Expression Patterns of OsPIL11,a Phytochrome-Interacting Factor in Rice,and Preliminary Analysis of Its Roles in Light Signal Transduction

The expression patterns of OsPILll, one of six putative phytochrome-interacting factors, were analyzed in different organs of transgenic tobacco （Nicotiana tabacum）. The expression of OsPIL 11 was organ-specific and was regulated by leaf development, abscisic acid （ABA）, jasmonic acid （JA） and salicylic acid （SA）. To further explore the role of OsPIL 11 in plant light signal transduction, a plant expression vector of OsPILll was constructed and introduced into tobacco. When grown under continuous red light, OsPILll-overexpressed transgenic tobacco exhibited shorter hypocotyls and larger cotyledons and leaves compared to wild-type seedlings. When grown under continuous far-red light, however, transgenic and wild-type seedlings showed similar phenotypes. These results indicate that OsPILll is involved in red light induced de-etiolation, but not in far-red light induced de-etiolation in transgenic tobacco, which lays the foundation for dissecting the function of OsPIL11 in phytochrome-mediated light signal transduction in rice.

Study of light signal receptor of Stephanopyxis palmeriana during sexual reproduction

We collected centric diatom Stephanopyxis palmeriana samples in coastal waters of Xiamen for charac- teristic red light/far red light (R/FR) phytochrome reactions to identify its photoreceptor in the course of sexual repro- duction. The result showed that pre-illumination of 2-3h red light before darkness could induce sexualization of S. palmeriana, while the follow-up illumination of far red light could reverse the effect of red light, which is a featured reaction of phytochrome. The Southern Dot Blot was carried out to identify the type of phytochrome that induces the sexualization. The result also showed high homogeneity of DNA fragment of S. palmeriana with phyB, but phyA. This means the photoreceptor in the process of sexual reproduction of S. palmeriana is phytochrome B (phyB).

Regulated Degradation of HFR1 Desensitizes Light Signaling in Arabidopsis

Arabidopsis seedlings undergo photomorphogenesis in the light and etiolation in the dark. HFR1, a bHLH transcription factor, is required for both phytochrome A (phyA)-mediated far-red and cryptochrome 1 (cry1)-mediated blue light signaling. We report that HFR1 is a short-lived protein in darkness and is degraded through a 26S proteasome-dependent pathway. Light, irrespective of its quality, enhances HFR1 protein accumulation via promoting its stabilization. We demonstrate that HFR1 physically interacts with COP1 and that COP1 exhibits ubiquitin ligase activity toward HFR1 in vitro. In addition, we show that COP1 is required for degradation of HFR1 in vivo. Furthermore, plants overexpressing a C-terminal 161 amino acid fragment of HFR1 (CT161) display enhanced photomorphogenesis, suggesting an autonomous function of CT161 in promoting light signaling. This truncated HFR1 gene product is more stable than the full-length HFR1 protein in darkness, indicating that the COP1-interacting N-terminal portion of HFR1 is essential for COP1-mediated destabilization of HFR1. These results suggest that light enhances HFR1 protein accumulation by abrogating COP1-mediated degradation of HFR1, which is necessary and sufficient for promoting light signaling. Additionally, our results substantiate the E3 ligase activity of COP1 and its critical role in desensitizing light signaling.

基于深度学习的可见光通信系统室内三维定位

针对目前室内可见光通信系统三维定位的准确率与定位速度依然不佳的问题,提出一种基于深度学习的可见光通信系统室内定位方法。首先,设计了一个神经网络将指纹数据编码成二维阵列,利用卷积神经网络学习指纹阵列与目标位置之间的关系;然后,通过粒子群优化算法自动搜索卷积神经网络的超参数,以降低深度神经网络的训练难度。此外,设计了定位数据训练集、验证集与测试集的划分方法,有助于缓解神经网络的过拟合问题,并提高定位准确性。仿真结果表明,所提方法在6×6×4m3室内环境下的平均定位误差为0.024m,平均定位时间为0.478s。

Modulation of starch synthesis in Arabidopsis via phytochrome B-mediated light signal transduction

