High-Power Raman Soliton Generation at 1.7 μm in All-Fiber Polarization-Maintaining Erbium-Doped Amplifier

An all-fiber polarization maintaining high-power laser system operating at 1.7 μm based on the Ramaninduced soliton self-frequency shifting effect is demonstrated. The entirely fiberized system is built by erbiumdoped oscillator and two-stage amplifiers with polarization maintaining commercial silica fibers and devices, which can provide robust and stable soliton generation. High-power soliton laser with the average power of 0.28 W,the repetition rate of 42.7 MHz, and pulse duration of 515 fs is generated directly from the main amplifier.Our experiment provides a feasible method for high-power all-fiber polarization maintaining femtosecond laser generation working at 1.7 μm.

Broadband Dual-Input Doherty Power Amplifier Design Based on a Simple Adaptive Power Dividing Ratio Function

In this paper,a simple adaptive power dividing function for the design of a dual-input Doherty power amplifier(DPA)is presented.In the presented approaches,the signal separation function(SSF)at different frequency points can be characterized by a polynomial.And in the practical test,the coefficients of SSF can be determined by measuring a small number of data points of input power.Same as other dualinput DPAs,the proposed approach can also achieve high output power and back-off efficiency in a broadband operation band by adjusting the power distribution ratio flexibly.Finally,a 1.5-2.5 GHz highefficiency dual-input Doherty power amplifier is implemented according to this approach.The test results show that the peak power is 48.6-49.7d Bm,and the 6-d B back-off efficiency is 51.0-67.0%,and the saturation efficiency is 52.4-74.6%.The digital predistortion correction is carried out at the frequency points of 1.8/2.1GHz,and the adjacent channel power ratio is lower than-54.5d Bc.Simulation and experiment results can verify the effectiveness and correctness of the proposed method.

Harmonic balance simulation of the influence of component uniformity and reliability on the performance of a Josephson traveling wave parametric amplifier

A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A typical JTWPA consists of thousands of Josephson junctions connected in series to form a transmission line and hundreds of shunt LC resonators periodically loaded along the line for phase matching.Because the variation of these capacitors and inductors can be detrimental to their high-frequency characteristics,the fabrication of a JTWPA typically necessitates precise processing equipment.To guide the fabrication process and further improve the design for manufacturability,it is necessary to understand how each electronic component affects the amplifier.In this paper,we use the harmonic balance method to conduct a comprehensive study on the impact of nonuniformity and fabrication yield of the electronic components on the performance of a JTWPA.The results provide insightful and scientific guidance for device design and fabrication processes.

Three-channel CMOS transimpedance amplifier for LiDAR sensor receiver

For time-of-flight(TOF)light detection and ranging(LiDAR),a three-channel high-performance transimpedance amplifier(TIA)with high immunity to input load capacitance is presented.A regulated cascade(RGC)as the input stage is at the core of the complementary metal oxide semiconductor(CMOS)circuit chip,giving it more immunity to input photodiode detectors.A simple smart output interface acting as a feedback structure,which is rarely found in other designs,reduces the chip size and power consumption simultaneously.The circuit is designed using a 0.5μm CMOS process technology to achieve low cost.The device delivers a 33.87 dB?transimpedance gain at 350 MHz.With a higher input load capacitance,it shows a-3 dB bandwidth of 461 MHz,indicating a better detector tolerance at the front end of the system.Under a 3.3 V supply voltage,the device consumes 5.2 mW,and the total chip area with three channels is 402.8×597.0μm2(including the test pads).

3D打印个性化截骨导板辅助TKA应用效果的Meta分析

膝关节骨关节炎(KOA)是一种好发于中老年人群的慢性劳损性骨关节病,进展到晚期时,主要行全膝关节置换术(TKA)治疗。但该手术操作过程复杂,难度大,术后有不少患者出现严重并发症以及手术失败情况的发生[1]。3D打印的个性化截骨导板是根据术前CT或MRI的膝关节影像学资料对患者特定患处的解剖结构进行个性化设计定制的,有研究显示能够提高患肢关节各部件的准确性,减少手术时间和降低成本[2-3]。

刘氏正骨手法对TKA术后功能康复的疗效研究

探讨刘氏正骨手法对全膝关节置换术后功能康复的疗效研究,并作对比分析。方法 选用我院关节骨科2019年6月—2022年12月原发性单侧膝关节骨性关节炎患者68例,均行人工全膝关节置换术(TKA)治疗,随机分为两组进行比较,治疗组采用刘氏正骨手法加功能锻炼进行康复,对照组单纯行功能锻炼促进康复,采用AKS膝关节功能评分系统,评价两组术后一个疗程康复治疗后关节功能恢复情况。结果 刘氏正骨手法治疗组的有效率为97%,改善率为46.5%;单纯功能锻炼对照组的有效率为87.9%,改善率为39.3%,刘氏正骨手法治疗组的有效率及改善率均明显高于对照组,差异均有统计学意义(P<0.05)。结论 刘氏正骨手法在TKA术后功能康复锻炼方面效果较好,可以起到减少疼痛,明显改善关节屈伸不利和肌肉萎缩无力的状态,缩短了患者术后功能康复周期,达到了快速康复(ERAS)的治疗目的。

