Achieving optimal alignment in total knee arthroplasty(TKA)is a critical factor in ensuring optimal outcomes and long-term implant survival.Traditionally,mechanical alignment has been favored to achieve neutral post-o...Achieving optimal alignment in total knee arthroplasty(TKA)is a critical factor in ensuring optimal outcomes and long-term implant survival.Traditionally,mechanical alignment has been favored to achieve neutral post-operative joint alignment.However,contemporary approaches,such as kinematic alignments and hybrid techniques including adjusted mechanical,restricted kinematic,inverse kinematic,and functional alignments,are gaining attention for their ability to restore native joint kinematics and anatomical alignment,potentially leading to enhanced functional outcomes and greater patient satisfaction.The ongoing debate on optimal alignment strategies considers the following factors:long-term implant durability,functional improvement,and resolution of individual anatomical variations.Furthermore,advancements of computer-navigated and robotic-assisted surgery has augmented the precision in implant positioning and objective measurements of soft tissue balance.Despite ongoing debates on balancing implant longevity and functional outcomes,there is an increasing advocacy for personalized alignment strategies that are tailored to individual anatomical variations.This review evaluates the spectrum of various alignment techniques in TKA,including mechanical alignment,patient-specific kinematic approaches,and emerging hybrid methods.Each technique is scrutinized based on its fundamental principles,procedural techniques,inherent advantages,and potential limitations,while identifying significant clinical gaps that underscore the need for further investigation.展开更多
针对X波段50 W GaN功放管电路进行改进设计,在满足原有指标的条件下,同时提高电路工作稳定性;巧妙改变微波电路结构,去除了原电路所用的电感,并在不影响电路指标的前提下适当减少了电容、电阻的用量,为整个电路的设计节约了成本。同时,...针对X波段50 W GaN功放管电路进行改进设计,在满足原有指标的条件下,同时提高电路工作稳定性;巧妙改变微波电路结构,去除了原电路所用的电感,并在不影响电路指标的前提下适当减少了电容、电阻的用量,为整个电路的设计节约了成本。同时,仿真并制作了Wilkinson功分功合器。最终得到85 W功率放大模块,并给出了测试结果。展开更多
Effects of photoinhibition and its recovery on photosynthetic functions of winter wheat (Triticum aestivum L.) under salt stress were studied. The results showed that several parameters associated with PSⅡ functions,...Effects of photoinhibition and its recovery on photosynthetic functions of winter wheat (Triticum aestivum L.) under salt stress were studied. The results showed that several parameters associated with PSⅡ functions, e.g. Fv/Fo?Fv/Fm and qP were not influenced by lower salt concentration (200 mmol/L NaCl) while CO 2 assimilation rate decreased significantly. When exposed to higher salt concentration (400 mmol/L NaCl), PSⅡ functions were significantly inhibited which led to the decrease of carbon assimilation. These results suggest that different concentrations of salt stress affected photosynthesis by different modes. Salt stress made photosynthesis more sensitive to strong light and led to more serious photoinhibition. Under lower concentration of salt stress, the Q B-non-reductive PSⅡ reaction centers formed at the beginning of photoinhibition could be effectively used to compose active PSⅡ reaction center (RC) and repair the reversible inactivated PSⅡ RC. Under higher concentration of salt stress, PSⅡ reaction centers were seriously damaged during photoinhibition, the Q B-non-reductive PSⅡ RC could only be partly effective at the early time of photoinhibition, thus led to the accumulation of Q B-non-reductive PSⅡ RC in the course of restoration under dim light.展开更多
At the late stage of solidification with ultrasonic treatment (UST) in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification micro...At the late stage of solidification with ultrasonic treatment (UST) in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification microstructure were investigated in order to better study the mechanism of UST. It is considered that the overflowing phenomenon occurs due to the changes of vibration and flow in the remaining semisolid. Because the overflowed portion comes from the region with intense UST effect and vibrates with the probe during solidification, great modification of primary and euteetic Si (about 10 pm in length) and refinement of primary a(Al) (about 70 μm in size) are observed in this portion.展开更多
