The Chinese Academy of Engineering Physics Terahertz Free Electron Laser Facility(CAEP THz FEL,CTFEL)is the only high-average power free electron laser terahertz source based on superconducting accelerators in China.T...The Chinese Academy of Engineering Physics Terahertz Free Electron Laser Facility(CAEP THz FEL,CTFEL)is the only high-average power free electron laser terahertz source based on superconducting accelerators in China.The update of the CTFEL is now undergoing and will expand the frequency range from 0.1–4.2 THz to 0.1–125 THz.Two experimental stations for material spectroscopy and biomedicine will be built.A high harmonic generation(HHG)lightsource based beamline at the material spectroscopy experimental station for time-resolved angle-resolved photoemission spectroscopy(ARPES)research will be constructed and the optical design is presented.The HHG lightsource covers the extreme ultraviolet(XUV)photon energy range of 20–50 eV.A Czerny–Turner monochromator with two plane gratings worked in conical diffraction configuration is employed to maintain the transmission efficiency and preserve the pulse time duration.The calculated beamline transmission efficiency is better than 5%in the whole photon energy range.To our knowledge,this is the first time in China to combine THz-infrared FEL with HHG light source,and this experimental station will be a powerful and effective instrument that will give new research opportunities in the future for users doing research on the dynamic evolution of the excited electron band structure of a material’s surface.展开更多
BACKGROUND Peutz-Jeghers syndrome(PJS)has brought significant physical,psychological and economic burdens on the patients and their families due to its early onset,diagnostic and therapeutic challenges and increased r...BACKGROUND Peutz-Jeghers syndrome(PJS)has brought significant physical,psychological and economic burdens on the patients and their families due to its early onset,diagnostic and therapeutic challenges and increased recurrence risk.AIM To explore the current research status and emerging hotspots of PJS.METHODS Studies on PJS published during 1994-2023 were gathered based on Web of Science Core Collection.Additionally,a case of PJS-induced intestinal intussusception,successfully treated with endoscopic methods despite three laparotomies,was highlighted.Comprehensive bibliometric and visual analysis were conducted with VOSviewer,R and CiteSpace.RESULTS Altogether 1760 studies were identified,indicating a steady increase in the publication number.The United States had the highest influence,whereas the University of Helsinki emerged as the leading institution,and Aaltonen LA from the University of Helsinki was the most prolific author.Cancer Research,Oncogene and Endoscopy were the top three journals based on H-index.Keyword burst direction analysis revealed that"cancer risk","management","surveillance"and"familial pancreatic cancer"were the potential hotspots for investigation.Additionally,"early detection","capsule endoscopy","clinical management","double-balloon endoscopy","familial pancreatic cancer"and"molecular genetic basis"were identified as the key clusters of co-cited references.Endoscopic polypectomy remained effective on resolving intestinal intussusception in patients who underwent three previous laparotomies.CONCLUSION In the last three decades,global publications related to PJS show a steadily increasing trend in number.Endoscopic management is currently a research hotspot.展开更多
3Y-TZP/3wt%Al_(2)O_(3) powder was coated with varying amounts of BN using the urea and borate reaction sintering method,and then multiphase ceramics were prepared by hot pressing sintering.The micro-topography and the...3Y-TZP/3wt%Al_(2)O_(3) powder was coated with varying amounts of BN using the urea and borate reaction sintering method,and then multiphase ceramics were prepared by hot pressing sintering.The micro-topography and the compositional analysis of synthesized ceramics were conducted through scanning electron microscopy,transmission electron microscopy and X-ray diffraction.A mechanical tester was used to analyze the Vickers hardness,fracture toughness,and bending strength of the synthesized ceramics.The results showed that the ceramic with a BN content of 12wt%showed the best processability,but had diminished mechanical properties(such as fracture toughness and bending strength).The ceramic with a BN content of 9wt%showed better processability than those with 3wt%and 6wt%BN.However,the fracture toughness was affected by the addition of 9wt%BN,making this ceramic only usable as a base material for a three-unit fixed bridge.In contrast,the ceramics with a BN content of 3wt%or 6wt%fulfilled the criteria for use in multi-unit restoration,but their low processability made them unsuitable for milling after sintering.展开更多
基金supported by Major Instrument Projects of Sichuan Province.
