Dissection of QTLs for Yield Traits on the Short Arm of Rice Chromosome 6

This study was undertaken to dissect quantitative trait loci （QTLs） controlling yield traits on the short arm of rice chromosome 6. A residual heterozygous line that carries a heterozygous segment extending from RM587 to RM19784 on the short arm of rice chromosome 6 was selected from an F7 population of the indica rice cross Zhenshan 97B/Milyang 46. An F2：3 population consisting of 221 lines was derived and grown in two trial sites. Six yield traits including number of panicles per plant, number of filled grains per panicle, total number of spikelets per panicle, spikelet fertility, 1 000-grain weight, and grain yield per plant were measured. An SSR marker linkage map was constructed and employed to determine QTLs for yield traits with Windows QTL Cartographer 2.5. QTLs were detected in the target interval for all the traits analyzed except NP, with phenotypic variance explained by a single QTL ranging between 6.3% and 35.2%. Most of the QTLs for yield components acted as additive QTLs, while the three QTLs for grain yield had dominance degrees of 1.65, 0.84, and -0.42, respectively. It was indicated that three or more QTLs for yield traits were located in the target region. The genetic action mode, the direction of the QTL effect, and the magnitude of the QTL effect varied among different QTLs for a given trait, and among QTLs for different traits that were located in the same interval.

Quantitative Trait Loci for Panicle Size and Grain Yield Detected in Interval RM111-RM19 784 on the Short Arm of Rice Chromosome 6

A rice residual heterozygous line （RHL） carrying a heterozygous segment extending from RM111 to RM19784 on the short arm of rice chromosome 6 was selected from a RHL-derived population used previously. The resultant F2：3 population was used to detect quantitative trait loci （QTLs） for three yield traits, the number of spikelets per panicle （NSP）, the number of grains per panicle （NGP） and grain yield per plant （GY）. Two QTLs for NSP, one QTL for NGP and one QTL for GY were detected, all of which were partially dominant and had the enhancing alleles from the maternal line Zhenshan 97B. Analysis based on the genotypic groups of the markers closely linked to the two QTLs for NSP indicated that they did not interact with each other. Two F2 populations and two near isogenic line （NIL） sets segregating in two sub-regions of interval RM111-RM19784 were developed. The two QTLs for NSP were validated, of which one had major effect and was co-segregated with heading date gene Hdl, and the other had smaller effect and was located in an upper region linked to Hdl. The two regions also showed significant effects on the number of filled grain and grain yield, although the effect on the number of filled grain was less consistent.

“Sitting-up vertigo as an expression of posterior semicircular canal heavy cupula and posterior semicircular canal short arm canalolithiasis”

Background:Vestibular symptoms on sitting-up are frequent on patients seen by vestibular specialists.Recently,a benign paroxysmal positional vertigo(BPPV)variant which elicits vestibular symptoms with oculomotor evidence of posterior semicircular canal(P-SCC)cupula stimulation on sitting-up was described and named sitting-up vertigo BPPV.A periampullar restricted P-SCC canalolithiasis was proposed as a causal mechanism.Objective:To describe new mechanisms of action for the sitting-up vertigo BPPV variant.Methods:Eighteen patients with sitting-up vertigo BPPV were examined with a pre-established set of positional maneuvers and follow-up until they resolved their symptoms and clinical findings.Results:All patients showed up-beating torsional nystagmus(UBTN)and vestibular symptoms on coming up from either Dix-Hallpike(DHM)or straight head-hanging maneuver.Sixteen out of 18 patients presented a sustained UBTN with an ipsitorsional component to the tested side on half-Hallpike maneuver(HH).A slower persistent contratorsional down-beating nystagmus was found in eleven out18 patients tested on nose down position(ND).Conclusions:Persistent direction changing positional nystagmus on HH and ND positions indicative of PSCC heavy cupula was found in 11 patients.A sustained UBTN on HH with the absence of findings on ND,which is suggestive of the presence of P-SCC short arm canalolithiasis,was found on 5 patients.All patients were treated with canalith repositioning maneuvers without success,but they resolved their findings by means of Brandt-Daroff exercises.We propose P-SCC heavy cupula and P-SCC short arm canalolithiasis as two new putative mechanisms for the sitting-up vertigo BPPV variant.

