The lack of Birkhoff theorem in finite-range gravitation reveals nonzero acceleration of the test body inside the massive spherical shell, as well as breakdown of screening inside the charged conductor gives rise to a...The lack of Birkhoff theorem in finite-range gravitation reveals nonzero acceleration of the test body inside the massive spherical shell, as well as breakdown of screening inside the charged conductor gives rise to acceleration of the test charge. An application of this effect to the motion of galaxies in Local Group allows to constraint quintessence parameter in some massive gravitational theories.展开更多
In a prospective study, 42 048 adults residing in Zhongshan City, Guangdong, China, were followed for 16 years, and 171 of them developed nasopharyngeal carcinoma (NPC). Although Epstein-Barr virus (EBV) antibody leve...In a prospective study, 42 048 adults residing in Zhongshan City, Guangdong, China, were followed for 16 years, and 171 of them developed nasopharyngeal carcinoma (NPC). Although Epstein-Barr virus (EBV) antibody levels of the cohort fluctuated, the antibody levels of 93% of the patients with NPC were raised and maintained at high levels for up to 10 years prior to diagnosis. This suggests that the serologic window affords an opportunity to monitor tumor progression during the preclinical stage of NPC development, facilitating early NPC detection. We reviewed the clinical records of the 171 patients with NPC in the prospective study to assess the efficacy of early NPC detection by serologic screening and clinical examination. Of the 171 patients, 51 had Stage I tumor (44 were among the 73 patients detected by clinical examination and 7 were among the 98 patients presented to outpatient department). Initial serologic screening predicted 58 (95.1%) of the 61 patients detected within 2 years. The risk of the screened population (58/3093) raised 13 times relative to cohort (61/42 048) during this period. Clinical examination detected all the 58 predicted cases, and 35 (60.3%) of which were diagnosed with Stage I tumor. The serologic prediction rate fell to 33.6% (37/110) 2 to 16 years after screening. The proportion of cases detected by clinical examination fell to 40.5% (15/37). The proportion of Stage I tumors among the cases detected by clinical examination during both periods remained at about 60%. We concluded that early detection of NPC can be accomplished by repeated serologic screening to maintain high prediction rates and by promptly examining screened subjects to detect tumors before the symptoms develop.展开更多
Dynamic response of the screen mesh is of great significance in the optimum vibrating screen design.In this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of...Dynamic response of the screen mesh is of great significance in the optimum vibrating screen design.In this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of the screen mesh is explored and the mechanism is revealed on the particle level.Firstly,a virtual experiment on a linear vibrating screen was carried out to analyze the screening pa-rameters'effect with both impact load and sustained stress inflicted on the screen mesh.Then,the time-domain evolution regularity of the screen mesh LVA(Local Vibration Amplitude)under different particle plugging conditions was investigated based on the co-simulation.Finally,the influence of screening parameters on LVA and its distribution was discussed.The results show that the screening parameters can greatly affect the screen mesh LVA and its distribution by changing the movement of the granular material and the particle penetration probability,which provides an important basis for the optimal design of the screen mesh and its supporting structure.展开更多
目的:建立石家庄地区人群早孕期和中孕期唐氏综合征筛查血清标志物的中位数,探讨本地化的唐氏筛查血清指标中位数方程对筛查效率的影响并分析其临床价值。方法:收集2017年1月至2018年11月期间的28930名孕妇的早孕期和中孕期产前筛查数据...目的:建立石家庄地区人群早孕期和中孕期唐氏综合征筛查血清标志物的中位数,探讨本地化的唐氏筛查血清指标中位数方程对筛查效率的影响并分析其临床价值。方法:收集2017年1月至2018年11月期间的28930名孕妇的早孕期和中孕期产前筛查数据,分析妊娠相关蛋白-A(PAPP-A)、游离人绒毛膜促性腺激素β亚基(Free hCGβ)、甲胎蛋白(AFP)、游离雌三醇(uE3)、NT值等指标的软件中位数和本地中位数的差异;分别利用软件中位数和本地中位数对上述筛查数据进行唐氏综合征风险评估,比较筛查效率的差异。结果:1.在石家庄地区人群中,PAPP-A、Free hCGβ、uE3的浓度值中位数均高于软件自带的高加索人群的浓度值中位数,差异有统计学意义(P<0.05);AFP的浓度值中位数在两组人群中的差异无统计学意义(P>0.05)。2.早、中孕期产前筛查血清指标的中位数倍数(multiple of median,MoM)值中值在本地中位数方程和软件中位数方程中的差异有统计学意义(P<0.05)。3.利用本地人群中位数方程评估21三体综合征高风险率为2.33%,检出率为94.59%;利用软件内置中位数评估21三体综合征的高风险率为2.16%,检出率为86.48%,差异有统计学意义(P<0.05)。结论:石家庄地区人群的早、中孕期产前筛查血清标志物中位数和软件自带的高加索人群存在显著差异;本地人群早、中孕期唐氏筛查血清标志物中位数的应用能够显著提高产筛效率;建立石家庄地区人群的早、中孕期产前筛查血清标志物中位数数据库对于本地区产前筛查工作的开展有着十分重要的意义。展开更多
文摘The lack of Birkhoff theorem in finite-range gravitation reveals nonzero acceleration of the test body inside the massive spherical shell, as well as breakdown of screening inside the charged conductor gives rise to acceleration of the test charge. An application of this effect to the motion of galaxies in Local Group allows to constraint quintessence parameter in some massive gravitational theories.