文摘The Chinese Academy of Engineering Physics Terahertz Free Electron Laser Facility(CAEP THz FEL,CTFEL)is the only high-average power free electron laser terahertz source based on superconducting accelerators in China.The update of the CTFEL is now undergoing and will expand the frequency range from 0.1–4.2 THz to 0.1–125 THz.Two experimental stations for material spectroscopy and biomedicine will be built.A high harmonic generation(HHG)lightsource based beamline at the material spectroscopy experimental station for time-resolved angle-resolved photoemission spectroscopy(ARPES)research will be constructed and the optical design is presented.The HHG lightsource covers the extreme ultraviolet(XUV)photon energy range of 20–50 eV.A Czerny–Turner monochromator with two plane gratings worked in conical diffraction configuration is employed to maintain the transmission efficiency and preserve the pulse time duration.The calculated beamline transmission efficiency is better than 5%in the whole photon energy range.To our knowledge,this is the first time in China to combine THz-infrared FEL with HHG light source,and this experimental station will be a powerful and effective instrument that will give new research opportunities in the future for users doing research on the dynamic evolution of the excited electron band structure of a material’s surface.
基金Capital Health Development Research Special Project,No.2020-4-5123.
文摘BACKGROUND Peutz-Jeghers syndrome(PJS)has brought significant physical,psychological and economic burdens on the patients and their families due to its early onset,diagnostic and therapeutic challenges and increased recurrence risk.AIM To explore the current research status and emerging hotspots of PJS.METHODS Studies on PJS published during 1994-2023 were gathered based on Web of Science Core Collection.Additionally,a case of PJS-induced intestinal intussusception,successfully treated with endoscopic methods despite three laparotomies,was highlighted.Comprehensive bibliometric and visual analysis were conducted with VOSviewer,R and CiteSpace.RESULTS Altogether 1760 studies were identified,indicating a steady increase in the publication number.The United States had the highest influence,whereas the University of Helsinki emerged as the leading institution,and Aaltonen LA from the University of Helsinki was the most prolific author.Cancer Research,Oncogene and Endoscopy were the top three journals based on H-index.Keyword burst direction analysis revealed that"cancer risk","management","surveillance"and"familial pancreatic cancer"were the potential hotspots for investigation.Additionally,"early detection","capsule endoscopy","clinical management","double-balloon endoscopy","familial pancreatic cancer"and"molecular genetic basis"were identified as the key clusters of co-cited references.Endoscopic polypectomy remained effective on resolving intestinal intussusception in patients who underwent three previous laparotomies.CONCLUSION In the last three decades,global publications related to PJS show a steadily increasing trend in number.Endoscopic management is currently a research hotspot.
基金financially supported by the National Natural Science Foundation of China(No.81371183).
文摘3Y-TZP/3wt%Al_(2)O_(3) powder was coated with varying amounts of BN using the urea and borate reaction sintering method,and then multiphase ceramics were prepared by hot pressing sintering.The micro-topography and the compositional analysis of synthesized ceramics were conducted through scanning electron microscopy,transmission electron microscopy and X-ray diffraction.A mechanical tester was used to analyze the Vickers hardness,fracture toughness,and bending strength of the synthesized ceramics.The results showed that the ceramic with a BN content of 12wt%showed the best processability,but had diminished mechanical properties(such as fracture toughness and bending strength).The ceramic with a BN content of 9wt%showed better processability than those with 3wt%and 6wt%BN.However,the fracture toughness was affected by the addition of 9wt%BN,making this ceramic only usable as a base material for a three-unit fixed bridge.In contrast,the ceramics with a BN content of 3wt%or 6wt%fulfilled the criteria for use in multi-unit restoration,but their low processability made them unsuitable for milling after sintering.
