This meta-analysis compared the therapeutic effect of cable pin system(CPS) with K-wire tension band(KTB) in the treatment of patella fractures among Chinese Han population. The databases of PubM ed, Cochrane libr...This meta-analysis compared the therapeutic effect of cable pin system(CPS) with K-wire tension band(KTB) in the treatment of patella fractures among Chinese Han population. The databases of PubM ed, Cochrane library, China National Knowledge Infrastructure(CNKI), Chinese Wan Fang and Chinese VIP were searched for studies on CPS versus KTB in the treatment of patella fractures among Chinese Han population. Literatures were screened according to the inclusion and exclusion criteria. The quality of the studies was assessed, and meta-analysis was performed using the Cochrane Collaboration's REVMAN 5.3 software. A total of 932 patients from 15 studies were included in this meta-analysis(426 fractures treated with CPS and 506 fractures treated with KTB). There were significant differences in duration of hospital stay [mean difference(MD)=–1.07; 95% confidence interval(CI): –1.71 to –0.43], fracture healing time(MD=–1.23; 95% CI: –1.68 to –0.77), flexion degree of knee joint at 6 th month after operation(MD=14.82; 95% CI: 10.93 to 18.71), incidence of postoperative complication [risk ratio(RR)=0.16; 95% CI: 0.09 to 0.27] and excellent-good rate of B?stman score(RR=1.09; 95% CI: 1.03 to 1.16) between the CPS group and KTB group, while no significant difference was found in operative time between the two groups(MD=–4.52; 95% CI: –11.70 to 2.67). For the treatment of patella fractures among Chinese Han population, limited evidence suggests that the CPS is more suitable than the KTB when considering the hospital stay, fracture healing time, flexion degree of knee at 6 th month after operation, incidence of postoperative complication and excellent-good rate of B?stman joint score. Due to the limitation of high quality evidence and sample size, more large-scale randomized controlled trials are needed to validate the findings in the future.展开更多
A theoretical model of flatband voltage (VFB) of metal/high-k/Si02/Si stack is proposed based on band alignment of entire gate stack, i.e., the VFB is obtained by simultaneously considering band alignments of metal/...A theoretical model of flatband voltage (VFB) of metal/high-k/Si02/Si stack is proposed based on band alignment of entire gate stack, i.e., the VFB is obtained by simultaneously considering band alignments of metal/high-k, high-k/SiO2 and SiO2/Si interfaces, and their interactions. Then the VFB of TiN/HfO2/SiO2/Si stack is experimentally obtained and theoretically investigated by this model. The theoretical calculations are in good agreement with the experimental results. Furthermore, both positive VFB shift of TiN/HfO2/SiO2/Si stack and Fermi level pinning are successfully interpreted and attributed to the dielectric contact induced gap states at TiN/HfO2 and HfO2/SiO2 interfaces.展开更多
After constructing a stress and strain model, the valence bands of in-plane biaxial tensile strained Si is calculated by k·p method. In the paper we calculate the accurate anisotropy valance bands and the splitti...After constructing a stress and strain model, the valence bands of in-plane biaxial tensile strained Si is calculated by k·p method. In the paper we calculate the accurate anisotropy valance bands and the splitting energy between light and heavy hole bands. The results show that the valance bands are highly distorted, and the anisotropy is more obvious. To obtain the density of states (DOS) effective mass, which is a very important parameter for device modeling, a DOS effective mass model of biaxial tensile strained Si is constructed based on the valance band calculation. This model can be directly used in the device model of metal-oxide semiconductor field effect transistor (MOSFET). It also a provides valuable reference for biaxial tensile strained silicon MOSFET design.展开更多
In metal-gate/high-k stacks adopted by the 45 nm technology node, the fiat-band voltage (Vfb) shift remains one of the most critical challenges, particularly the flat-band voltage roll-off (Vfb roll-off) phenomeno...In metal-gate/high-k stacks adopted by the 45 nm technology node, the fiat-band voltage (Vfb) shift remains one of the most critical challenges, particularly the flat-band voltage roll-off (Vfb roll-off) phenomenon in p-channel metal- oxide-semiconductor (pMOS) devices with an ultrathin oxide layer. In this paper, recent progress on the investigation of the Vfb shift and the origin of the Vfb roll-off in the metal-gate/high-k pMOS stacks are reviewed. Methods that can alleviate the Vfb shift phenomenon are summarized and the future research trend is described.展开更多
研制了一款K波段(23~25 GHz)收发一体化多功能芯片。该芯片集成了单刀双掷开关(SPDT)、接收支路低噪声放大器和发射支路高效率功率放大器。为兼顾低噪声和高效率功率特性,对电路的拓扑结构进行了优化选择和设计。在器件特征工作频点,采...研制了一款K波段(23~25 GHz)收发一体化多功能芯片。该芯片集成了单刀双掷开关(SPDT)、接收支路低噪声放大器和发射支路高效率功率放大器。为兼顾低噪声和高效率功率特性,对电路的拓扑结构进行了优化选择和设计。在器件特征工作频点,采用开关模型、噪声模型和非线性大信号模型进行联合仿真设计。测试结果表明,该收发一体多功能芯片在23~25 GHz范围内,接收支路增益23 d B、噪声系数2.5 d B,工作电流仅为12 m A;发射支路增益为30 d B,1 d B压缩点输出功率为18.7 d Bm,功率附加效率达到30%,动态电流仅为70 m A。芯片尺寸小,仅为3.5 mm×2.5 mm。展开更多