In order to improve the quality of clad ingots, diverse physical fields including electromagnetic stirring, power ultrasonic and compound field of ultrasonic and electromagnetic stirring were attempted to prepare clad...In order to improve the quality of clad ingots, diverse physical fields including electromagnetic stirring, power ultrasonic and compound field of ultrasonic and electromagnetic stirring were attempted to prepare clad ingots of 3003/4004 alloys. The solidification structures near the interface in clad ingots were investigated. The experiment results indicate that the solidification structure of 4004 alloy changes from dendritic crystals to petal-like grains when the clad ingot is treated by electromagnetic stirring. With the effect of power ultrasonic, the solidified microstructure of 4004 alloy exhibits the refinement of both primary a(A1) and eutectic silicon. Under the compound field, the primary a(A1) is refined, the morphology of eutectic silicon has a transition from a coarse plate-like form without treatment or thin acicular-like form with power ultrasonic to fine coral-like form.展开更多
The interaction between the active chips mounted and the same base plate is considered as a thermoelectrical coupling effect.An approach to coupling effect analysis of a multi-chip system is presented with IGBT as a s...The interaction between the active chips mounted and the same base plate is considered as a thermoelectrical coupling effect.An approach to coupling effect analysis of a multi-chip system is presented with IGBT as a sample.Finite element method is used to evaluate the temperature distribution in power modules.The precise electrothermal model is obtained by fitting the curve of transient thermal impedance with a finite series of exponential terms,in which,the thermal-coupling effect among chips is considered as a prediction of the highest transient temperature of the chips.This model can be used in many thermal monitoring systems.Both ANSYS and PSPICE si- mulation software have been employed,and the simulation results agree with the experimental ones very well.展开更多
A power amplifier MIC with power combining based on AlGaN/GaN HEMTs was fabricated and measured. The amplifier consists of four 10 × 120μm transistors. A Wilkinson splitters and combining were used to divide and...A power amplifier MIC with power combining based on AlGaN/GaN HEMTs was fabricated and measured. The amplifier consists of four 10 × 120μm transistors. A Wilkinson splitters and combining were used to divide and combine the power. By biasing the amplifier at VDS = 40V, IDS = 0.9A, a maximum CW output power of 41.4dBm with a maximum power added efficiency (PAE) of 32.54% and a power combine efficiency of 69% was achieved at 5.4GHz.展开更多
文摘Achieving optimal alignment in total knee arthroplasty(TKA)is a critical factor in ensuring optimal outcomes and long-term implant survival.Traditionally,mechanical alignment has been favored to achieve neutral post-operative joint alignment.However,contemporary approaches,such as kinematic alignments and hybrid techniques including adjusted mechanical,restricted kinematic,inverse kinematic,and functional alignments,are gaining attention for their ability to restore native joint kinematics and anatomical alignment,potentially leading to enhanced functional outcomes and greater patient satisfaction.The ongoing debate on optimal alignment strategies considers the following factors:long-term implant durability,functional improvement,and resolution of individual anatomical variations.Furthermore,advancements of computer-navigated and robotic-assisted surgery has augmented the precision in implant positioning and objective measurements of soft tissue balance.Despite ongoing debates on balancing implant longevity and functional outcomes,there is an increasing advocacy for personalized alignment strategies that are tailored to individual anatomical variations.This review evaluates the spectrum of various alignment techniques in TKA,including mechanical alignment,patient-specific kinematic approaches,and emerging hybrid methods.Each technique is scrutinized based on its fundamental principles,procedural techniques,inherent advantages,and potential limitations,while identifying significant clinical gaps that underscore the need for further investigation.