5G Wideband Bandpass Filtering Power Amplifiers Based on a Bandwidth-Extended Bandpass Matching Network

In this paper,a 5G wideband power amplifier(PA)with bandpass filtering response is synthesized using a bandwidth-extended bandpass filter as the matching network(MN).In this structure,the bandwidth(θ_(C))is defined as a variable in the closedform equations provided by the microstrip bandpass filter.It can be extended over a wide range only by changing the characteristic impedances of the structure.Different from the other wideband MNs,the extension of bandwidth does not increase the complexity of the structure(order n is fixed).In addition,based on the bandwidth-extended structure,the wideband design of bandpass filtering PA is not limited to the fixed bandwidth of the specific filter structure.The theoretical analysis of the MN and the design flow of the PA are provided in this design.The fabricated bandpass filtering PA can support almost one-octave bandwidth(2-3.8 GHz),covering the two 5G bands(n41 and n78).The drain efficiency of 47%-60%and output power higher than 40 dBm are measured.Good frequency selectivity in S-parameter measurements can be observed.

Design and performance of a high-speed and low-noise preamplifier for SiPM

Considering the R&D for upgrading the K^(0)_(L) andμdetectors in the Belle II experiment using a scintillator and silicon pho-tomultiplier(SiPM),we designed a compact high-speed and low-noise preamplifier.The preamplifier demonstrated a good gain stability,bandwidth of 426 MHz,baseline noise level ofσ≈0.6 mV,dynamic range of up to170 mV of the input signal amplitude,good time resolution of 20 ps,and it can be comprehensively applied to SiPMs.Adopting pole-zero-cancelation in the preamplifier reduces both the rise and fall times of the SiPM signal,which can significantly improve the time resolution and reduce the pile-up when using a large SiPM or an array of SiPMs.Various combinations of the preamplifier and several types of SiPMs demonstrated time resolutions better than 50 ps for most cases;when the number of detected photons was larger than 60,a time resolution of approximately 25 ps was achieved.

ERAS外科管理模式在西藏地区单侧TKA围手术期中的应用

目的探讨加速康复外科(ERAS)管理模式在单侧全膝关节置换术(TKA)围手术期中的应用。方法选取2018年01月~2018年06月收治的行TKA患者40例,采用(ERAS)管理模式定为(ERAS组),将2017年1月~2017年12月收治的行TKA患者40例,采用传统的管理模式定为(非ERAS组)。比较两组术后3天、1周、1月、1年的关节功能恢复功能及患者对手术效果的满意度。结果术后3天、1周、1月,视觉模拟疼痛评分(VAS)评分:ERAS组低于非ERAS组,差异具有统计学意义(P<0.05);术后膝关节评分(HSS)和膝关节活动度(ROM):ERAS组均高于非ERAS组(P<0.05);出院1月后对手术效果满意度:非常满意的百分比ERAS组为(86%),非ERAS组(73%),两组差异(p<0.052);随访1年,两组VAS、HSS、ROM结果无明显差异。结论TKA患者在ERAS管理模式下能够明显改善和提高膝关节术后早期功能(1月内),加速术后康复,提高患者对手术效果的满意度。

UKA与TKA治疗膝单间室骨关节炎的临床对比研究

目的:探讨单踝置换术(UKA)与全膝关节置换术(TKA)治疗膝单间室骨关节炎的早期临床效果。方法:选择玉山县中医院2018年4月-2020年4月收治的膝单间室骨关节炎患者88例进行研究,针对不同的手术操作方法进行分组,分为UKA组(n=45)与TKA组(n=43)。对比两组围手术期临床指标,两组术后1、3、6个月的膝关节协会评分(KSS)、牛津膝关节评分(oxford knee score,OKS)、膝关节活动度(ROM)。结果:UKA组术后3 d视觉模拟评分法(VAS)评分、术后1 d血红蛋白(Hb)下降比均较TKA组低,手术时间、住院天数均较TKA组短,差异均有统计学意义(P<0.05)。术后3、6个月,UKA组KSS临床、功能评分均高于TKA组,OKS评分均低于TKA组,ROM均高于TKA组,差异均有统计学意义(P<0.05)。结论:无论是UKA还是TKA治疗膝单间室骨关节炎均可获得较好的临床效果,但UKA在围手术期临床指标上可表现出更高的优势,能够对膝关节功能及活动度的恢复起到较强的促进作用。

