A NOVEL ALGORITHM FOR SIDE PEAKS SUPPRESSION OF AMBIGUITY FUNCTION FOR PASSIVE RADAR BASED ON CHINESE DTTB SIGNAL

The ambiguity function of Chinese standard Digital Television Terrestrial Broadcasting (DTTB) signals for passive radar contains one main peak and many side peaks. The side peaks may cause the false alarms. The relative positions and the reasons for the side peaks are analyzed and a new algorithm for side peaks suppression is proposed in this paper. The algorithm, in consideration of the characteristics of the structure of the frame, can eliminate the side peaks completely in the valid Doppler observation interval by setting the reference signals to zero at equal intervals. Both the simulative and experimental results show that this algorithm can improve the performance of target detection of the passive radar based on DTTB signal.

Comparative Investigation of Torque-ripple Suppression Control Strategies Based on Torque-sharing Function for Switched Reluctance Motor

Torque ripple is an inherent property of switched reluctance motor(SRM),which seriously affects the control performance and application of the motor.This paper proposes two torque ripple suppression control strategies based on torque-sharing function(TSF).According to the symmetry characteristics of the flux linkage and rotor position curve family,a fourth-order Fourier series is used to fit the SRM flux linkage analytical model.The coefficient of each harmonic term of the flux linkage model is a function related to current,expressed by a sixth-order polynomial.The torque analytical formula can be derived from the flux linkage model.The torque error is calculated via the identified torque model and is compensated through TSF controller in order to reduce torque ripple.The torque model can also be used to establish the torque loop to achieve accurate tracking of the TSF reference torque to reduce torque ripple.Digital simulation was conducted,followed by the implementation on a SRM test bench using a 28335DSP as the master control chip.The experimental results are consistent with the simulation results,and indicate the effectiveness of the proposed schemes.

The Effect of TSH Suppression Therapy on the Efficacy and Immune Function of Postoperative Patients with Thyroid Cancer

Objective:To investigate the efficacy and immune function of thyroid stimulating hormone(TSH)suppression therapy in postoperative thyroid cancer patients.Methods:Sixty thyroid cancer patients admitted from July 2020–July 2022 were recruited and randomly divided into two groups.The control group(30 patients)received hormone replacement therapy,while the study group(30 patients)received TSH suppression therapy.The thyroid function,clinical efficacy,immune function,and tumor markers of the two groups were compared.Results:After treatment,the levels of free triiodothyronine(FT3)and thyroxine(FT4)in both groups increased significantly,while TSH levels decreased significantly.Moreover,the magnitude of change in the study group was greater than that in the control group(P<0.05).The total effective rate in the study group was significantly higher as compared to the control group(P<0.05).After treatment,the levels of CD3+and CD4+cells in both groups of patients increased significantly,with the study group showing significantly higher levels than the control group,whereas the level of CD8+cells decreased significantly,with the study group having lower levels than the control group(P<0.05).After treatment,the levels of Tg and CEA in both groups were significantly lowered as compared to before treatment,and the levels of Tg and CEA in the study group were significantly lower than the control group(P<0.05).Conclusion:TSH suppression therapy in postoperative thyroid cancer patients can improve thyroid function,suppress the levels of tumor markers,and enhance immune function,thereby achieving good clinical outcomes.

Optimization of the Tuned Mass Damper for Chatter Suppression in Turning

The tuned mass damper（TMD） has been successfully applied to the vibration control in machining, while the most widely adopted tuning is equal peaks, which splits the magnitude of the frequency response function（FRF） into equal peaks. However, chatter is a special self-excited problem and a chatter-flee machining is determined by FRF at the cutting zone. A TMD tuning aiming at achieving the maximum chatter stability is studied, and it is formulated as an optimization problem of maximizing the minimum negative real part of FRF. By employing the steepest descend method, the optimum frequency and damping ratio of TMD are obtained, and they are compared against the equal peaks tuning. The advantage of the proposed tuning is demonstrated numerically by comparing the minimum point of the negative real part, and is further verified by damping a flexible mode from the fixture of a turning machine. A TMD is designed and placed on the fixture along the vibration of the target mode after performing modal analysis and mode shape visualization. Both of the above two ttmings are applied to modify the tool point FRF by tuning TMD respectively. Chatter stability chart of the turning shows that the proposed tuning can increase the critical depth of cut 37% more than the equal peaks. Cutting tests with an increasing depth of cut are conducted on the turning machine in order to distinguish the stability limit. The tool vibrations during the machining are compared to validate the simulation results. The proposed damping design and optimization routine are able to further increase the chatter suppression effect.

