AIM:To examine possible differences in clinical outcomes between sub-threshold micro-pulse diode laser photocoagulation(SDM) and traditional modified Early Treatment Diabetic Retinopathy Study(mETDRS)treatment pr...AIM:To examine possible differences in clinical outcomes between sub-threshold micro-pulse diode laser photocoagulation(SDM) and traditional modified Early Treatment Diabetic Retinopathy Study(mETDRS)treatment protocol in diabetic macuiar edema(DME).METHODS:A comprehensive literature search using the Cochrane Collaboration methodology to identify RCTs comparing SDM with mETDRS for DME.The participants were type Ⅰ or type Ⅱ diabetes mellitus with clinically significant macuiar edema treated by SDM from previously reported randomized controlled trials(RCTs).The primary outcome measures were the changes in the best corrected visual acuity(BCVA) and the central macuiar thickness(CMT) as measured by optical coherence tomography(OCT).The secondary outcomes were the contrast sensitivity and the damages of the retina.RESULTS:Seven studies were identified and analyzed for comparing SDM(215 eyes) with mETDRS(210 eyes)for DME.There were no statistical differences in the BCVA after treatment between the SDM and mETDRS based on the follow-up:3mo(MD,-0.02;95% Cl,-0.12 to 0.09;P=0.77),6mo(MD,-0.02;95% Cl,-0.12 to 0.09;P=0.75),12mo(MD,-0.05;95% Cl,-0.17 to 0.07;P=0.40).Likewise,there were no statistical differences in the CMT after treatment between the SDM and mETDRS in 3mo(MD,-9.92;95% Cl,-28.69 to 8.85;P=0.30),6mo(MD,-11.37;95% Cl,-29.65 to 6.91;P=0.22),12mo(MD,8.44;95% Cl,-29.89 to 46.77;P=0.67).Three RCTs suggested that SDM laser results in good preservation of contrast sensitivity as mETDRS,in two different followup evaluations:3mo(MD,0.05;95% Cl,0 to 0.09;P=0.04) and 6mo(MD,0.02;95% Cl,-0.10 to 0.14;P=0.78).Two RCTs showed that the SDM laser treatment did less retinal damage than that mETDRS did(OR,0.05;95% Cl,0.02 to 0.13;P〈0.01).CONCLUSION:SDM laser photocoagulation shows an equally good effect on visual acuity,contrast sensitivity,and reduction of DME as compared to conventional mETDRS protocol with less retinal damage.展开更多
Digital circuits operating in the sub-threshold regime consume the least energy. The strict energy constraints are desired in the applications which work at the lowest possible supply voltage. On the other hand, the c...Digital circuits operating in the sub-threshold regime consume the least energy. The strict energy constraints are desired in the applications which work at the lowest possible supply voltage. On the other hand, the conventional design flow utilizes the technology library provided by the foundry with a fixed voltage boundary, which causes problems when the supply scales down to the sub-threshold regime. In this paper, we present a design methodology to characterize the existing cell library with Liberty NCX to facilitate the standard design flow. It is demonstrated in 0.13 μm complementary metal-oxide-semiconductor (CMOS) technology with the supply voltage of 300 mV.展开更多
To meet the increasing demands for higher performance and low-power consumption in present and future Systems-on-Chips (SoCs) require a large amount of on-die/embedded memory. In Deep-Sub-Micron (DSM) technology, it i...To meet the increasing demands for higher performance and low-power consumption in present and future Systems-on-Chips (SoCs) require a large amount of on-die/embedded memory. In Deep-Sub-Micron (DSM) technology, it is coming as challenges, e.g., leakage power, performance, data retentation, and stability issues. In this work, we have proposed a novel low-stress SRAM cell, called as IP3 SRAM bit-cell, as an integrated cell. It has a separate write sub-cell and read sub-cell, where the write sub-cell has dual role of data write and data hold. The data read sub-cell is proposed as a pMOS gated ground scheme to further reduce the read power by lowering the gate and subthreshold leakage currents. The drowsy voltage is applied to the cell when the memory is in the standby mode. Further, it utilizes the full-supply body biasing scheme while the memory is in the standby mode, to further reduce the subthreshold leakage current to reduce the overall standby power. To the best of our knowledge, this low-stress memory cell has been proposed for the first time. The proposed IP3 SRAM Cell has a significant write and read power reduction as compared to the conventional 6 T and PP SRAM cells and overall improved read stability and write ability performances. The proposed design is being simulated at VDD = 0.8 V and 0.7 V and an analysis is presented here for 0.8 V to adhere previously reported works. The other design parameters are taken from the CMOS technology available on 45 nm with tOX = 2.4 nm, Vthn = 0.224 V, and Vthp = 0.24 V at T = 27?C.展开更多