Short arm cast is as effective as long arm cast in maintaining distal radius fracture reduction:Results of the SLA-VER noninferiority trial

BACKGROUND Distal radius fractures(DRFs)are a common challenge in orthopaedic trauma care,yet for those fractures that are treated nonoperatively,strong evidence to guide cast treatment is still lacking.AIM To compare the efficacy of below elbow cast(BEC)and above elbow cast(AEC)in maintaining reduction of manipulated DRFs.METHODS We conducted a prospective,monocentric,randomized,parallel-group,open label,blinded,noninferiority trial comparing the efficacy of BEC and AEC in the nonoperative treatment of DRFs.Two hundred and eighty patients>18 years of age diagnosed with DRFs were successfully randomized and included for analysis over a 3-year period.Noninferiority thresholds were defined as a 2 mm difference for radial length(RL),a 3°difference for radial inclination(RI),and volar tilt(VT).The trial is registered at Clinicaltrials.gov(NCT03468023).RESULTS One hundred and forty-three patients were treated with BEC,and 137 were treated with AEC.The mean time of immobilization was 33 d.The mean loss of RL,RI,and VT was 1.59 mm,2.83°,and 4.11°for BEC and 1.63 mm,2.54°,and VT loss were respectively 0.04 mm(95%CI:-0.36-0.44),-0.29°(95%CI:-1.03-0.45),and 0.59°(95%CI:-1.39-2.57),and they were all below the prefixed noninferiority thresholds.The rate of loss of reduction was similar.CONCLUSION BEC performs as well as AEC in maintaining the reduction of a manipulated DRF.Being more comfortable to patients,BEC may be preferable for nonoperative treatment of DRFs.

基于ARM处理器的手机短消息加密系统

介绍了一种基于ARM处理器的基于身份加密的手机短消息加密系统。本系统以S3C2410作为处理器、TC35作为GSM模块、嵌入式Linux作为操作系统,采用基于身份加密算法,对短消息中的敏感内容进行加密处理,并对存储在手机中的私钥进行非交互式更新。测试表明本系统满足机密性和实时性要求,同时还具有前向安全性,即使手机丢失,以前的加密短消息依然是保密的。本系统能够为移动商务提供安全的短信传输。

用ARM控制CDMA无线Modem发送短消息

文中介绍了一种新的机器人通讯方式,即用ARM控制CDMA无线Modem发送短消息。文章对ARM中特殊寄存器的设置进行了示例介绍,同时详细介绍了CDMA无线Modem如何使用AT指令发送短消息。

短壁工作面回采巷道围岩变形破坏特征及控制技术研究

针对辛置煤矿短壁工作面回采巷道围岩破坏情况,通过FLAC3D数值模拟软件,分析其塑性区扩展形态、剪应力演化形态、采动支承应力分布规律,结合现场实际情况,设计了适用于防冲性的回采巷道顶板强护顶支护方案,既能有效控制顶板变形,还增加了现场施工速度,提高了短壁煤柱工作面回收速度,现场应用效果良好,为同类型地质条件回采巷道围岩控制提供一定思路。

基于ARM与GSM的智能家居控制器设计

设计了一种基于ARM和GSM技术的智能家居控制器,主要功能的实现是通过手机短信对家居进行远程控制。中央控制器采用了目前较为流行的ARM,既能实现对单一家电的控制,也可实现对多种家电的控制。

急倾斜煤层回采参数研究

近年来由于煤炭资源的不断开采,矿井深度增加导致煤层地质条件不断恶化,尤其是急倾斜煤层的回采工作,对开采工艺有着极高的要求。结合当前急倾斜煤层开采工艺现状,通过分析急倾斜煤层回采参数,提出一种新型斜坡短臂采煤工艺,为该类复杂型煤层的开采提供借鉴。

基于ARM的高精度毫米波雷达测距传感器

针对其他非接触式雷达在复杂环境下抗干扰能力差及传统毫米波雷达结构复杂等问题,提出了一种基于FMCW的V波段高精度雷达传感器测距装置。该装置不同于传统毫米波雷达的波导及微波模块组合的设计思路,以高度集成的单片60 GHz毫米波雷达传感器芯片为核心对各子系统进行开发研究。RF子系统产生、发射V波段FMCW信号并在对回波信号进行放大、滤波及混频得到中频信号后,由DSP实时处理子系统处理得到距离,通过UART串口传输到上位机中进行显示,整个过程由ARM子系统全局控制。在微波暗室中的实验结果表明,对于近程单一静止目标,测距位移精度达到0.1 mm。该装置的研究对于推进近程高精度测距毫米波雷达的开发具有重要价值。

基于Linux的ARM9嵌入式Web服务器设计研究

本文提出了一种嵌入式Web服务器的设计方案,并详细阐述了对基于ARM和Linux的嵌入式Web服务器系统的软硬件体系结构.在此设计基础上,初步实现了嵌入式远程控制系统.实验表明,该系统在Linux和Windows环境下可通过浏览器与嵌入式系统进行动态网页交互,亦可通过短信息对嵌入式系统进行访问.