Suppression of Sup35 amyloid fibril formation by group II chaperonin from <i>Thermoplasma acidophilum</i>

The Group II chaperonin from Thermoplasma acidophilum was added to the in vitro amyloid fibrillation reaction of yeast Sup35NM protein to assess its effects. By measuring the formation of Sup35NM fibrils in real time using the fluorescent dye Thioflavin T, we found that the addition of T. acidophilum-cpn α16, α1, and β1 proteins suppressed fibril formation. Addition of a 0.1 molar-equivalent T. acidophilum-cpn α16 relative to Sup35NM prolonged the initial lag-time of fibril formation and decreased the rate of fibril extension. Addition of 1 or 3 molar-equivalents of T. acidophilum-cpn monomers also produced a similar effect. Delayed addition of these chaperonins after the initial lag phase did not suppress fibril formation. Interestingly, these effects were also observed upon adding only the apical domain segments of α and β-subunits, and we also found that deletion of the helical protrusion in the apical domain of these segments led to an abolishment of the suppression effects. A synthetic peptide whose sequence corresponded to the helical protrusion also displayed a suppression effect, which indicated that archaeal group II chaperonin binds to Sup35NM through the helical protrusion of the apical domain. These findings suggest that group II chaperonin might be actively involved in suppressing amyloid fibril formation, in addition to acting as a protein folding assistant.

DISCRETE BIDIRECTIONAL ASSOCIATIVE MEMORY WITH LEARNING FUNCTION

In this paper we propose a new discrete bidirectional associative memory (DBAM) which is derived from our previous continuous linear bidirectional associative memory (LBAM). The DBAM performs bidirectionally the optimal associative mapping proposed by Kohonen. Like LBAM and NBAM proposed by one of the present authors,the present BAM ensures the guaranteed recall of all stored patterns,and possesses far higher capacity compared with other existing BAMs,and like NBAM, has the strong ability to suppress the noise occurring in the output patterns and therefore reduce largely the spurious patterns. The derivation of DBAM is given and the stability of DBAM is proved. We also derive a learning algorithm for DBAM,which has iterative form and make the network learn new patterns easily. Compared with NBAM the present BAM can be easily implemented by software.

Vibration suppression for rotating space slender flexible structures based on novel deformation description and NNSMC controller with hyperbolic tangent function

Rotating Space Slender Flexible Structures(RSSFS)are extensively utilized in space operations because of their light weight,mobility,and low energy consumption.To realize the accurate space operation of the RSSFS,it is necessary to establish a precise mechanical model and develop a control algorithm with high precision.However,with the application of traditional control strategies,the RSSFS often suffers from the chattering phenomenon,which will aggravate structure vibration.In this paper,novel deformation description is put forward to balance modeling accuracy and computational efficiency of the RSSFS,which is better appropriate for real-time control.Besides,the Neural Network Sliding Mode Control(NNSMC)strategy modified by the hyperbolic tangent(tanh)function is put forward to compensate for modeling errors and reduce the chattering phenomenon,thereby improving the trajectory tracking accuracy of the RSSFS.Firstly,a mathematical model for the RSSFS is developed according to the novel deformation description and the vibration theory of flexible structure.Comparison of the deformation accuracy between different models proves that the novel modeling method proposed has high modeling accuracy.Next,the universal approximation property of the Radial Basis Function(RBF)neural network is put forward to determine and compensate for modeling errors,which consist of higher-order modes and the uncertainties of external disturbances.In addition,the tanh function is proposed as the reaching law in the conventional NNSMC strategy to suppress driving torque oscillation.The control law of modified NNSMC strategy and the adaptive law of weight coefficients are developed according to the Lyapunov theorem to guarantee the RSSFS stability.Finally,the simulation and physical experimental tests of the RSSFS with different control strategies are conducted.Experimental results show that the control law according to the novel deformation description and the modified NNSMC strategy can obtain accurate tracking of the rotation and reduce the vibration of the RSSFS simultaneously.