Starch is a major storage carbohydrate in plants and is critical in crop yield and quality.Starch synthesis is intricately regulated by internal metabolic processes and external environmental cues;however,the precise molecular mechanisms governing this process remain largely unknown.In this study,we revealed that high red to far-red(high R:FR)light significantly induces the synthesis of leaf starch and the expression of synthesis-related genes,whereas low R:FR light suppress these processes.Arabidopsis phytochrome B(phyB),the primary R and FR photoreceptor,was identified as a critical positive regulator in this process.Downstream of phyB,basic leucine zipper transcription factor ELONGATED HYPOCOTYL5(HY5)was found to enhance starch synthesis,whereas the basic helix-loop-helix transcription factors PHYTOCHROME INTERACTING FACTORs(PIF3,PIF4,and PIF5)inhibit starch synthesis in Arabidopsis leaves.Notably,HY5 and PIFs directly compete for binding to a shared G-box cis-element in the promoter region of genes encoding starch synthases GBSS,SS3,and SS4,which leads to antagonistic regulation of their expression and,consequently,starch synthesis.Our findings highlight the vital role of phyB in enhancing starch synthesis by stabilizing HY5 and facilitating PIFs degradation under high R:FR light conditions.Conversely,under low R:FR light,PIFs predominantly inhibit starch synthesis.This study provides insight into the physiological and molecular functions of phyB and its downstream transcription factors HY5 and PIFs in starch synthesis regulation,shedding light on the regulatory mechanism by which plants synchronize dynamic light signals with metabolic cues to module starch synthesis.

RACK1A promotes hypocotyl elongation by scaffolding light signaling components in Arabidopsis

Plants deploy versatile scaffold proteins to intricately modulate complex cell signaling.Among these,RACK1A(Receptors for Activated C Kinase 1A)stands out as a multifaceted scaffold protein functioning as a central integrative hub for diverse signaling pathways.However,the precise mechanisms by which RACK1A orchestrates signal transduction to optimize seedling development remain largely unclear.Here,we demonstrate that RACK1A facilitates hypocotyl elongation by functioning as a flexible platform that connects multiple key components of light signaling pathways.RACK1A interacts with PHYTOCHROME INTERACTING FACTOR(PIF)3,enhances PIF3 binding to the promoter of BBX11 and down-regulates its transcription.Furthermore,RACK1A associates with ELONGATED HYPOCOTYL 5(HY5)to repress HY5 biochemical activity toward target genes,ultimately contributing to hypocotyl elongation.In darkness,RACK1A is targeted by CONSTITUTIVELY PHOTOMORPHOGENIC(COP)1 upon phosphorylation and subjected to COP1-mediated degradation via the 26 S proteasome system.Our findings provide new insights into how plants utilize scaffold proteins to regulate hypocotyl elongation,ensuring proper skoto-and photo-morphogenic development.

基于深度学习的水下激光通信系统弱光信号检测方法研究

水下激光通信系统弱光信号受到频谱和多径干扰,检测的精度不高,为了提高水下激光通信的稳定性,提出基于深度学习的水下激光通信系统弱光信号检测方法。采用空间波束形成方法构建水下激光通信采集和多层频谱分解模型,实现信号的波束特征增强处理,结合时间反转技术估计弱光信号的射频标签分布信息和多径信息,采用多径衰落抑制实现对水下激光通信系统的弱光信号增强处理,利用深度学习算法进行弱光信号检测过程中的寻优控制,使得整个信号检测过程保证在恒虚警概率。仿真结果表明,该方法进行水下激光通信系统弱光信号检测对多径衰落的抑制能力较好,不同信噪比环境下误码率较低,当信噪比增大至90 dB时,其误码率仅为10-5,且其检测时间小于10 ms,优于对比方法,具有更大的应用价值。

无线紫外光MIMO通信系统信道容量估算方法

无线紫外光通信系统易受大气散射等因素的影响,导致通信信道容量估算准确率较低。为此,提出一种无线紫外光多入多出(Multiple-Input Multiple-Output, MIMO)通信系统信道容量估算方法。根据信道特征,构建无线紫外光MIMO通信系统的信道容量估计模型,获取无线紫外光的单次散射传输特性,利用符号补码式的方法改进空时编码,设定高级检测器中符号的接收能耗,使每个符号保持在标准功率数值范围内,完成通信系统信道检测式编码。根据不同发射角和接收角计算无线紫外光通信的路径损耗比,通过泊松随机分布获得最终通信系统信道容量的估算结果。实验结果表明,所提方法的传输速率可高达8 Mbps,误码率始终低于10-3bit/s,估算准确率在90%以上,估计时间低于4 ms,估算效果好,可为通信行业发展提供理论依据。

浅析媒体立面照明——以柳州国际会展中心为例

随着夜景经济的快速发展,媒体立面已经成为城市夜景工程表现的主要手段之一。本文以柳州国际会展中心建筑照明设计为例,从灯具选择、布置密度、安装方式、信号传输、控制系统等方面分析媒体立面效果实现的因素,确保媒体立面在项目方案实施中的落地,为今后建筑媒体立面的设计提供参考。