文摘This meta-analysis compared the therapeutic effect of cable pin system(CPS) with K-wire tension band(KTB) in the treatment of patella fractures among Chinese Han population. The databases of PubM ed, Cochrane library, China National Knowledge Infrastructure(CNKI), Chinese Wan Fang and Chinese VIP were searched for studies on CPS versus KTB in the treatment of patella fractures among Chinese Han population. Literatures were screened according to the inclusion and exclusion criteria. The quality of the studies was assessed, and meta-analysis was performed using the Cochrane Collaboration's REVMAN 5.3 software. A total of 932 patients from 15 studies were included in this meta-analysis(426 fractures treated with CPS and 506 fractures treated with KTB). There were significant differences in duration of hospital stay [mean difference(MD)=–1.07; 95% confidence interval(CI): –1.71 to –0.43], fracture healing time(MD=–1.23; 95% CI: –1.68 to –0.77), flexion degree of knee joint at 6 th month after operation(MD=14.82; 95% CI: 10.93 to 18.71), incidence of postoperative complication [risk ratio(RR)=0.16; 95% CI: 0.09 to 0.27] and excellent-good rate of B?stman score(RR=1.09; 95% CI: 1.03 to 1.16) between the CPS group and KTB group, while no significant difference was found in operative time between the two groups(MD=–4.52; 95% CI: –11.70 to 2.67). For the treatment of patella fractures among Chinese Han population, limited evidence suggests that the CPS is more suitable than the KTB when considering the hospital stay, fracture healing time, flexion degree of knee at 6 th month after operation, incidence of postoperative complication and excellent-good rate of B?stman joint score. Due to the limitation of high quality evidence and sample size, more large-scale randomized controlled trials are needed to validate the findings in the future.
基金supported by the National Natural Science of China(Grant Nos.61176091 and 50932001)
文摘A theoretical model of flatband voltage (VFB) of metal/high-k/Si02/Si stack is proposed based on band alignment of entire gate stack, i.e., the VFB is obtained by simultaneously considering band alignments of metal/high-k, high-k/SiO2 and SiO2/Si interfaces, and their interactions. Then the VFB of TiN/HfO2/SiO2/Si stack is experimentally obtained and theoretically investigated by this model. The theoretical calculations are in good agreement with the experimental results. Furthermore, both positive VFB shift of TiN/HfO2/SiO2/Si stack and Fermi level pinning are successfully interpreted and attributed to the dielectric contact induced gap states at TiN/HfO2 and HfO2/SiO2 interfaces.
基金supported by the National Natural Science Foundation of China (Grant Nos. 60976068 and 60936005)the Cultivation Fund of the Key Scientific and Technical Innovation Project,Ministry of Education of China (Grant No. 78083)
文摘After constructing a stress and strain model, the valence bands of in-plane biaxial tensile strained Si is calculated by k·p method. In the paper we calculate the accurate anisotropy valance bands and the splitting energy between light and heavy hole bands. The results show that the valance bands are highly distorted, and the anisotropy is more obvious. To obtain the density of states (DOS) effective mass, which is a very important parameter for device modeling, a DOS effective mass model of biaxial tensile strained Si is constructed based on the valance band calculation. This model can be directly used in the device model of metal-oxide semiconductor field effect transistor (MOSFET). It also a provides valuable reference for biaxial tensile strained silicon MOSFET design.
基金Project supported by the National Natural Science Foundation of China (Grants Nos.50802005 and 11074020)the Program for New Century Excellent Talents in University,China (Grant No.NCET-08-0029)+1 种基金the Ph.D.Program Foundation of Ministry of Education of China (Grant No.200800061055)the Hong Kong Research Grants Council General Research Funds,China (Grant No.CityU112608)
文摘In metal-gate/high-k stacks adopted by the 45 nm technology node, the fiat-band voltage (Vfb) shift remains one of the most critical challenges, particularly the flat-band voltage roll-off (Vfb roll-off) phenomenon in p-channel metal- oxide-semiconductor (pMOS) devices with an ultrathin oxide layer. In this paper, recent progress on the investigation of the Vfb shift and the origin of the Vfb roll-off in the metal-gate/high-k pMOS stacks are reviewed. Methods that can alleviate the Vfb shift phenomenon are summarized and the future research trend is described.
文摘研制了一款K波段(23~25 GHz)收发一体化多功能芯片。该芯片集成了单刀双掷开关(SPDT)、接收支路低噪声放大器和发射支路高效率功率放大器。为兼顾低噪声和高效率功率特性,对电路的拓扑结构进行了优化选择和设计。在器件特征工作频点,采用开关模型、噪声模型和非线性大信号模型进行联合仿真设计。测试结果表明,该收发一体多功能芯片在23~25 GHz范围内,接收支路增益23 d B、噪声系数2.5 d B,工作电流仅为12 m A;发射支路增益为30 d B,1 d B压缩点输出功率为18.7 d Bm,功率附加效率达到30%,动态电流仅为70 m A。芯片尺寸小,仅为3.5 mm×2.5 mm。