具备直流短路故障阻断能力的子模块桥臂复用型模块化多电平固态变压器

模块化多电平换流器的固态变压器(modular multilevel converter based solid state transformer,MMC-SST)由于具备多电压等级、多电压形态的端口,在交直流混合配电网中得到广泛关注。传统的输入串联输出并联(inputseriesoutput parallel,ISOP)型MMC-SST具有较高的功率密度,但是在中压直流(medium voltage DC,MVDC)端口短路故障情况下无法持续向低压侧供电;双向有源全桥变换器(dualactive bridge,DAB)型MMC-SST则存在功率密度低、成本高等问题,并且传统的半桥结构的DAB型MMC-SST在MVDC端口短路故障情况下同样无法持续向低压侧供电。文章提出了一种子模块桥臂复用(arm integrated submodule,AISM)型MMC-SST拓扑,在不改变MMC-SST端口电气特性的情况下,在有效减少开关器件数量的同时,还使得SST具备中压直流端口短路故障下的不间断运行能力,进而提升SST的功率密度和供电可靠性。针对文中提出的AISM型MMCSST拓扑,该文还提出了一种针对输入级MMC的混频调制方法,基于共模、差模解耦原理,实现输入级MMC桥臂电压的高频分量和低频分量的解耦。通过理论分析与仿真模拟,验证了所提拓扑及控制方法的可行性。

基于长短期记忆神经网络的采煤机摇臂轴承剩余寿命预测

为解决采煤机摇臂关键零部件的失效问题,基于长短期记忆神经网络(Long Short-Term Memory,LSTM)提出了一种创新性的方法,以预测采煤机摇臂轴承的剩余寿命。基于长短期记忆神经网络理论,通过建立轴承寿命退化指标,对轴承剩余寿命进行预测,同构利用分层抽样方法对数据集进行划分;通过引入粒子群算法优化LSTM,解决LSTM算法选择最优超参数的问题,提高轴承剩余寿命预测精度。研究结果表明,基于LSTM的轴承剩余寿命预测结果与实际轴承寿命变化情况基本一致,预测结果均在置信区间内,可以为轴承维修保养工作提供参考。

基于ARM的嵌入式自动笛语识别系统

设计并实现了一种基于ARM9的嵌入式自动笛语识别系统。该系统由ARMS3C2410微处理器和UDA1341专用语音芯片为核心,配合其他功能电路,能实时自动识别汽车笛语。系统采用短时能量法,并引入动态能量阈值排除噪声。试验结果表明,该系统能够在不同的噪声环境下,准确地自动识别出各种不同车辆笛语的意义,能够满足实时系统的需要。

基于孪生模型的模块化多电平换流器保护

随着柔性直流输电技术的发展,模块化多电平换流器(MMC)由于其拓扑优势越来越受到关注。作为直流输电换流阀的主要元件,子模块与桥臂电抗器故障将对换流站安全稳定运行造成严重影响,现有差动保护均无法有效识别此类故障。文中提出了基于孪生模型的MMC保护原理,结合MMC的控制信息建立数字孪生模型,通过动态状态估计构建保护判据。所提保护方案能够准确检测MMC换流器故障,包括桥臂电抗器匝间短路故障、子模块开路故障及桥臂相间短路故障。根据保护动作类型提出两套保护判据。仿真结果表明,所提保护方案能够可靠地自适应辨识MMC区内故障,具有良好的速动性以及耐受过渡电阻能力。