Muscle function, physical performance and body composition changes in men with prostate cancer undergoing androgen deprivation therapy

Prostate cancer （PCa） is the most common visceral malignancy in men with androgen deprivation therapy （ADT） the preferred therapy to suppress testosterone production and hence tumor growth. Despite its effectiveness in lowering testosterone, ADT is associated with side effects including loss of muscle mass, diminished muscle strength, decrements in physical performance, earlier fatigue and declining quality of life. This review reports a survey of the literature with a focus on changes in muscle strength, physical function and body composition, due to short-term and long-term ADT. Studies in these areas are sparse, especially well-controlled, prospective randomized trials. Cross-sectional and longitudinal data （up to 2 years） for men with PCa treated with ADT as well as patients with PCa not receiving ADT and age-matched healthy men are presented when available. Based on limited longitudinal data, the adverse effects of ADT on muscle function, physical performance and body composition occur shortly after the onset of ADT and tend to persist and worsen over time. Exercise training is a safe and effective intervention for mitigating these changes and initial guidelines for exercise program design for men with PCa have been published by the American College of Sports Medicine. Disparities in study duration, types of studies and other patient-specific variables such as time since diagnosis, cancer stage and comorbidities may all affect an understanding of the influence of ADT on health, physical performance and mortality.

Sexual Function in Men with Castrate Levels of Testosterone: Observations of a Subgroup of Sexually Active Men with Prostate Cancer Undergoing Androgen Deprivation Therapy

Purpose: To identify possible factors that influence sexual function in men undergoing maximal androgen deprivation therapy (ADT). Patients and Methods: A descriptive exploration was performed looking at characteristics of twenty-two men reporting sexual activity after nine months of maximal ADT. This previously published Phase II study, involved 250 prostate cancer patients undergoing intermittent ADT. An analysis between this cohort and the group that did not maintain sexual function was performed to ascertain if age, testosterone level, functional status or maintenance of quadriceps strength had an impact upon sexual function. Results: There was no difference in age, testosterone level or ECOG performance status between the sexually active and non-sexually active groups. Over the course of 9 months of ADT, the sexually active group appeared to maintain quadriceps muscle strength as measured with physical stands, and maintained overall health as measured by quality of life questionaries, compared to the non-sexually active group. Conclusions: This retrospective study suggests that exercise during ADT may reduce the impact of ADT on sexual function. This warrants further testing, and could be the focus of future randomised controlled trials.

基于双重约束的并网逆变器电流自动化控制方法研究

为降低并网逆变器逆变的并网电流畸变率,提出基于双重约束的并网逆变器电流自动化控制方法。以典型的三相LCL并网逆变器为例,分析其运行状态;并确定并网逆变器在进行逆变转换时,谐波对于逆变器并网电流的影响,计算并网逆变器环路增益函数;采用输出电流直接前馈的改进阻尼控制方法实现电流自动化控制,并引入全局-局部稳定双重约束原则,确定最佳的谐振抑制参数,提升电流的控制效果。测试结果显示,该方法的并网逆变器的电流畸变率均低于5%,电流跳变过程中,可在0.2 s内有效控制跳变电流结果。

中国早期乳腺癌卵巢功能抑制临床应用专家共识(2024年版)