基于计算机网络和通信控制的智能化铁路信号机点灯系统的实现

铁路信号机点灯系统关系着列车运行安全与运输效率,也有助于改善工作环境,在铁路现代化建设中发挥着重要作用。在新世期,铁路信号机点灯系统逐渐智能化与自动化。文中简单介绍了铁路信号机的基本原理,系统论述了基于计算机网络和通信控制的智能化铁路信号机点灯系统的运行指导思想,并从优化智能信号灯控板、设置好LED发光盘、配置电源模块与机柜、加强铁路信号机点灯系统保护等4个方面,分层浅谈了智能化铁路信号机点灯系统的设计方案。

离岸直升机平台助降信号指示系统的设计

为提高海洋工程井架平台、舰船等离岸装备上的直升机助降活动的安全性,研究了一种直升机离岸直升机平台助降信号指示系统。该系统由照明及控制装置组成,经第三方检验机构验证该平台技术性能符合国内外相关标准的要求,部分技术性能达到了国际领先水平。

工业光总线控制系统在流程工业中的应用研究

传统分散控制系统信息传输过程中出现的中间断点,会影响线路阻值和信号稳定性。提出了一种工业光总线控制系统,介绍了该控制系统中智能数据传输单元及工程设计中的注意事项,并对比了该系统与分散控制系统在建设过程中费用控制、进度控制、质量控制方面的优势,分析了利用该系统代替其他控制系统的可行性。该系统采用现场智能IO技术,用光信号代替电信号,通过分析表明:该系统在经济性、信号稳定性、施工、设计、进度控制上都具有优势。

路径规划及信号灯控制的智能优化

由于全智能化的交通控制系统尚未得到完全普及,道路交通资源占用时空二维不够均衡、城市交通规划策略与通行车辆规模不够匹配,导致城市交通拥塞、车辆准点率低等问题。针对上述问题,首先构建了基于服务员休假的多队列多服务员排队模型和级联队列的多跳排队模型,分析了在十字路口处及一般道路情况下车辆流量、信号灯时长与通勤时延的理论关系;然后提出了基于近端策略优化的路径规划及信号灯控制的智能优化方法,通过动态感知城市实时交通拥塞状态,联合规划车辆最优路径和控制信号灯最优时长,从而最大化车辆准点率。仿真结果表明,所提方法比于自适应高效联邦对比方法在时延性能方面提升了3倍以上,在车辆准点率方面提升了18%左右。

Light regulation of horticultural crop nutrient uptake and utilization

Plants demonstrate dynamic changes in molecular structures under fluctuating light conditions.Accumulating evidence suggests that light plays a vital role in plant growth and morphogenesis.In particular,light has a role in the absorption and utilization of nutrients in plants.Despite significant progress in understanding the mechanism of nutrient acquisition and assimilation,how light affects and regulates ion uptake remains a question.Studies in model plants,Arabidopsis thaliana,suggest that light affects the nutrient utilization in roots through a complex regulatory network;nonetheless,the molecular mechanisms underlying the various effects of light on these processes in crop plants remain fragmentary.In this review,we discuss the light effects(light quality,light intensity,and photoperiod)on nutrient uptake and utilization in horticultural crops for optimizing crop productivity and increasing fertilizer use efficiency.

Technique of Position Sensitive Detector with Alternating Light Source

The signal processing circuits of position sensitive detector(PSD) with alternating light source are presented.The measuring device of PSD with alternating light source can effectively eliminate the interference made by light noise signal.

The DELLA-ABI4-HY5 module integrates light and gibberellin signals to regulate hypocotyl elongation

Plant growth is coordinately controlled by various environmental and hormonal signals,of which light and gibberellin(GA)signals are two critical factors with opposite effects on hypocotyl elongation.Although interactions between the light and GA signaling pathways have been studied extensively,the detailed regulatory mechanism of their direct crosstalk in hypocotyl elongation remains to be fully clarified.Previously,we reported that ABA INSENSITIVE 4(ABI4)controls hypocotyl elongation through its regulation of cellelongation-related genes,but whether it is also involved in GA signaling to promote hypocotyl elongation is unknown.In this study,we showthat promotion of hypocotyl elongation by GA is dependent on ABI4 activation.DELLAs interact directly with ABI4 and inhibit its DNA-binding activity.In turn,ABI4 combined with ELONGATED HYPOCOTYL 5(HY5),a key positive factor in light signaling,feedback regulates the expression of the GA2ox GA catabolism genes and thus modulates GA levels.Taken together,our results suggest that the DELLA-ABI4-HY5 module may serve as a molecular link that integrates GA and light signals to control hypocotyl elongation.

