All tissues in the body are subjected externally to gravity and internally by collagenfibril and cellular retractive forces that create stress and energy equilibrium required for homeostasis.Mechanotransduction involve...All tissues in the body are subjected externally to gravity and internally by collagenfibril and cellular retractive forces that create stress and energy equilibrium required for homeostasis.Mechanotransduction involves mechanical work(force through a distance)and energy storage as kinetic and potential energy.This leads to changes in cell mitosis or apoptosis and the synthesis or loss of tissue components.It involves the application of energy directly to cells through integrin-mediated processes,cell-cell connections,stretching of the cell cytoplasm,and activation of the cell nucleus via yes-associated protein(YAP)and transcriptional coactivator with PDZ-motif(TAZ).These processes involve numerous complexes,intermediate molecules,and multiple pathways.Several pathways have been identified from research studies on vertebrate cell culture and from studies in invertebrates.These pathways involve mechanosensors and other molecules that activate the pathways.This review discusses the mitogen-activated protein kinase(MAPK)family,Hippo,Hedgehog,and Wingless-related integration site(WNT)/βcatenin signaling pathways.The mediators covered includeβcatenin,ion channels,growth factors,hormone receptors,members of the Ras superfamily,and components of the linker of nucleoskeleton and cytoskeleton(LINC)complex.However,the interrelationship among the different pathways remains to be clarified.Integrin-mediated mechanotransduction involves direct tensile loading and energy applied to the cell membrane via collagenfibril stretching.This energy is transferred between cells by stretching the cell-cell connections involving cadherins and the WNT/βcatenin pathway.These alterations induce changes in intracellular events in the cytoskeleton and nuclear skeleton caused by the release of YAP and TAZ.These coactivators then penetrate through the nuclear pores and influence nuclear cell function.Alteration in the balance of forces and energy applied to cells and tissues is hypothesized to shift the cell-extracellular matrix mechani展开更多
LINC(Linear Amplifier Using Nonlinear Components)技术是使用非线性的功放来实现信号的线性放大。LINC技术克服了传统线性化技术的效率低,带宽窄的问题,理想情况下能够达到100%的效率。信号分离是LINC的关键技术,信号分离的特性严重...LINC(Linear Amplifier Using Nonlinear Components)技术是使用非线性的功放来实现信号的线性放大。LINC技术克服了传统线性化技术的效率低,带宽窄的问题,理想情况下能够达到100%的效率。信号分离是LINC的关键技术,信号分离的特性严重影响了LINC合成信号的性能。根据LINC技术信号分离原理,采用CORDIC算法来实现输入信号的幅相分离,将输入的调幅调相的变包络信号分离成两路恒包络调相信号。同时采用了一种优化的信号分离算法,把初步分离的两路数据进行角度比较,根据选择最小夹角原则重新分配两路数据,达到改进信号包络的目的。对信号分离过程进行仿真验证,表明信号的恒包络特点得到了显著改善,最后使用FPGA实现。展开更多
The nuclear envelope comprises the outer nuclear membrane,inner nuclear membrane(INM),and nucleopore.Although∼60 INM proteins have been identified,only a few of them have been well characterized,revealing their cruci...The nuclear envelope comprises the outer nuclear membrane,inner nuclear membrane(INM),and nucleopore.Although∼60 INM proteins have been identified,only a few of them have been well characterized,revealing their crucial roles.Our group focused on the INM protein transmembrane protein 201(TMEM201),whose role in cellular function remains to be defined.In this study,we investigated the role of TMEM201 in endothelial cell migration and angiogenesis.Depletion of TMEM201 expression by short hairpin RNA-mediated interference impeded human umbilical vein endothelial cell(HUVEC)angiogenic behavior in tube formation and fibrin gel bead sprouting assays.Meanwhile,TMEM201-deficient HUVECs exhibited impaired migration ability.We next explored the underlying mechanism and found that the N-terminal of TMEM201 interacted with the linker of nucleoskeleton and cytoskeleton complex and was required for regulating endothelial cell migration and angiogenesis.These in vitro findings were further confirmed by using in vivo models.In Tmem201-knockout mice,retinal vessel development was arrested and aortic ring sprouting was defective.In addition,loss of tmem201 impaired zebrafish intersegmental vessel development.In summary,TMEM201 was shown to regulate endothelial cell migration and control the process of angiogenesis.This study is the first to reveal the role of INM proteins in the vascular system and angiogenesis.展开更多
In order to overcome the bottleneck of low linearity and low resolution, an improved delay line structure is proposed with a calibration algorithm to conquer PVT （process, voltage and temperature） variations for an ...In order to overcome the bottleneck of low linearity and low resolution, an improved delay line structure is proposed with a calibration algorithm to conquer PVT （process, voltage and temperature） variations for an all- digital design. The chip is implemented in 0.13 μm CMOS technology. Measurement results show that the proposed structure with the calibration algorithm can evidently improve the linearity and resolution of the delay line. The delay resolution is 2 ps and the root mean square jitter of the delay is 4.71 ps, leading to an error vector magnitude enhancement of 1.32 dB.展开更多
The linear amplification with nonlinear component transmitter is a promising solution to high efficiency and high linearity amplification for non-constant envelope signals. An all-digital synthesizable baseband for a ...The linear amplification with nonlinear component transmitter is a promising solution to high efficiency and high linearity amplification for non-constant envelope signals. An all-digital synthesizable baseband for a delay-based LINC transmitter is implemented. This paper proposes a standard-cell based synthesizable methodology which can be applied in the ASIC process efficiently without performance degradation compared to the manual layout. A scheme to overcome the limited resolution of conventional phase detectors is proposed. It employs alter- native phase detector structures to provide reconfigurability for higher resolution after fabricating, resulting in an 11 ps resolution improvement. Due to the PVT variation, an adaptive calibration scheme focusing on the inherent imbalance between two delay lines is depicted, which reveals an effective EVM enhancement of 5.37 dB. This baseband chip is implemented in 0.13 μm CMOS technology, and the transmitter with the baseband has an EVM of-28.96 dB and an ACPR of-29.51 dB, meeting the design requirement.展开更多