中国乳腺癌患者发病年龄较轻,60%的女性患者在诊断时为绝经前。与绝经后相比,未绝经女性卵巢功能旺盛,可持续大量分泌雌激素、促进乳腺癌细胞增殖。卵巢功能抑制(ovarian function suppression,OFS)已用于乳腺癌临床治疗数十年,大量循证证据表明,单用OFS和加用OFS均可降低未绝经女性乳腺癌的复发风险并改善生存。部分OFS研究的长期随访数据(SOFT/TEXT研究12和13年随访、STO-5研究20年随访、亚裔人群的ASTRRA研究8年随访)近期陆续公布,进一步证实对于早期乳腺癌患者加用OFS可显著降低10年以上的复发风险,提高治愈可能。monarchE和NATALEE研究显示,部分CDK4/6抑制剂叠加在绝经前早期乳腺癌患者含有药物去势[促性腺激素释放激素类似物(gonadotropin releasing hormone analog,GnRHa)]的辅助内分泌治疗方案时仍可进一步增加生存获益。中国抗癌协会乳腺癌专业委员会召集了国内乳腺癌治疗领域的临床专家,在2021年版的基础上共同商讨编制了《中国早期乳腺癌卵巢功能抑制临床应用专家共识(2024年版)》。本共识建议,GnRHa仍作为绝经前激素受体阳性早期乳腺癌OFS方式的首选。GnRHa联合内分泌治疗基础上添加特定CDK4/6抑制剂的激素受体阳性绝经前乳腺癌获益人群包括:淋巴结阳性,淋巴结阴性且满足任一条件[G3,G2伴Ki-67增殖指数≥20%,G2伴多基因检测(21基因评分、Prosigna PAM50、MammaPrint、EndoPredict)高危]。本共识也认可将2023年St.Gallen共识中有化疗指征的风险因素作为OFS适用判定标准之一。GnRHa用药推荐根据激素受体阳性乳腺癌患者化疗前的卵巢功能状态进行决策。如果考虑卵巢保护,推荐GnRHa同步化疗,不影响患者生存获益;如果不考虑卵巢保护,GnRHa同步化疗和GnRHa在化疗结束后序贯使用均被认可,后者更为推荐。围绝经期患者的内分泌治疗建议参照绝经前方案。GnRHa辅助内分泌治疗的时长建议为5年。中高危患者完成5年联合GnRHa的内分泌治疗后,如果未绝经且耐受性良好,可考虑继续2~5年联合GnRHa的内分泌治疗或单用2~5年选择性雌激素受体调节剂(selective estrogen receptor modulator,SERM)治疗。辅助治疗方案中添加GnRHa安全可耐受,推荐应用前和患者充分沟通药物的使用方法和可能的不良事件,安全性管理有助于提高患者的依从性。对于接受药物去势的患者,在去势过程中不推荐常规监测雌激素水平,如怀疑不完全的OFS(包括改变用法如注射人员缺乏该药物熟练注射经验、更换剂型或出现某些可能提示卵巢功能恢复的生理变化如月经恢复或更年期症状的周期性波动时),可进行雌激素水平测定以辅助决策。绝经前乳腺癌患者如有需求,无论激素受体阳性或阴性,均可使用GnRHa保护卵巢功能,降低卵巢功能早衰的发生风险,减少生育能力损害,推荐化疗前至少1周开始使用GnRHa,每28 d 1次,直至化疗结束后2周给予最后1剂。针对激素受体阳性乳腺癌患者开展的临床试验,不推荐仅纳入绝经后人群,也应当探索GnRHa应用条件下的绝经前人群,以明确试验药物对这类患者的实际效应。另外本共识还新增了早期/局部晚期乳腺癌患者OFS药物应用的全程管理路径,以期进一步助力临床决策。

基于能量函数和改进虚拟同步控制的低频振荡抑制策略

随着可再生能源发电的普及和电力电子设备装机规模的扩大,电网稳定性显著降低,虚拟同步发电机(VSG)技术近年来备受关注。然而,VSG与同步发电机并网受到扰动时,VSG虚拟转子转速会发生突变,从而引起系统输出大幅度波动。为了抑制这些波动,本文提出一种基于超前滞后控制环的附加功率和惯量的VSG控制方法。通过引入能量函数的概念,得到一种新的控制策略。利用能量函数,分析VSG参数对系统低频振荡的影响,并通过调节VSG参数实现对VSG输出能量的控制,减少VSG与系统之间的能量流动,进而更好地抑制可再生能源发电系统的低频振荡。通过Matlab/Simulink和远宽半实物仿真平台证明了所提策略对可再生能源发电系统低频振荡具有良好的抑制效果。