文摘针对X波段50 W GaN功放管电路进行改进设计,在满足原有指标的条件下,同时提高电路工作稳定性;巧妙改变微波电路结构,去除了原电路所用的电感,并在不影响电路指标的前提下适当减少了电容、电阻的用量,为整个电路的设计节约了成本。同时,仿真并制作了Wilkinson功分功合器。最终得到85 W功率放大模块,并给出了测试结果。
文摘Effects of photoinhibition and its recovery on photosynthetic functions of winter wheat (Triticum aestivum L.) under salt stress were studied. The results showed that several parameters associated with PSⅡ functions, e.g. Fv/Fo?Fv/Fm and qP were not influenced by lower salt concentration (200 mmol/L NaCl) while CO 2 assimilation rate decreased significantly. When exposed to higher salt concentration (400 mmol/L NaCl), PSⅡ functions were significantly inhibited which led to the decrease of carbon assimilation. These results suggest that different concentrations of salt stress affected photosynthesis by different modes. Salt stress made photosynthesis more sensitive to strong light and led to more serious photoinhibition. Under lower concentration of salt stress, the Q B-non-reductive PSⅡ reaction centers formed at the beginning of photoinhibition could be effectively used to compose active PSⅡ reaction center (RC) and repair the reversible inactivated PSⅡ RC. Under higher concentration of salt stress, PSⅡ reaction centers were seriously damaged during photoinhibition, the Q B-non-reductive PSⅡ RC could only be partly effective at the early time of photoinhibition, thus led to the accumulation of Q B-non-reductive PSⅡ RC in the course of restoration under dim light.
基金Project(50874022)supported by the National Natural Science Foundation of China
文摘At the late stage of solidification with ultrasonic treatment (UST) in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification microstructure were investigated in order to better study the mechanism of UST. It is considered that the overflowing phenomenon occurs due to the changes of vibration and flow in the remaining semisolid. Because the overflowed portion comes from the region with intense UST effect and vibrates with the probe during solidification, great modification of primary and euteetic Si (about 10 pm in length) and refinement of primary a(Al) (about 70 μm in size) are observed in this portion.
基金Project(51074031)supported by the National Natural Science Foundation of ChinaProject supported by the Korea National Project
文摘In order to improve the quality of clad ingots, diverse physical fields including electromagnetic stirring, power ultrasonic and compound field of ultrasonic and electromagnetic stirring were attempted to prepare clad ingots of 3003/4004 alloys. The solidification structures near the interface in clad ingots were investigated. The experiment results indicate that the solidification structure of 4004 alloy changes from dendritic crystals to petal-like grains when the clad ingot is treated by electromagnetic stirring. With the effect of power ultrasonic, the solidified microstructure of 4004 alloy exhibits the refinement of both primary a(A1) and eutectic silicon. Under the compound field, the primary a(A1) is refined, the morphology of eutectic silicon has a transition from a coarse plate-like form without treatment or thin acicular-like form with power ultrasonic to fine coral-like form.
文摘The interaction between the active chips mounted and the same base plate is considered as a thermoelectrical coupling effect.An approach to coupling effect analysis of a multi-chip system is presented with IGBT as a sample.Finite element method is used to evaluate the temperature distribution in power modules.The precise electrothermal model is obtained by fitting the curve of transient thermal impedance with a finite series of exponential terms,in which,the thermal-coupling effect among chips is considered as a prediction of the highest transient temperature of the chips.This model can be used in many thermal monitoring systems.Both ANSYS and PSPICE si- mulation software have been employed,and the simulation results agree with the experimental ones very well.
文摘A power amplifier MIC with power combining based on AlGaN/GaN HEMTs was fabricated and measured. The amplifier consists of four 10 × 120μm transistors. A Wilkinson splitters and combining were used to divide and combine the power. By biasing the amplifier at VDS = 40V, IDS = 0.9A, a maximum CW output power of 41.4dBm with a maximum power added efficiency (PAE) of 32.54% and a power combine efficiency of 69% was achieved at 5.4GHz.