基金supported by National Natural Science Foundation of China (No. 75-61-02-13, 85-914-01-08, 96-906-01-03)
文摘In a prospective study, 42 048 adults residing in Zhongshan City, Guangdong, China, were followed for 16 years, and 171 of them developed nasopharyngeal carcinoma (NPC). Although Epstein-Barr virus (EBV) antibody levels of the cohort fluctuated, the antibody levels of 93% of the patients with NPC were raised and maintained at high levels for up to 10 years prior to diagnosis. This suggests that the serologic window affords an opportunity to monitor tumor progression during the preclinical stage of NPC development, facilitating early NPC detection. We reviewed the clinical records of the 171 patients with NPC in the prospective study to assess the efficacy of early NPC detection by serologic screening and clinical examination. Of the 171 patients, 51 had Stage I tumor (44 were among the 73 patients detected by clinical examination and 7 were among the 98 patients presented to outpatient department). Initial serologic screening predicted 58 (95.1%) of the 61 patients detected within 2 years. The risk of the screened population (58/3093) raised 13 times relative to cohort (61/42 048) during this period. Clinical examination detected all the 58 predicted cases, and 35 (60.3%) of which were diagnosed with Stage I tumor. The serologic prediction rate fell to 33.6% (37/110) 2 to 16 years after screening. The proportion of cases detected by clinical examination fell to 40.5% (15/37). The proportion of Stage I tumors among the cases detected by clinical examination during both periods remained at about 60%. We concluded that early detection of NPC can be accomplished by repeated serologic screening to maintain high prediction rates and by promptly examining screened subjects to detect tumors before the symptoms develop.
基金supported by the Unveils Major Projects of Hubei Province (grant No.2019AEE015).
文摘Dynamic response of the screen mesh is of great significance in the optimum vibrating screen design.In this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of the screen mesh is explored and the mechanism is revealed on the particle level.Firstly,a virtual experiment on a linear vibrating screen was carried out to analyze the screening pa-rameters'effect with both impact load and sustained stress inflicted on the screen mesh.Then,the time-domain evolution regularity of the screen mesh LVA(Local Vibration Amplitude)under different particle plugging conditions was investigated based on the co-simulation.Finally,the influence of screening parameters on LVA and its distribution was discussed.The results show that the screening parameters can greatly affect the screen mesh LVA and its distribution by changing the movement of the granular material and the particle penetration probability,which provides an important basis for the optimal design of the screen mesh and its supporting structure.
基金Supported by National High Technology Research and Development Program of China （863 Program） （2007AA809502C） National Natural Science Foundation of China （50979093） Program for New Century Excellent Talents in University （NCET-06-0877）
文摘目的:建立石家庄地区人群早孕期和中孕期唐氏综合征筛查血清标志物的中位数,探讨本地化的唐氏筛查血清指标中位数方程对筛查效率的影响并分析其临床价值。方法:收集2017年1月至2018年11月期间的28930名孕妇的早孕期和中孕期产前筛查数据,分析妊娠相关蛋白-A(PAPP-A)、游离人绒毛膜促性腺激素β亚基(Free hCGβ)、甲胎蛋白(AFP)、游离雌三醇(uE3)、NT值等指标的软件中位数和本地中位数的差异;分别利用软件中位数和本地中位数对上述筛查数据进行唐氏综合征风险评估,比较筛查效率的差异。结果:1.在石家庄地区人群中,PAPP-A、Free hCGβ、uE3的浓度值中位数均高于软件自带的高加索人群的浓度值中位数,差异有统计学意义(P<0.05);AFP的浓度值中位数在两组人群中的差异无统计学意义(P>0.05)。2.早、中孕期产前筛查血清指标的中位数倍数(multiple of median,MoM)值中值在本地中位数方程和软件中位数方程中的差异有统计学意义(P<0.05)。3.利用本地人群中位数方程评估21三体综合征高风险率为2.33%,检出率为94.59%;利用软件内置中位数评估21三体综合征的高风险率为2.16%,检出率为86.48%,差异有统计学意义(P<0.05)。结论:石家庄地区人群的早、中孕期产前筛查血清标志物中位数和软件自带的高加索人群存在显著差异;本地人群早、中孕期唐氏筛查血清标志物中位数的应用能够显著提高产筛效率;建立石家庄地区人群的早、中孕期产前筛查血清标志物中位数数据库对于本地区产前筛查工作的开展有着十分重要的意义。