听神经瘤患者经迷路切除术前后视频头脉冲试验的变化

目的:听神经瘤(acoustic neuroma,AN)是一种良性肿瘤,通常会影响患者的听觉和前庭功能。对于AN的筛查和诊断,传统方法主要依赖于听力学检查和磁共振成像(magnetic resonance imaging,MRI),而忽略了对病变部位进行前庭功能评估的重要性。视频头脉冲试验(video head impulse test,vHIT)是一种新兴的前庭功能检测方法,已广泛应用于临床,但其应用于AN诊断的研究相对较少。本研究通过在术前及术后对经迷路入路AN切除术的单侧AN患者采用v HIT进行动态检测,以探究vHIT在AN诊断、前庭功能障碍评估、术后代偿建立中的价值。方法:回顾性纳入2020年10月至2022年3月中南大学湘雅二医院耳鼻咽喉头颈外科的27例经迷路入路AN切除术单侧患者。术前1周进行v HIT以评估前庭功能,纯音测听(pure tone audiometry,PTA)评估听力水平,耳部MRI评估肿瘤大小;分别于术后1周、1个月、6个月、1年复查vHIT,并分析vHIT与听力、肿瘤大小之间的相关性。结果:术前vHIT显示患侧后半规管是前庭眼反射(vestibulo-ocular reflex,VOR)增益降低最常见的半规管。术前患侧vHIT的VOR增益与听力水平(r=-0.47,P<0.05)或肿瘤大小(r=-0.54,P<0.01)存在显著相关性。术后患侧vHIT结果显示水平半规管和前半规管的平均VOR增益随时间略有上升;3个半规管显性扫视的振幅和扫视波百分比均增加,而潜伏期时间缩短,并且在术后1周变化最明显。结论:vHIT能有效监测AN患者手术前后的前庭功能变化,对辅助诊断和治疗AN患者前庭功能障碍具有临床应用价值。

长期使用传统免疫抑制剂治疗皮肤病的不良反应比较

目的:比较患者长期(>12周)使用各传统免疫抑制剂后出现的不良反应。方法:收集2019年1月至2023年10月期间长时间(>12周)使用甲氨喋呤、环磷酰胺、环孢素、吗替麦考酚酯和沙利度胺药物的患者检查资料,对血常规、肝功能、肾功能实验室检查进行回顾性分析。结果:共1507例使用传统免疫抑制剂患者纳入分析,其中甲氨喋呤1142例,环磷酰胺135例,环孢素67例,吗替麦考酚酯66例,沙利度胺97例,不良反应发生率分别为:38.18%,56.30%,44.30%,27.27%,22.39%。最常见的不良反应依次为肝功能损伤(24.22%),肾功能损伤(12.61%)和骨髓抑制(9.69%)。患者使用免疫抑制剂引起的不良反应发生率与用药时长存在相关性。结论:长期服用传统免疫抑制剂可导致不良反应的发生,最常引起不良反应的药物为环磷酰胺。因此,对于长期服用此类药物的患者应进行定期监测。

基于递归径向基神经网络滑模的多功能柔性多状态开关控制方法

近年来,新能源和电动汽车的渗透比例逐渐增高,给配电网的潮流优化和电能质量治理带来严峻挑战。针对分布式电源的随机性和间歇性问题,设计一种基于递归径向基神经网络(RRBFNN)滑模的多功能柔性多状态开关(FMS)控制方法,在实现功率交互和多端单相接地故障柔性消弧的同时,增强FMS的抗扰能力。首先考虑扰动的影响,设计一种改进RRBFNN滑模控制方法,以克服传统滑模控制固有的抖振现象和对系统精确数学模型的依赖,并减小并网暂态冲击;柔性消弧控制采用微积分型滑模面,理论推导出0轴电压控制律,提高故障电流抑制率;进一步通过李雅普诺夫定理证明所设计方法的稳定性和收敛性。最后,在Matlab/Simulink中搭建三端口FMS及其控制系统的仿真模型,通过对比仿真验证了所提策略的可行性和有效性。

基于延迟断点映射FMCW的双功能雷达通信系统设计

基于调频连续波(Frequency Modulated Continuous Wave, FMCW)的双功能雷达通信(Dual-Functional RadarCommunication, DFRC)系统具有时频利用率高、抗多普勒性能强、距离旁瓣低的特点。现有的FMCW-DFRC波形系统产生双功能性能恶化,并增加通信接收机的链路复杂度。设计了一种基于延迟断点映射(Delayed Breakpoint Mapping, DBM)FMCW的DFRC系统,通过啁啾周期内延迟断点位置的映射和被分割的簇间的相位进行数据调制。通信接收端在载波混频和欠采样后,在数字域实现去啁啾、码片对齐和数据解调,极大降低了接收端生成相干信号和ADC性能的需求。在雷达处理链路中,设计了断点区域删除与拼接(Breakpoint Area Deletion and Splicing, BADS)方案,使DFRC的雷达性能与无调制的FMCW一致。仿真结果表明,与无补偿的方案相比,BADS方案距离图像的副瓣幅度减小约37 dB,且不受调制数据的影响。与现有基于啁啾波形的DFRC方案的通信性能相比,DBM-FMCW降低了约3 dB误符号率。

