radical prostatectomy for prostate cancer,but there was no family history of malignancy.The breast mass was visible on ultrasonography,mammography,and magnetic resonance imaging,and chest computed tomography revealed a lung mass in the posterior basal segment of the right lower lobe.The patient was diagnosed with metaplastic carcinoma on core needle biopsy with lung metastasis.Total mastectomy with sentinel lymph node biopsy and video-assisted segmentectomy of the right lung was performed.However,multiple metastases appeared 3 mo after surgery in the brain,chest,and abdomen,and the patient died 5 mo after the initial diagnosis.CONCLUSION MBC is an aggressive and extremely rare breast cancer type.Further case reports are needed to determine the optimal treatment.展开更多
This work demonstrated the viability of friction stir welding for the welding of medium-Mn steels when used as cryogenic vessel materials for liquefied gas storage.We used an intercritically annealed Fe-7 Mn-0.2 C-3 A...This work demonstrated the viability of friction stir welding for the welding of medium-Mn steels when used as cryogenic vessel materials for liquefied gas storage.We used an intercritically annealed Fe-7 Mn-0.2 C-3 Al(wt.%)steel with a dual-phase(α'martensite andγ_(R) retained austenite)nanolaminate structure as a base material and systematically compared its microstructure and impact toughness after friction stir and tungsten inert gas welding.The friction stir welded specimen exhibited a large amount ofγ_(R) phase owing to a relatively low temperature during welding,whereas the tungsten inert gas welded specimen comprised only theα'phase.Furthermore,the friction stir welded steel exhibited a tuned morphology of nanoscale globular microstructure at the weld zone and did not exhibit any prior austenite grain boundary due to active recrystallization caused by deformation during welding.The preserved fraction ofγ_(R) and morphological tuning in the weldment improved the impact toughness of the friction stir welded steel at low temperatures.In the steel processed by tungsten inert gas welding,the notch crack propagated rapidly along the prior austenite grain boundaries-weakened by Mn and P segregations-resulting in poor impact toughness.However,the friction stir welded steel exhibited a higher resistance against notch crack propagation due to the slow crack propagation along the ultrafine ferrite/ferrite(α/α)interfaces,damage tolerance by the active transformation-induced plasticity from the large amount ofγR,and enhanced boundary cohesion by suppressed Mn and P segregations.展开更多
基金Project supported by Power Research and Development Program funded by Ministry of Knowledge Economy and Korea Institute of Materials Science,a subsidiary branch of Korea Institute of Machinery and Materials
文摘The silver-palladium(Ag-Pd) alloy coating as a solid lubricant was investigated for its application to the high temperature stud bolts used in nuclear power plants.A hex bolt sample was prepared in the following steps:1) bolt surface treatment using alumina grit blasting for cleaning and increasing the surface area;2) nickel(Ni) film coating as a glue layer on the surface of the bolt;and 3) Ag-Pd alloy coating on the Ni film.The films were deposited by using a direct current(DC) magnetron sputtering system.The thickness and composition of the Ag-Pd alloy film have effect on the friction coefficient,which was determined using axial force measurement.A 500 nm-thick Ag-Pd(80-20,molar ratio) alloy film has the lowest friction coefficient of 0.109.A cyclic test was conducted to evaluate the durability of bolts coated with either the Ag-Pd(80-20) alloy film or N-5000 oil.In a cycle,the bolts were inserted into a block using a torque wrench,which was followed by heating and disassembling.After only one cycle,it was not possible to remove the bolts coated with the N-5000 oil from the block.However,the bolts coated with the Ag-Pd(80-20) alloy could be easily removed up until 15 cycles.
文摘Leiomyosarcoma of an artery is very rare, and cases with hepatic metastasis are even rarer. We describe a case of a 70-year-old man who after follow up due to rectal cancer, presented with an intra-abdominal hypervascular mass and a hepatic mass. After surgical resection, it was diagnosed as a leiomyosarcoma of the right gastroepiploic artery with hepatic metastasis. Multiple metastases had recurred at the liver. He has survived more than 53 mo through multimodal treatments(three surgical resections, radiofrequency ablation, transarterial chemoembolization, chemotherapies, and targeted therapy). Multimodal treatments, including active surgical resection, may behelpful in the treatment of aggressive diseases such as arterial leiomyosarcoma with metastasis.
基金supported financially by a research grant from National Research Foundation of Korea(NRF-2010-0023627)
文摘Glucagon peptide-like 1(GLP-1)and GLP-1 receptor(GLP-1R):GLP-1 is an incretin hormone secreted from gut L cells.GLP-1 exerts its action through binding to its specific receptor,GLP-1R,which is a member of the G protein-coupled receptor superfamily.GLP-1R is reportedly expressed in various organs,such as the liver,kidney,and peripheral tissues.
基金Supported by the 2020 research grant from Pusan National University Yangsan Hospital,No.2020-193.
文摘BACKGROUND Metaplastic breast cancer(MBC)is a rare subtype of breast cancer.They constitute less than 1%of breast cancer cases and are much rarer in males.There are few reports of MBC because of its rarity.MBC,an aggressive type of cancer,is refractory to common treatment modalities of breast cancer and has a poor prognosis.CASE SUMMARY We report a case of MBC in a 78-year-old man.He visited our clinic with a palpable mass on the left breast with no masses in the axillary areas.He had previously undergone robot-assisted laparoscopic radical prostatectomy for prostate cancer,but there was no family history of malignancy.The breast mass was visible on ultrasonography,mammography,and magnetic resonance imaging,and chest computed tomography revealed a lung mass in the posterior basal segment of the right lower lobe.The patient was diagnosed with metaplastic carcinoma on core needle biopsy with lung metastasis.Total mastectomy with sentinel lymph node biopsy and video-assisted segmentectomy of the right lung was performed.However,multiple metastases appeared 3 mo after surgery in the brain,chest,and abdomen,and the patient died 5 mo after the initial diagnosis.CONCLUSION MBC is an aggressive and extremely rare breast cancer type.Further case reports are needed to determine the optimal treatment.
基金supported by the National Research Foundation of Korea(NRF)(No.2020R1F1A1070808)supported by the Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(P0008425,The Competency Development Program for Industry Specialist)。
文摘This work demonstrated the viability of friction stir welding for the welding of medium-Mn steels when used as cryogenic vessel materials for liquefied gas storage.We used an intercritically annealed Fe-7 Mn-0.2 C-3 Al(wt.%)steel with a dual-phase(α'martensite andγ_(R) retained austenite)nanolaminate structure as a base material and systematically compared its microstructure and impact toughness after friction stir and tungsten inert gas welding.The friction stir welded specimen exhibited a large amount ofγ_(R) phase owing to a relatively low temperature during welding,whereas the tungsten inert gas welded specimen comprised only theα'phase.Furthermore,the friction stir welded steel exhibited a tuned morphology of nanoscale globular microstructure at the weld zone and did not exhibit any prior austenite grain boundary due to active recrystallization caused by deformation during welding.The preserved fraction ofγ_(R) and morphological tuning in the weldment improved the impact toughness of the friction stir welded steel at low temperatures.In the steel processed by tungsten inert gas welding,the notch crack propagated rapidly along the prior austenite grain boundaries-weakened by Mn and P segregations-resulting in poor impact toughness.However,the friction stir welded steel exhibited a higher resistance against notch crack propagation due to the slow crack propagation along the ultrafine ferrite/ferrite(α/α)interfaces,damage tolerance by the active transformation-induced plasticity from the large amount ofγR,and enhanced boundary cohesion by suppressed Mn and P segregations.