Impact of Intrinsic Muscle Weakness on Muscle–Bone Crosstalk in Osteogenesis Imperfecta

Bone and muscle are highly synergistic tissues that communicate extensively via mechanotransduction and biochemical signaling. Osteogenesis imperfecta (OI) is a heritable connective tissue disorder of severe bone fragility and recently recognized skeletal muscle weakness. The presence of impaired bone and muscle in OI leads to a continuous cycle of altered muscle–bone crosstalk with weak muscles further compromising bone and vice versa. Currently, there is no cure for OI and understanding the pathogenesis of the skeletal muscle weakness in relation to the bone pathogenesis of OI in light of the critical role of muscle–bone crosstalk is essential to developing and identifying novel therapeutic targets and strategies for OI. This review will highlight how impaired skeletal muscle function contributes to the pathophysiology of OI and how this phenomenon further perpetuates bone fragility.     

不闭合全光纤电流互感器相间磁场干扰特性

针对全光纤电流互感器(FOCT)传感环不闭合易受相间磁场干扰的问题进行了研究,并提出了一种提高不闭合FOCT抗相间磁场干扰能力的新方法。建立了不闭合FOCT相间磁场干扰数学模型,通过理论研究和仿真分析得出传感环不闭合度、传感环半径、传感环缠绕匝数和相间距离是构成相间磁场干扰特性的主要因素,且总有两个最佳方位角,使得相间磁场不会干扰本相FOCT准确度。据此提出了一种最佳方位角优化方法,即通过将FOCT摆放到最佳方位角,来提高抗相间磁场干扰的能力。实验结果与理论分析相一致,并验证了所提方法的正确性。通过该方法,相间磁场干扰引起的误差由-0.27%下降到-0.02%,使不闭合FOCT满足0.2级要求。     

Sensor interpixel correlation analysis and reduction for color filter array high dynamic range image reconstruction

High dynamic range imaging (HDRI) by bracketing of low dynamic range (LDR) images is demanding, as the sensor is deliberately operated at saturation. This exacerbates any crosstalk, interpixel capacitance, blooming and smear, all causing interpixel correlations (IC) and a deteriorated modulation transfer function (MTF). Established HDRI algorithms exclude saturated pixels, but generally overlook IC. This work presents a calibration method to estimate the affected region from saturated pixels for a color filter array (CFA) sensor, using the native CFA as a matched filter. The method minimizes color crosstalk given a set of candidates for proximity regions, and requires no special setup. Results are shown for a 21‐bit HDR output image with improved color fidelity and reduced noise. The calibration reduces IC in the LDR images and is performed only once for a given sensor. The improvement is applicable to any HDRI algorithm based on CFA image bracketing, irrespective of sensor technology. Generalizations to subsaturated and supersaturated pixels are described, facilitating a suggested irradiance‐exposure dependent point spread function charge repatriation strategy.     

串道现象对测量结果的影响

为更加准确地评价低水平放射性样品的测量结果,利用低本底α/β测量仪研究了串道现象对测量结果的影响及其影响程度。利用239Pu和90Sr-90 Y电镀源测定了α通道与β通道之间的串道因子,结果表明:α通道对β通道的串道现象明显,在样品测量时应考虑扣除串道带来的计数;β通道对α通道的串道影响很小,但在β净计数率足够高时,仍会对α的测量结果带来明显影响。样品测量过程中,考虑到不同α核素导致的串道因子之间的差异,为避免单一核素刻度串道因子引入新的误差,使用合适的遮挡物完全屏蔽样品中的α射线,可确保测量结果更加准确。     

蛇形防护布线设计

高速电路中蛇形线可作为传统防护布线的替代方案，但其提出过程未曾考虑如何进行合理的设计。文中基于蛇形防护布线的外形特征影响耦合参数的原理，通过全波求解器建立蛇形防护布线模型，分析了其端接策略以及特征变化对应的远端串扰变化规律，得出了蛇形防护布线的合理设计方法。结果表明，短路策略作为最佳策略，且在信号边沿变化较快的情况下，应采用线宽小、高度高和长度短的蛇形线作为防护布线。     

A magnetic field simulating device for current measuring instruments testing purpose

In this paper, it presented a device intended to reproduce magnetic fields of differents shapes to help the test or calibration of current measuring instruments based on Ampere's Law (current transformers, current clamps, and Rogowsky probes). In particular, this device can reproduce the effect of uncentered currents without requiring any mechanical displacement of the conductor or the device under test during its operation. Any uncentered or distributed current is approximated by a linear combination of currents flowing along a specific set of conductors. First, the theoretical vectorial analysis is presented, and second, a specific arrangement of conductors is used to illustrate the method. A number of measurements have been taken to check the results. Copyright © 2014 John Wiley & Sons, Ltd.     

非均匀传输线间的串扰研究

应用时域有限差分法对非均匀传输线间的串扰耦合进行分析。基于细线散射的时域有限差分法分析非均匀结构时,采用阶梯式均匀传输线模型,对非均匀传输线进行分段逼近。针对不等长、线径变化、非平行线和交叉线4种情况分析其参数变化对串扰的影响。研究表明：不等长电缆超出部分长度对串扰耦合幅度影响较小,对谐振频率影响较大;电缆线径的变化对其串扰耦合影响较小;非平行线和交叉线的角度对电缆间串扰的影响较大。     

超深亚微米工艺下预防串扰方法

随着工艺特征尺寸的不断缩小,芯片的信号完整性问题逐渐恶化。根据超深亚微米(ultra-deep submicron,UDSM)工艺特性,阐述了串扰噪声和同步开关噪声(Simultaneous Switch Noise,SSN)的产生机理以及对芯片信号完整性的影响,并且分析了走线密度、时钟频率和供电布局等与这2类噪声强度相关的主要因素,进而得出了在集成电路版图设计早期,有效预防和抑制信号完整性问题的一系列方法。     

双面硅条探测器的研制与测试

研制了双面硅条探测器。探测器灵敏面积为48mm×48mm,厚约300μm,结面和欧姆面的硅条互相垂直,均由相互平行、宽度相等的48条组成,每条宽0.9mm、间距0.1mm。对其电气特性(耗尽偏压、反向漏电流、条间电阻)和探测特性(上升时间、能量分辨、条间串扰)进行了测试。在偏压为-15V时,各条平均反向漏电流小于10nA。对于从结面入射的5.157 MeV的α粒子,前放信号上升时间约45ns,结面各条的能量分辨率约0.6%~0.7%,基本无条间串扰;欧姆面各条能量分辨率较差,存在条间串扰。