关于女性乳腺癌患者绝经状态判断两个关键问题的临床思考

内分泌治疗在激素受体阳性乳腺癌中扮演着至关重要的角色,并与患者的绝经状态密切相关。本文旨在深入探讨关于乳腺癌患者绝经状态判断的两个关键问题。第一,针对绝经前患者添加卵巢功能抑制(ovarian function suppression,OFS)治疗后,雌二醇(estradiol,E2)数值仍超标,可能存在“真性”超标和“假性”超标两种情况,氟维司群、阿贝西利、依西美坦及他莫昔芬等内分泌治疗药物可能干扰E2测定结果,需要警惕检测性“假性”超标的可能性。第二,在判断OFS治疗下患者是否已进入生理性绝经状态时,需考虑化疗对绝经状态的影响、围绝经期内分泌变化的复杂性等因素。建议根据患者年龄及内分泌治疗方案,考虑转换治疗并定期监测血清E2和卵泡刺激素(follicle-stimulating hormone,FSH)水平,针对疑难情况可综合抗缪勒管激素(anti-Mullerian hormone,AMH)、抑制素B(inhibin B,INHB)和雄激素等指标进行评估。

基于深度残差傅里叶神经算子方法压制地震多次波

多次波是一种较为严重影响地震成像的干扰波,如何有效压制多次波是需要关注的地震资料处理关键问题之一.本文基于傅里叶神经算子(FNO)和残差网络(ResNet),提出了基于深度残差傅里叶神经算子(DRFNO)网络的多次波压制方法.DRFNO是一种弱约束模型+数据驱动的人工智能算法,包含一次波和多次波的全波场炮集为输入,其中真实一次波炮集为标签训练网络,输出为压制多次波后的一次波炮集.DRFNO的网络结构中考虑了地震波场的数据特点,结合波动方程正演模拟的物理机理,约束网络训练过程.基于传统机器学习中的激活函数设置方法,该方法通过一个用于地震数据样本与标签预处理的激活函数(SDAF),克服地震炮集数据中因同相轴能量差异导致神经网络无法训练的问题.采用两套层状介质模型和Sigsbee2B复杂模型的模拟地震数据验证了DRFNO方法多次波压制处理的有效性,抗噪性和泛化能力.最后,通过一套实际地震数据实例表明本文提出的DRFNO方法应用于压制实际复杂地震波场中多次波的良好效果.

模糊PID控制在倒立摆稳摆中的噪声抑制分析

针对普通PID控制在倒立摆稳摆中不能有效抑制干扰噪声的问题,通过模糊控制算法对PID参量整定进行在线实时调整。在完成模糊PID控制器的设计应用后对倒立稳摆中的噪声抑制效果进行分析,并对影响控制效果的隶属函数选取进行探讨。结果表明:模糊PID参数整定能起到噪声抑制效果,且模糊算法使用方便,适应性强。

基于Swin-Transformer与生成对抗网络的地震随机噪声压制方法

目前深度学习类地震数据去噪方法大多基于卷积神经网络,而此类方法受限于卷积核的局部操作,缺少对地震数据全局特征的分析,因而降低了去噪效果。另外,以L 1,L 2损失函数为指标的网络模型容易出现过度平滑效应,产生虚假同相轴以及虚高的峰值信噪比(PSNR)与结构相似性(SSIM)值。为此,提出一种基于Swin-Transformer(Swin-T)和生成对抗网络的去噪方法(ST-GAN)。该方法以Swin-Transformer作为生成对抗网络中的生成网络对地震数据去噪,判别网络基于卷积神经网络。Transformer的自注意力机制是全局操作,可以有效提取地震数据的全局特征,并能与卷积神经网络的局部操作互补,提升网络模型的特征提取能力。而对抗损失则提升了网络模型的细节恢复能力,有效避免因过度平滑效应产生的同相轴假象。将该方法应用于地震数据去噪,并与现有去噪方法进行对比分析,实验结果表明,该方法具有更加优异的特征提取能力,能在有效压制随机噪声的同时,恢复和保留更多的细节信息,提高了地震信号的信噪比。