基于ARM全数字化CO_2气体保护焊的研究

CO2气体保护焊具有效率高、成本低、形变小、抗锈能力强等优点,在工业中应用广泛。国内电焊机在数字化方面的研究起步虽晚,但发展迅速。在电弧数学建模、控制算法的基础上,运用ST公司的32位ARM微处理器对CO2气体保护焊的全数字化系统进行了研究、设计与实现。CO2气体保护焊熔滴过渡存在短路、燃弧交替变化的特点,针对系统参数变化大、扰动复杂的情况,应用现代控制理论设计了熔滴短路过渡电流的模糊自适应PI控制器,在线识别电弧实时状态,改变控制量,保证系统控制品质在最佳范围,借鉴STT的控制策略,并在STM32F103微处理器上调试通过,获得了较好的焊接效果,实现了CO2气体保护焊的全数字化控制:控制算法数字化、功率输出数字化、馈丝系统数字化以及人机交互界面数字化。

环境相关浓度的氟西汀和帕罗西汀对章鱼脑组织五羟色胺能系统的影响

近年来,随着抑郁症患者数量激增,抗抑郁性药物的使用量显著增加。由于药物具有特殊活性,常会对非目标生物的生理功能产生不良影响,干扰这些生物的生长发育,对其健康产生严重威胁。因此,本研究选取通过抑制五羟色胺(serotonin,5-HT)转运体提高突触间隙5-HT水平发挥治疗作用的SSRI(selective serotonin reuptake inhibitor)类抗抑郁代表性药物氟西汀和帕罗西汀,探讨2种药物对章鱼脑组织5-HT能神经递质系统功能的影响。野生成体短蛸章鱼(O.ochellatus)于环境浓度的氟西汀、帕罗西汀溶液中连续暴露14 d,收集脑组织。通过qPCR和Western blot技术分析药物对章鱼脑组织5-HT能神经递质系统主要功能分子转录及表达水平的影响。结果显示,氟西汀和帕罗西汀引起章鱼脑组织中5-HT能系统重要功能分子转录及表达水平异常,表现为5-HTR1、5-HTR1B、5-HTR2A、SERT mRNA转录水平降低及5-HTR1、5-HTR1B、5-HTR2A、SERT蛋白表达水平升高,且具有药物特异性和剂量依赖性。此外,氟西汀与帕罗西汀混合暴露对章鱼脑5-HT能系统的影响程度弱于两者单独暴露,提示2种药物在干扰章鱼脑5-HT能系统正常功能过程中可能存在拮抗作用,通过比较二者的半衰期,认为氟西汀对于水生生态系统的影响更大。本研究结果表明,SSRI类抗抑郁药物氟西汀和帕罗西汀暴露可引起章鱼脑组织5-HT能神经系统主要功能分子转录与表达水平异常,可能干扰其正常功能,严重威胁章鱼健康。本研究为进一步研究抗抑郁症药物对章鱼神经系统的不良影响提供科学依据,为研究其他药物对海洋生物的健康损害效应提供参考。

短壁采煤机双级摇臂及回转机构设计

针对常规单滚筒短壁采煤机采高小,摇臂回转能力不足的问题,设计了一种用于短壁采煤机的新型双级摇臂。介绍了双级摇臂的结构形式、双传动系统以及摇臂回转机构。一级摇臂在主油缸推动下可有限角度摆动,二级摇臂在回转机构驱动下可正反360°回转。回转机构采用马达和回转减速器的传动方式。通过计算截煤工况下的最大外负载,确定了回转机构所需的最大回转力矩。

采煤机调高驱动装置的研究

采煤机调高驱动装置将常规的油缸或齿轮齿条的直线往复运动更改为液压马达驱动行星传动机构,以此实现圆周运动。便于实现双层机身、上下式纵向布置、多臂联动等功用。采用先进的控制理念,通过液压马达集成式控制模块,实现过载与摇臂抖动的保护。多片湿式制动器的设计为摇臂在大截割功率下提供了稳定性,同时考虑到制动器的响应速度,实现功率合理利用。该装置采用了逻辑控制回路,极大缩小了该装置的安装空间和产品质量,同时又具有较高的响应速度和同步性,因此适用于各类短臂式大采高采煤机,可为采煤机的维护人员和研究设计者提供参考。

双级摇臂单滚筒短壁采煤机采煤工艺分析

根据双级摇臂单滚筒短壁采煤机两级摇臂联动和小直径滚筒双向截煤的特点,提出了“单刀分层往返”的采煤工艺并确定了相应的作业流程。根据不同采高需求,制定了两级摇臂联动调姿策略。通过综合考虑进刀方式、滚筒旋向和二级摇臂位姿等多耦合因素,定性分析了回转机构所受外负载的影响规律。以回转机构所受外负载最小为优化目标,确定在不同工作面的最佳采煤工艺路线,为现场作业提供理论指导。