The presence of matrix metalloproteinase-2 (MMP-2) in dentin has been reported, but its distribution and activity level in mature human coronal dentin are not well understood. The purpose of this study was to determin...The presence of matrix metalloproteinase-2 (MMP-2) in dentin has been reported, but its distribution and activity level in mature human coronal dentin are not well understood. The purpose of this study was to determine the MMP-2 distribution and relative activity in demineralized dentin. Crowns of twenty eight human molars were sectioned into inner (ID), middle (MD), and outer dentin (OD) regions and demineralized. MMP-2 was extracted with 0.33 mol·L -1 EDTA/2 mol·L -1 guanidine-HCl, pH 7.4, and MMP-2 concentration was estimated with enzyme-linked immunoabsorbant assay (ELISA). Further characterization was accomplished by Western blotting analysis and gelatin zymography. The mean concentrations of MMP-2 per mg dentin protein in the dentin regions were significantly different (P=0.043): 0.9 ng (ID), 0.4 ng (MD), and 2.2 ng (OD), respectively. The pattern of MMP-2 concentration was OD>ID>MD. Western blotting analysis detected ～66 and ～72 kDa immunopositive proteins corresponding to pro-and mature MMP-2, respectively, in the ID and MD, and a ～66 kDa protein in the OD. Gelatinolytic activity consistent with MMP-2 was detected in all regions. Interestingly, the pattern of levels of Western blot immunodetection and gelatinolytic activity was MD>ID>OD. The concentration of MMP-2 in human coronal dentin was highest in the region of dentin that contains the dentinoenamel junction and least in the middle region of dentin. However, levels of Western blot immunodetection and gelatinolytic activity did not correlate with the estimated regional concentrations of MMP-2, potentially indicating region specific protein interactions.展开更多
Efficient multi-machine cooperation and network dynamics still remain open that jeopardize great applications in largescale machine-to-machine(M2M) networks. Among all possible machine cooperation controls, to synchro...Efficient multi-machine cooperation and network dynamics still remain open that jeopardize great applications in largescale machine-to-machine(M2M) networks. Among all possible machine cooperation controls, to synchronize tremendous machines in a timing-efficient brings one of the greatest challenge and serves as the foundation for any other network control policies. In this paper, we propose a linear-time synchronization protocol in large M2M networks. Specifically, a closed-form of synchronization rate is provided by developing the statistical bounds of the second smallest eigenvalue of the graph Laplacian matrix. These bounds enable the efficient control of network dynamics, facilitating the timing synchronization in networks. Through a practical study in Metropolis, simulation results confirm our theoretical analysis and provide effective selection of wireless technologies, including Zigbee, Wi-Fi, and cellular systems, with respect to the deployed density of machines. Therefore, this paper successfully demonstrates a practical timing synchronization, to make a breakthrough of network dynamic control in real-world machine systems, such as Internet of Things.展开更多
Quasi-two-dimensional(quasi-2D)perovskites are promising materials for potential application in light-emitting diodes(LEDs)due to their high exciton binding energy and efficient emission.However,their luminescent perf...Quasi-two-dimensional(quasi-2D)perovskites are promising materials for potential application in light-emitting diodes(LEDs)due to their high exciton binding energy and efficient emission.However,their luminescent performance is limited by the low-n phases that act as quenching luminescence centers.Here,a novel strategy for eliminating low-n phases is proposed based on the doping of strontium bromide(SrBr_(2))in perovskites,in which SrBr_(2)is able to manipulate the growth of quasi-2D perovskites during their formation.It was reasonably inferred that SrBr_(2)readily dissociated strontium ions(Sr^(2+))in dimethyl sulfoxide solvent,and Sr^(2+)was preferentially adsorbed around[PbBr_(6)]^(4−)through strong electrostatic interaction between them,leading to a controllable growth of quasi-2D perovskites by appropriately increasing the formation energy of perovskites.It has been experimentally proved that the growth can almost completely eliminate low-n phases of quasi-2D perovskite films,which exhibited remarkably enhanced photoluminescence.A high electroluminescent efficiency matrix green quasi-2D perovskite-LED(PeLED)with a pixel density of 120 pixels per inch fabricated by inkjet printing technique was achieved,exhibiting a peak external quantum efficiency of 13.9%,which is the most efficient matrix green quasi-2D PeLED so far to our knowledge.展开更多
By begiwhng with the Cannon algorithm[1] and the double- direct ion dat amoving algoritlun[2] for processors arranged as a 2-D square mesh, we improvethese two algorithms to general 2-D mesh in this paper. We also con...By begiwhng with the Cannon algorithm[1] and the double- direct ion dat amoving algoritlun[2] for processors arranged as a 2-D square mesh, we improvethese two algorithms to general 2-D mesh in this paper. We also consider theapplication of our algorithms in those operations which are similar to matrix multiplication. Using MPI parallel programming environment, we have obtained satisfactory performance on Dawning-1000.展开更多