Impact of amplified spontaneous emission noise on the SRS threshold of high-power fiber amplifiers

Impact of amplified spontaneous emission(ASE)noise on the stimulated Raman scattering(SRS)threshold of highpower fiber amplifiers is demonstrated numerically through a spectral evolution approach.The simulation results confirm that ASE noise in the Raman wavelength band could reduce the SRS threshold of high-power fiber amplifiers significantly.As for ASE noise originated the main amplifier,it becomes stronger and reduces the SRS threshold at shorter operation wavelength below 1052 nm.As for ASE noise originated from the seed laser,it reduces the SRS threshold at different operation wavelength under the condition that the Raman ratio is over-90 dB in the seed laser.The theoretical method and results in this work could provide a well reference to extend the operation wavelength of high-power fiber lasers.

Improving source-in-the-middle continuous-variable quantum key distribution using a heralded hybrid linear amplifier

A hybrid linear amplifier is inserted at the output of the source-in-the-middle distribution protocol to overcome the shortcomings of the transmission distance.The modified protocol aims to maintain a high key rate for long-distance transmission under high noise.It has the potential to significantly broaden the application range of the continuous variable quantum key distribution protocol.The effects of amplifier parameters and noise on the modified protocol are analyzed in detail with regard to applying it to a practical system.To make the simulation more realistic,the effect of finite size on the new protocol is taken into account.It will serve as a guideline for the future use of hybrid linear amplifiers.Different parameters can be adjusted to achieve the best performance for key rates of different quantum channels.

Piezomagnetic vibration energy harvester with an amplifier

We study the effect of an amplification mechanism in a nonlinear vibration energy harvesting system where a ferromagnetic beam resonator is attached to the vibration source through an additional linear spring with a damper.The beam moves in the nonlinear double-well potential caused by interaction with two magnets.The piezoelectric patches with electrodes attached to the electrical circuit support mechanical energy transduction into electrical power.The results show that the additional spring can improve energy harvesting.By changing its stiffness,we observed various solutions.At the point of the optimal stiffness of the additional spring,the power output is amplified a few times depending on the excitation amplitude.

Research Towards Terahertz Power Amplifiers in Silicon-Based Process

In view of the existing design challenges for Terahertz(THz)power amplifiers(PAs),the common design methods and the efforts of the State Key Laboratory of Millimeter Wave,Southeast University,China in the development of silicon-based THz PAs,mainly including silicon-based PAs with operating frequencies covering 100–300 GHz,are summarized in this paper.Particularly,we design an LC-balun-based two-stage differential cascode PA with a center frequency of 150 GHz and an output power of 14 dBm.Based on a Marchand balun,we report a 220 GHz three-stage differential cascode PA with a saturated output power of 9.5 dBm.To further increase the output power of THz PA,based on a four-way differential power combining technique,we report a 211–263 GHz dual-LC-tank-based broadband PA with a recorded 14.7 dBm Psat and 16.4 dB peak gain.All the above circuits are designed in a standard 130 nm silicon germanium(SiGe)BiCMOS process.

Vertical vibration control using nonlinear energy sink with inertial amplifier

To reduce additional mass, this work proposes a nonlinear energy sink(NES)with an inertial amplifier(NES-IA) to control the vertical vibration of the objects under harmonic and shock excitations. Moreover, this paper constructs pure nonlinear stiffness without neglecting the gravity effect of the oscillator. Both analytical and numerical methods are used to evaluate the performance of the NES-IA. The research findings indicate that even if the actual mass is 1% of the main oscillator, the NES-IA with proper inertia angles and mass distribution ratios can still effectively attenuate the steady-state and transient responses of the main oscillator. Nonlinear stiffness and damping also have important effects. Due to strongly nonlinear factors, the coupled system may exhibit higher branch responses under harmonic excitation. In shock excitation environment, the NES-IA with a large dynamic mass can trigger energy capture of both main resonance and high-frequency resonance. Furthermore, the comparison with the traditional NES also confirms the advantages of the NES-IA in overcoming mass dependence.

“化瘀利水”法在治疗初次TKA术后肢体肿胀中的应用研究

分析“化瘀利水”法对于初次人工全膝关节置换(TKA)术后并发肢体肿胀的治疗价值。方法 选择2021年10月至2023年3月间入院治疗的100例膝关节骨性关节炎(KOA)初次接受TKA术后患者,均存在肢体肿胀表现。随机数字表分组,试验组50例进行“化瘀利水”法治疗,对照组50例进行常规术后治疗,对比治疗效果。结果 试验组的总有效率高于对照组(P<0.05)。入院时,对比组间的髌骨中点偏下10cm处小腿周径、中医症状分级量化评分、视觉模拟量表(VAS)评分、美国特种外科医院(HSS)评分对比无差异(P>0.05)。术后第1/3/7/14d,试验组的小腿周径小于对照组,中医症状分级量化评分低于对照组,VAS评分低于对照组,HSS评分高于对照组(P<0.05)。结论 “化瘀利水”法能够缓解初次TKA术后患者的肢体肿胀程度,减轻术后痛感,且能缓解相关症状,改善膝关节功能。