The GmSTF1/2–GmBBX4 negative feedback loop acts downstream of blue-light photoreceptors to regulate isoflavonoid biosynthesis in soybean

Isoflavonoids,secondary metabolites derived from the phenylalanine pathway,are predominantly bio-synthesized in legumes,especially soybean(Glycine max).They are not only essential for plant responses to biotic and abiotic stresses but also beneficial to human health.In this study,we report that light signaling controls isoflavonoid biosynthesis in soybean.Blue-light photoreceptors(GmCRY1s,GmCRY2s,GmPHOT1s,and GmPHOT2s)and the transcription factors GmSTF1 and GmSTF2 promote isoflavonoid accumulation,whereas the E3 ubiquitin ligase GmCOP1b negatively regulates isoflavonoid biosynthesis.GmPHOT1s and GmPHOT2s stabilize GmSTF1/2,whereas GmCOP1b promotes the degradation of these two proteins in soybean.GmSTF1/2 regulate the expression of approximately 27.9%of the genes involved in soybean isoflavonoid biosynthesis,including GmPAL2.1,GmPAL2.3,and GmUGT2.They also repress the expression of GmBBX4,a negative regulator of isoflavonoid biosynthesis in soybean.In addition,GmBBX4 physically interacts with GmSTF1 and GmSTF2 to inhibit their transcriptional activation activity toward target genes related to isoflavonoid biosynthesis.Thus,GmSTF1/2 and GmBBX4 form a negative feedback loop that acts downstream of photoreceptors in the regulation of isoflavonoid biosynthesis.Our study provides novel insights into the control of isoflavonoid biosynthesis by light signaling in soybean and will contribute to the breeding of soybean cultivars with high isoflavonoid content through genetic and metabolic engineering.

汽车灯光信号系统原理及故障案例分析

以广汽传祺GS4车型的灯光信号系统控制电路图为例,介绍了汽车灯光信号系统的结构和原理。通过导入车辆位置灯、转向灯、雾灯、制动灯异常闪烁案例(左、右后组合A灯),探讨故障原因及解析思路,并通过电路结构简图对异常闪烁现象进行分析。结果表明,共用G403接地点使用的为普通螺栓,无破漆功能,导致G403无接地。当转向灯、位置灯、制动灯、雾灯全部为打开状态,会因为二极管、卤素灯的特性,在电路内部形成电位差,又因为BCM向转向灯输出为脉冲电压,会形成电位差的变化,就会导致位置灯、制动灯、雾灯与转向灯的交互闪烁,且电尾门无法关闭。

20.231 Gbit/s tricolor red/green/blue laser diode based bidirectional signal remodulation visible-light communication system

We propose and experimentally demonstrate a recorded 1-m bidirectional 20.231-Gbit/s tricolor R/G/B laser diode(LD) based visible-light communication(VLC) system supporting signal remodulation. In the signal remodulation system, an LD source is not needed at the client side. The client reuses the downstream signal sent from the central office(CO) and remodulates it to produce the upstream signal. As the LD sources are located at the CO, the laser wavelength and temperature managements at the cost-sensitive client side are not needed.This is the first demonstration, to our knowledge, of a >20 Gbit∕s data rate tricolor R/G/B VLC signal transmission supporting upstream remodulation.

主辅灯信号系统的辅灯信号控制方法的研究

城市道路人行横道是除交叉口外的重要的交通冲突区域,协调人行横道处的机动车流和行人过街等非机动车流的行为冲突具有重要意义。针对目前人行横道行人过街组织方式存在的弊端,采用基于行人过街请求的主辅灯信号联动控制策略控制人行横道交通行为。首先提出了主辅灯信号系统的辅灯控制方法原理;其次研究基于行人过街请求和主灯控制器信号配时的信号控制策略,实现满足行人过街请求前提下的车辆通行最优化控制方法;最后设计一种行人过节请求的辅灯控制器,通过设计相应功能模块,实现辅灯信号控制策略。模拟实验方案结果表明:在不同信号状态下触发行人过街请求信息,辅灯控制策略模型能够准确输出的辅灯信号的配时方案,在实施该信号控制策略后,车辆通过交叉口和辅灯人行横道区域的通行效率明显增加。