分析了工作在亚阈值区、线性区和饱和区的MOS晶体管不同电流特性,设计了一种低功耗全MOS基准电压源电路。使用工作在线性区的MOS晶体管代替普通常规电阻,使整个电路实现全MOS基准源的特性,同时有效减小电路芯片面积,并且输出基准电压为...分析了工作在亚阈值区、线性区和饱和区的MOS晶体管不同电流特性,设计了一种低功耗全MOS基准电压源电路。使用工作在线性区的MOS晶体管代替普通常规电阻,使整个电路实现全MOS基准源的特性,同时有效减小电路芯片面积,并且输出基准电压为线性区MOS管提供偏压以进一步降低功耗。基于SMIC 0.18μm CMOS工艺设计电路。仿真结果表明此电路在1.8 V电源电压下,–50^+150℃的温度系数为22.6×10–6/℃,基准电压源输出电压约为992 m V,25℃时静态电流为327.3 n A,电路总静态功耗为0.59μW,10 k Hz时的电源抑制比为–25.36 d B。展开更多
文摘AIM:To examine possible differences in clinical outcomes between sub-threshold micro-pulse diode laser photocoagulation(SDM) and traditional modified Early Treatment Diabetic Retinopathy Study(mETDRS)treatment protocol in diabetic macuiar edema(DME).METHODS:A comprehensive literature search using the Cochrane Collaboration methodology to identify RCTs comparing SDM with mETDRS for DME.The participants were type Ⅰ or type Ⅱ diabetes mellitus with clinically significant macuiar edema treated by SDM from previously reported randomized controlled trials(RCTs).The primary outcome measures were the changes in the best corrected visual acuity(BCVA) and the central macuiar thickness(CMT) as measured by optical coherence tomography(OCT).The secondary outcomes were the contrast sensitivity and the damages of the retina.RESULTS:Seven studies were identified and analyzed for comparing SDM(215 eyes) with mETDRS(210 eyes)for DME.There were no statistical differences in the BCVA after treatment between the SDM and mETDRS based on the follow-up:3mo(MD,-0.02;95% Cl,-0.12 to 0.09;P=0.77),6mo(MD,-0.02;95% Cl,-0.12 to 0.09;P=0.75),12mo(MD,-0.05;95% Cl,-0.17 to 0.07;P=0.40).Likewise,there were no statistical differences in the CMT after treatment between the SDM and mETDRS in 3mo(MD,-9.92;95% Cl,-28.69 to 8.85;P=0.30),6mo(MD,-11.37;95% Cl,-29.65 to 6.91;P=0.22),12mo(MD,8.44;95% Cl,-29.89 to 46.77;P=0.67).Three RCTs suggested that SDM laser results in good preservation of contrast sensitivity as mETDRS,in two different followup evaluations:3mo(MD,0.05;95% Cl,0 to 0.09;P=0.04) and 6mo(MD,0.02;95% Cl,-0.10 to 0.14;P=0.78).Two RCTs showed that the SDM laser treatment did less retinal damage than that mETDRS did(OR,0.05;95% Cl,0.02 to 0.13;P〈0.01).CONCLUSION:SDM laser photocoagulation shows an equally good effect on visual acuity,contrast sensitivity,and reduction of DME as compared to conventional mETDRS protocol with less retinal damage.
基金supported by the Important National S&T Special Project of China under Grant No.2011ZX01034-002-001-2
文摘Digital circuits operating in the sub-threshold regime consume the least energy. The strict energy constraints are desired in the applications which work at the lowest possible supply voltage. On the other hand, the conventional design flow utilizes the technology library provided by the foundry with a fixed voltage boundary, which causes problems when the supply scales down to the sub-threshold regime. In this paper, we present a design methodology to characterize the existing cell library with Liberty NCX to facilitate the standard design flow. It is demonstrated in 0.13 μm complementary metal-oxide-semiconductor (CMOS) technology with the supply voltage of 300 mV.
文摘To meet the increasing demands for higher performance and low-power consumption in present and future Systems-on-Chips (SoCs) require a large amount of on-die/embedded memory. In Deep-Sub-Micron (DSM) technology, it is coming as challenges, e.g., leakage power, performance, data retentation, and stability issues. In this work, we have proposed a novel low-stress SRAM cell, called as IP3 SRAM bit-cell, as an integrated cell. It has a separate write sub-cell and read sub-cell, where the write sub-cell has dual role of data write and data hold. The data read sub-cell is proposed as a pMOS gated ground scheme to further reduce the read power by lowering the gate and subthreshold leakage currents. The drowsy voltage is applied to the cell when the memory is in the standby mode. Further, it utilizes the full-supply body biasing scheme while the memory is in the standby mode, to further reduce the subthreshold leakage current to reduce the overall standby power. To the best of our knowledge, this low-stress memory cell has been proposed for the first time. The proposed IP3 SRAM Cell has a significant write and read power reduction as compared to the conventional 6 T and PP SRAM cells and overall improved read stability and write ability performances. The proposed design is being simulated at VDD = 0.8 V and 0.7 V and an analysis is presented here for 0.8 V to adhere previously reported works. The other design parameters are taken from the CMOS technology available on 45 nm with tOX = 2.4 nm, Vthn = 0.224 V, and Vthp = 0.24 V at T = 27?C.
文摘分析了工作在亚阈值区、线性区和饱和区的MOS晶体管不同电流特性,设计了一种低功耗全MOS基准电压源电路。使用工作在线性区的MOS晶体管代替普通常规电阻,使整个电路实现全MOS基准源的特性,同时有效减小电路芯片面积,并且输出基准电压为线性区MOS管提供偏压以进一步降低功耗。基于SMIC 0.18μm CMOS工艺设计电路。仿真结果表明此电路在1.8 V电源电压下,–50^+150℃的温度系数为22.6×10–6/℃,基准电压源输出电压约为992 m V,25℃时静态电流为327.3 n A,电路总静态功耗为0.59μW,10 k Hz时的电源抑制比为–25.36 d B。