文摘All tissues in the body are subjected externally to gravity and internally by collagenfibril and cellular retractive forces that create stress and energy equilibrium required for homeostasis.Mechanotransduction involves mechanical work(force through a distance)and energy storage as kinetic and potential energy.This leads to changes in cell mitosis or apoptosis and the synthesis or loss of tissue components.It involves the application of energy directly to cells through integrin-mediated processes,cell-cell connections,stretching of the cell cytoplasm,and activation of the cell nucleus via yes-associated protein(YAP)and transcriptional coactivator with PDZ-motif(TAZ).These processes involve numerous complexes,intermediate molecules,and multiple pathways.Several pathways have been identified from research studies on vertebrate cell culture and from studies in invertebrates.These pathways involve mechanosensors and other molecules that activate the pathways.This review discusses the mitogen-activated protein kinase(MAPK)family,Hippo,Hedgehog,and Wingless-related integration site(WNT)/βcatenin signaling pathways.The mediators covered includeβcatenin,ion channels,growth factors,hormone receptors,members of the Ras superfamily,and components of the linker of nucleoskeleton and cytoskeleton(LINC)complex.However,the interrelationship among the different pathways remains to be clarified.Integrin-mediated mechanotransduction involves direct tensile loading and energy applied to the cell membrane via collagenfibril stretching.This energy is transferred between cells by stretching the cell-cell connections involving cadherins and the WNT/βcatenin pathway.These alterations induce changes in intracellular events in the cytoskeleton and nuclear skeleton caused by the release of YAP and TAZ.These coactivators then penetrate through the nuclear pores and influence nuclear cell function.Alteration in the balance of forces and energy applied to cells and tissues is hypothesized to shift the cell-extracellular matrix mechani
文摘LINC(Linear Amplifier Using Nonlinear Components)技术是使用非线性的功放来实现信号的线性放大。LINC技术克服了传统线性化技术的效率低,带宽窄的问题,理想情况下能够达到100%的效率。信号分离是LINC的关键技术,信号分离的特性严重影响了LINC合成信号的性能。根据LINC技术信号分离原理,采用CORDIC算法来实现输入信号的幅相分离,将输入的调幅调相的变包络信号分离成两路恒包络调相信号。同时采用了一种优化的信号分离算法,把初步分离的两路数据进行角度比较,根据选择最小夹角原则重新分配两路数据,达到改进信号包络的目的。对信号分离过程进行仿真验证,表明信号的恒包络特点得到了显著改善,最后使用FPGA实现。
基金supported by the National Natural Science Foundation of China(31871414 and 81971265)Science and Technology Commission of Shanghai Municipality(19JC1416300)+1 种基金Shanghai Institute of Materia Medica(SIMM010203)the Lingang Laboratory(LG202103-03-04).
文摘The nuclear envelope comprises the outer nuclear membrane,inner nuclear membrane(INM),and nucleopore.Although∼60 INM proteins have been identified,only a few of them have been well characterized,revealing their crucial roles.Our group focused on the INM protein transmembrane protein 201(TMEM201),whose role in cellular function remains to be defined.In this study,we investigated the role of TMEM201 in endothelial cell migration and angiogenesis.Depletion of TMEM201 expression by short hairpin RNA-mediated interference impeded human umbilical vein endothelial cell(HUVEC)angiogenic behavior in tube formation and fibrin gel bead sprouting assays.Meanwhile,TMEM201-deficient HUVECs exhibited impaired migration ability.We next explored the underlying mechanism and found that the N-terminal of TMEM201 interacted with the linker of nucleoskeleton and cytoskeleton complex and was required for regulating endothelial cell migration and angiogenesis.These in vitro findings were further confirmed by using in vivo models.In Tmem201-knockout mice,retinal vessel development was arrested and aortic ring sprouting was defective.In addition,loss of tmem201 impaired zebrafish intersegmental vessel development.In summary,TMEM201 was shown to regulate endothelial cell migration and control the process of angiogenesis.This study is the first to reveal the role of INM proteins in the vascular system and angiogenesis.
文摘In order to overcome the bottleneck of low linearity and low resolution, an improved delay line structure is proposed with a calibration algorithm to conquer PVT （process, voltage and temperature） variations for an all- digital design. The chip is implemented in 0.13 μm CMOS technology. Measurement results show that the proposed structure with the calibration algorithm can evidently improve the linearity and resolution of the delay line. The delay resolution is 2 ps and the root mean square jitter of the delay is 4.71 ps, leading to an error vector magnitude enhancement of 1.32 dB.
文摘The linear amplification with nonlinear component transmitter is a promising solution to high efficiency and high linearity amplification for non-constant envelope signals. An all-digital synthesizable baseband for a delay-based LINC transmitter is implemented. This paper proposes a standard-cell based synthesizable methodology which can be applied in the ASIC process efficiently without performance degradation compared to the manual layout. A scheme to overcome the limited resolution of conventional phase detectors is proposed. It employs alter- native phase detector structures to provide reconfigurability for higher resolution after fabricating, resulting in an 11 ps resolution improvement. Due to the PVT variation, an adaptive calibration scheme focusing on the inherent imbalance between two delay lines is depicted, which reveals an effective EVM enhancement of 5.37 dB. This baseband chip is implemented in 0.13 μm CMOS technology, and the transmitter with the baseband has an EVM of-28.96 dB and an ACPR of-29.51 dB, meeting the design requirement.
