Luminescent properties of Er^(3+)-and Yb^(3+)-co-doped CaF_(2)upconversion nanoparticles(UCNPs)were investigated in single particle and densely-packed states with a custom-built microscope.The single UCNPs exhibit lin...Luminescent properties of Er^(3+)-and Yb^(3+)-co-doped CaF_(2)upconversion nanoparticles(UCNPs)were investigated in single particle and densely-packed states with a custom-built microscope.The single UCNPs exhibit linear dependency of luminescent intensity on excitation power while the densely-packed UCNPs exhibit a 2-order power law-dependency indicating a two-photon absorption process.Time-domain luminescence intensity measurements were performed and the curves were fitted to excitationnemission rate functions based on a simplified three-state model.The results indicate that the intermediates in single particles are much less and saturated in a short time,and there are strong couplings of the ground states and intermediate states between neighboring UCNPs in densely packed UCNPs.展开更多
This study was designed to investigate the protective effects of Astaxanthin(AST)in rats with diabetes mellitus(DM)induced by streptozotocin.SD rats were divided into control group(n=5,only received normal saline),DM ...This study was designed to investigate the protective effects of Astaxanthin(AST)in rats with diabetes mellitus(DM)induced by streptozotocin.SD rats were divided into control group(n=5,only received normal saline),DM group(n=8)and AST+DM group(n=8;AST:50 mg/kg/day).DM rats were induced by intraperitoneal injection of streptozocin(STZ,65 mg/kg).Blood glucose level and body weight were determined at weeks 0,2,4,6 and 8,respectively.At week 8,kidney function was determined,together with expression of P53 and dynamin-related protein-1(Drp1)by Western blot analysis and immunofluorescence.AST led to increase of body weight in rats with DM.AST+DM group showed a significant decrease in blood glucose level at week 4 compared with DM group(P<0.05).AST improved renal function and significantly reduced expression of P53 and Drp1 in DM rats.In addition,AST can effectively reduce the blood glucose in DM rats,and delayed the pathogenesis of diabetic nephropathy.Such delay mediated by AST may be associated with the downregulation of Drp1 and P53.展开更多
The authors consider the problem of on-line scheduling of unit execution time jobs on uniform machines with rejection penalty. The jobs arrive one by one and can be either accepted and scheduled, or be rejected. The o...The authors consider the problem of on-line scheduling of unit execution time jobs on uniform machines with rejection penalty. The jobs arrive one by one and can be either accepted and scheduled, or be rejected. The objective is to minimize the total completion time of the accepted jobs and the total penalty of the rejection jobs. The authors propose an on-line algorithm and prove that the competitive ratio is 1/2 (2 W √3) ≈ 1.86602.展开更多
基金The work was supported by the National Key Research and Development Program of China(YFC20170110100)the National Natural Science Foundation of China(NSFC)(Grant Nos.61475185 and 11504409)Natural Science Foundation of Tianjin City(TJNSF)(Grant No.16JCYBJC43800).Xiaohu Chen and Zhengyu Gui contributed equality to this work.
文摘Luminescent properties of Er^(3+)-and Yb^(3+)-co-doped CaF_(2)upconversion nanoparticles(UCNPs)were investigated in single particle and densely-packed states with a custom-built microscope.The single UCNPs exhibit linear dependency of luminescent intensity on excitation power while the densely-packed UCNPs exhibit a 2-order power law-dependency indicating a two-photon absorption process.Time-domain luminescence intensity measurements were performed and the curves were fitted to excitationnemission rate functions based on a simplified three-state model.The results indicate that the intermediates in single particles are much less and saturated in a short time,and there are strong couplings of the ground states and intermediate states between neighboring UCNPs in densely packed UCNPs.
基金This study was supported by Yantai Science and Technology Plan Project[Grant No.2018ZHGY088].
文摘This study was designed to investigate the protective effects of Astaxanthin(AST)in rats with diabetes mellitus(DM)induced by streptozotocin.SD rats were divided into control group(n=5,only received normal saline),DM group(n=8)and AST+DM group(n=8;AST:50 mg/kg/day).DM rats were induced by intraperitoneal injection of streptozocin(STZ,65 mg/kg).Blood glucose level and body weight were determined at weeks 0,2,4,6 and 8,respectively.At week 8,kidney function was determined,together with expression of P53 and dynamin-related protein-1(Drp1)by Western blot analysis and immunofluorescence.AST led to increase of body weight in rats with DM.AST+DM group showed a significant decrease in blood glucose level at week 4 compared with DM group(P<0.05).AST improved renal function and significantly reduced expression of P53 and Drp1 in DM rats.In addition,AST can effectively reduce the blood glucose in DM rats,and delayed the pathogenesis of diabetic nephropathy.Such delay mediated by AST may be associated with the downregulation of Drp1 and P53.
基金the National Natural Science Foundation of China under Grant No.10671108
文摘The authors consider the problem of on-line scheduling of unit execution time jobs on uniform machines with rejection penalty. The jobs arrive one by one and can be either accepted and scheduled, or be rejected. The objective is to minimize the total completion time of the accepted jobs and the total penalty of the rejection jobs. The authors propose an on-line algorithm and prove that the competitive ratio is 1/2 (2 W √3) ≈ 1.86602.