文摘The presence of matrix metalloproteinase-2 (MMP-2) in dentin has been reported, but its distribution and activity level in mature human coronal dentin are not well understood. The purpose of this study was to determine the MMP-2 distribution and relative activity in demineralized dentin. Crowns of twenty eight human molars were sectioned into inner (ID), middle (MD), and outer dentin (OD) regions and demineralized. MMP-2 was extracted with 0.33 mol·L -1 EDTA/2 mol·L -1 guanidine-HCl, pH 7.4, and MMP-2 concentration was estimated with enzyme-linked immunoabsorbant assay (ELISA). Further characterization was accomplished by Western blotting analysis and gelatin zymography. The mean concentrations of MMP-2 per mg dentin protein in the dentin regions were significantly different (P=0.043): 0.9 ng (ID), 0.4 ng (MD), and 2.2 ng (OD), respectively. The pattern of MMP-2 concentration was OD>ID>MD. Western blotting analysis detected ～66 and ～72 kDa immunopositive proteins corresponding to pro-and mature MMP-2, respectively, in the ID and MD, and a ～66 kDa protein in the OD. Gelatinolytic activity consistent with MMP-2 was detected in all regions. Interestingly, the pattern of levels of Western blot immunodetection and gelatinolytic activity was MD>ID>OD. The concentration of MMP-2 in human coronal dentin was highest in the region of dentin that contains the dentinoenamel junction and least in the middle region of dentin. However, levels of Western blot immunodetection and gelatinolytic activity did not correlate with the estimated regional concentrations of MMP-2, potentially indicating region specific protein interactions.
基金supported by the Major Research plan of the National Natural Science Foundation of China 9118008National Key Technology R&D Program of the Ministry of Science and Technology 2014BAC16B01
文摘Efficient multi-machine cooperation and network dynamics still remain open that jeopardize great applications in largescale machine-to-machine(M2M) networks. Among all possible machine cooperation controls, to synchronize tremendous machines in a timing-efficient brings one of the greatest challenge and serves as the foundation for any other network control policies. In this paper, we propose a linear-time synchronization protocol in large M2M networks. Specifically, a closed-form of synchronization rate is provided by developing the statistical bounds of the second smallest eigenvalue of the graph Laplacian matrix. These bounds enable the efficient control of network dynamics, facilitating the timing synchronization in networks. Through a practical study in Metropolis, simulation results confirm our theoretical analysis and provide effective selection of wireless technologies, including Zigbee, Wi-Fi, and cellular systems, with respect to the deployed density of machines. Therefore, this paper successfully demonstrates a practical timing synchronization, to make a breakthrough of network dynamic control in real-world machine systems, such as Internet of Things.
基金This work was supported by the NSFC(Grant Nos.22090024 and 62074059)the Science and Technology Project of Guangdong Province(Grant No.2019B030302007).
文摘Quasi-two-dimensional(quasi-2D)perovskites are promising materials for potential application in light-emitting diodes(LEDs)due to their high exciton binding energy and efficient emission.However,their luminescent performance is limited by the low-n phases that act as quenching luminescence centers.Here,a novel strategy for eliminating low-n phases is proposed based on the doping of strontium bromide(SrBr_(2))in perovskites,in which SrBr_(2)is able to manipulate the growth of quasi-2D perovskites during their formation.It was reasonably inferred that SrBr_(2)readily dissociated strontium ions(Sr^(2+))in dimethyl sulfoxide solvent,and Sr^(2+)was preferentially adsorbed around[PbBr_(6)]^(4−)through strong electrostatic interaction between them,leading to a controllable growth of quasi-2D perovskites by appropriately increasing the formation energy of perovskites.It has been experimentally proved that the growth can almost completely eliminate low-n phases of quasi-2D perovskite films,which exhibited remarkably enhanced photoluminescence.A high electroluminescent efficiency matrix green quasi-2D perovskite-LED(PeLED)with a pixel density of 120 pixels per inch fabricated by inkjet printing technique was achieved,exhibiting a peak external quantum efficiency of 13.9%,which is the most efficient matrix green quasi-2D PeLED so far to our knowledge.
文摘By begiwhng with the Cannon algorithm[1] and the double- direct ion dat amoving algoritlun[2] for processors arranged as a 2-D square mesh, we improvethese two algorithms to general 2-D mesh in this paper. We also consider theapplication of our algorithms in those operations which are similar to matrix multiplication. Using MPI parallel programming environment, we have obtained satisfactory performance on Dawning-1000.
