The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 3...The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs factory.In its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs bosons.Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of magnitude.This Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering aspects.Additionally,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection procedures.Construction is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 years.The commencement of experiments and data collection could potentially be initiated in the mid-2030s.展开更多
Objective: To understand the correlation between different degrees of obesity and bone mineral density (BMD). Methods: 772 cases (300 men and 472 females) of Zhuang over 40 years old were randomly selected. The BMD an...Objective: To understand the correlation between different degrees of obesity and bone mineral density (BMD). Methods: 772 cases (300 men and 472 females) of Zhuang over 40 years old were randomly selected. The BMD and T score were calculated by measuring the right heel bone using a quantitative-ultrasound densitometer. Body composition index of body weight, waist circumference (WC), waist height ratio (WtHR), body fat percentage (BFP) and visceral fat (VF) were measured using a bioelectrical impedance method. Results: The BMI, WC, and WtHR of the male osteoporosis group were lower than those of the normal bone mass (NBM) group (P Conclusion: BMI is positively correlated with BMD in Zhuang. BFP has a greater correlation with female BMD, and a small reduction in BFP can result in a significant decrease in BMD. BMD of male was positively correlated with abdominal obesity indicators (WC, WtHR, VF). However, abdominal obesity has no obvious effect on the promotion of BMD in women, and increased WtHR can lead to a decrease in BMD. Zhuang can appropriately increase the amount of fat within the normal weight range. At the same time, reasonable exercise and balanced nutrition to avoid excessive obesity or low body weight can reduce the incidence of osteoporosis and osteoporosis fractures.展开更多
基金support from diverse funding sources,including the National Key Program for S&T Research and Development of the Ministry of Science and Technology(MOST),Yifang Wang's Science Studio of the Ten Thousand Talents Project,the CAS Key Foreign Cooperation Grant,the National Natural Science Foundation of China(NSFC)Beijing Municipal Science&Technology Commission,the CAS Focused Science Grant,the IHEP Innovation Grant,the CAS Lead Special Training Programthe CAS Center for Excellence in Particle Physics,the CAS International Partnership Program,and the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs factory.In its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs bosons.Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of magnitude.This Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering aspects.Additionally,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection procedures.Construction is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 years.The commencement of experiments and data collection could potentially be initiated in the mid-2030s.
文摘Objective: To understand the correlation between different degrees of obesity and bone mineral density (BMD). Methods: 772 cases (300 men and 472 females) of Zhuang over 40 years old were randomly selected. The BMD and T score were calculated by measuring the right heel bone using a quantitative-ultrasound densitometer. Body composition index of body weight, waist circumference (WC), waist height ratio (WtHR), body fat percentage (BFP) and visceral fat (VF) were measured using a bioelectrical impedance method. Results: The BMI, WC, and WtHR of the male osteoporosis group were lower than those of the normal bone mass (NBM) group (P Conclusion: BMI is positively correlated with BMD in Zhuang. BFP has a greater correlation with female BMD, and a small reduction in BFP can result in a significant decrease in BMD. BMD of male was positively correlated with abdominal obesity indicators (WC, WtHR, VF). However, abdominal obesity has no obvious effect on the promotion of BMD in women, and increased WtHR can lead to a decrease in BMD. Zhuang can appropriately increase the amount of fat within the normal weight range. At the same time, reasonable exercise and balanced nutrition to avoid excessive obesity or low body weight can reduce the incidence of osteoporosis and osteoporosis fractures.