阿哌沙班与利伐沙班预防老年糖尿病患者TKA术后VTE的临床对比研究

探究阿哌沙班和利伐沙班防治VTE的效果差异,为临床应用提供理论依据。方法 2021年1月至2022年9月为选定的就诊区间值,从我院骨科收治的膝关节置换术患者中进行筛选,50例患者依据不同的治疗方案完成小组划分,阿哌沙班组与利伐沙班组各25例,对比分析两组患者的深静脉血栓发生率、血液学指标、PT及APTT凝血指标、药物安全性指标、FBG指标的监测等内容。结果 两组在深静脉血栓发生率方面,未呈现明显差异性(P>0.05);两组的D-D血液学指标在变化幅度方面均未呈现明显差异性(P>0.05);相比利伐沙班组,阿哌沙班组具备更强的药物安全性(P<0.05);两组的治疗前后的FBG血糖指标变化情况均未呈现明显差异性(P>0.05)。结论 针对行膝关节置换术的老年糖尿病患者,分别给予阿哌沙班、利伐沙班有效防治VTE,药物阿哌沙班在未对其他身体指标带来负面影响的同时,具备更强的安全性及有效性,具有十分重要的临床应用价值,值得临积极采纳并推广。

光放大器原理及其发展

光通信系统的工作性能,除与光源有关外,还与其传输媒质有关。随着光纤技术的发展,通过追求光通信领域的远距离传输,诞生了光放大器,光放大器可以做到直接放大光信号,在通信领域有很大的应用价值。总结了光放大器的基本原理及其发展。首先介绍了光放大器的概念、分类和原理。然后分别对三类光放大器的关键技术进行了介绍,包括工作原理与性能方面,然后对各类光放大器的国内外现状进行了分析。最后,对光放大器未来的发展进行了展望。

长波段半导体激光泵浦光纤激光器实现2 kW功率输出

半导体激光(LD)泵浦的高功率光纤激光器具有效率高、体积小、重量轻、稳定性好等优点,在工业加工等诸多领域都有着广泛的应用。为了提高泵浦光吸收率,传统光纤激光器常用915 nm和976 nm波段的LD作为激光的泵浦源。在该类LD泵浦的光纤激光器中,由于量子亏损和泵浦吸收系数相对较高,光纤激光器的热致模式不稳定(TMI)阈值相对较低。为了提高量子效率和潜在的TMI阈值,提出采用大于1010 nm波段的LD直接泵浦光纤激光器,产生高量子效率激光。搭建了振荡放大一体化的全光纤激光器,采用总泵浦功率为2.56 kW的1010 nm波段LD泵浦,首次获得输出功率2.05 kW、光束质量M^(2)约1.7的激光。后续将通过进一步增大泵浦功率、优化光纤特性以实现更高功率、更优光束质量的光纤激光输出。

患病异育银鲫中嗜冷黄杆菌的分离鉴定及组织病理学观察

为确定越冬期内江苏多地异育银鲫暴发性死亡的原因,本研究利用高通量测序比较了健康样品和患病样品的微生物群落多样性和结构组成的差异,分析了异育银鲫病害暴发过程中的细菌类型及特性。结果显示,在属水平上,患病样品中黄杆菌属丰度最高。在种水平上,患病样品中嗜冷黄杆菌的丰度最高,分别达到63.01%和61.31%,显著高于健康组的1.55%。根据微生物群落特征分析结果,从患病样品体表的病灶处分离出优势病原菌NJ01,通过细菌形态学、生理生化分析、16S rDNA序列比对确定NJ01菌株为嗜冷黄杆菌。人工感染NJ01菌株14 d后,1.7×10^(6)和1.7×10^(7) CFU/mL两组的死亡率达到100%,感染症状和自然发病症状一致。组织病理学观察发现,病鱼的肌细胞坏死,间质中充满了淋巴细胞;肝脏中细胞溶解坏死,细胞核消融;在脾脏中发现脾细胞散在坏死,伴随着充血的症状;肾小管上皮脱落,肾间质存在大量淋巴细胞。药物敏感实验结果显示,NJ01菌株对头孢西叮、头孢哌酮、庆大霉素和克拉霉素等敏感。研究表明,优势菌NJ01是致病菌,可通过扰乱机体正常的免疫和代谢功能导致疾病的发生。本研究首次报道了嗜冷黄杆菌在异育银鲫中的致病性,这将为大宗淡水鱼“越冬综合征”的药物防治及其致病机理研究提供参考依据。