QTL Detection for Rice Grain Shape Using Chromosome Single Segment Substitution Lines

Rice grain shape is one of the important factors affecting grain quality and yield,but it is liable to be influenced by genetic backgrounds and environments.The chromosome single segment substitution lines(SSSLs) in rice have been considered as ideal populations to identify the quantitative trait loci(QTLs).In this study,22 QTLs affecting rice grain shape were detected to be distributed on eight chromosomes except chromosomes 6,9,11 and 12 by using SSSLs.Among them,seven QTLs conditioned grain length,six conditioned grain width,five affected grain length-width ratio and four controlled grain thickness.

Study on the automatic process of line heating for pillow shape plate

This paper focuses on the process for pillow shape plate by line heating technique, which is widely applied in the production of ship hull. Based on the analysis of primary parameters and experimental data in line heating process, the amount of local contraction generated by line heating has been illustrated. Then, combining with the computational result of local deformation determined by shell plate development, an optimization method for line heating parameters has been studied. This prediction system may provide rational arrangements of heating lines and technical parameters of process. By integrating the prediction system into the line heating robot for pillow shape plate, the automatic process of line heating for pillow shape plate can be achieved.

Experimental demonstration of an invisible cloak with irregular shape by using tensor transmission line metamaterials

We present the design and the experimental demonstration of an invisible cloak with irregular shape by using tensor transmission line（TL） metamaterials. The fabricated cloak consists of tensor TL unit cells exhibiting anisotropic effective material parameters, while the background medium consists of isotropic TL unit cells. The simulated and the measured field patterns around the cloak show a fairly good agreement, both demonstrate that the fabricated cloak can shield the cloaked interior area from electromagnetic fields without perturbing the external fields. The scattering of the cloaked perfect electric conductor（PEC） is minimized. Furthermore, the nonresonant property of the TL structure results in a relatively broad bandwidth of the realized cloak, which is clearly observed in our experiment.

Femtosecond Stimulated Raman Line Shapes:Dependence on Resonance Conditions of Pump and Probe Pulses

Resonance enhancement has been increasingly employed in the emergent felntosecond stimu- lated Raman spectroscopy （FSRS） to selectively monitor molecular structure and dynamics with improved spectral and temporal resolutions and signal-to-noise ratios. Such joint eflforts by the technique- and application-oriented scientists and engineers have laid the foundation for exploiting the tunable FSRS methodology to investigate a great variety of photosensitive systems and elucidate the underlying functional mechanisms on molecular time scales. Dur- ing spectral analysis, peak line shapes remain a major concern with an intricate dependence on resonance conditions. Here, we present a comprehensive study of line shapes by tuning the Rarnan pump wavelength from red to blue side of the ground-state absorption band of the fluorescent dye rhodarnine 6G in solution. Distinct line shape patterns in Stokes and anti-Stokes FSRS as well as from the low to high-frequency modes highlight the competition between multiple third-order and higher-order nonlinear pathways, governed by difl^rent res- onance conditions achieved by Raman pump and probe pulses. In particular, the resonance condition of probe wavelength is revealed to play an important role in generating circular line shape changes through oppositely phased dispersion via hot luminescence （HL） pathways. Meanwhile, on-resonance conditions of the Rarnan pump could promote excited-state vibrational modes which are broadened and red-shifted from the coincident ground-state vibrational modes, posing challenges for spectral analysis. Certain strategies in tuning the Raman pump and probe to characteristic regions across an electronic transition band are discussed to improve the FSRS usability and versatility as a powerful structural dynamics toolset to advance chemical, physical, materials, and biological sciences.

The Line Shape of Double-Sided Tooth-Disk Waveguide Filters Based on Plasmon-Induced Transparency

We numerically investigate a coupled-resonator structure consisting of a stub resonator and a nanodisk resonator using a two-dimensional finite element method. Simulation results show that plasmon-induced transparency （PIT） occurs in the transmission spectra, and the sharp asymmetric Fano lines increase the sensitivity to 1.4 ×10^3 nm/RIU. We also analyze the properties of the structure with different radii of the nanodisk and the length of the tooth cavity. Moreover, we find that the PIP only happens when the staggered system is around a fixed location with different separate distances, which is not similar to the previous researches. Our model may be important to photonic-integrated circuits and the sensitivity in sensors.

Study on a W-band modified V-shaped microstrip meander-line traveling-wave tube

The study on a miniaturized, low-voltage, wide-bandwidth, high-efficiency modified V-shaped microstrip meander-line slow-wave structure is presented. This structure is evolved from the original U-shaped microstrip meander-line slow-wave structure, combining the advantages of a traditional microstrip and a rectangular helix. In this paper, simulations of the electromagnetic characteristics and the beam-wave interaction of this structure are carried out. Our study shows that when the design voltage and the current of a sheet electron beam are set to be 4700 V and 100 mA, respectively, this miniature millimeter-wave power amplifier is capable of delivering 160-W output power with a corresponding gain of 37.3 dB and a maximum interaction efficiency of 34% at 97 GHz.

利用Alpha Shapes算法提取离散点轮廓线

本文介绍了Alpha Shapes算法的原理和具体的实现方法,并将其应用到LiDAR离散点云数据的轮廓线提取,取得良好效果。

Mechanical Behavior and Shape Optimization of Lining Structure for Subsea Tunnel Excavated in Weathered Slot

Subsea tunnel lining structures should be designed to sustain the loads transmitted from surrounding ground and groundwater during excavation. Extremely high pore-water pressure reduces the effective strength of the country rock that surrounds a tunnel, thereby lowering the arching effect and stratum stability of the structure. In this paper, the mechanical behavior and shape optimization of the lining structure for the Xiang＇an tunnel excavated in weathered slots are examined. Eight cross sections with different geometric parameters are adopted to study the mechanical behavior and shape optimization of the lining structure. The hyperstatic reaction method is used through finite element analysis software ANSYS. The mechanical behavior of the lining structure is evidently affected by the geometric parameters of crosssectional shape. The minimum safety factor of the lining structure elements is set to be the objective function. The efficient tunnel shape to maximize the minimum safety factor is identified. The minimum safety factor increases significantly after optimization. The optimized cross section significantly improves the mechanical characteristics of the lining structure and effectively reduces its deformation. Force analyses of optimization process and program are conducted parametrically so that the method can be applied to the optimization design of other similar structures. The results obtained from this study enhance our understanding of the mechanical behavior of the lining structure for subsea tunnels. These results are also beneficial to the optimal design of lining structures in general.

Rock mass response for lined rock caverns subjected to high internal gas pressure

The storage of hydrogen gas in underground lined rock caverns(LRCs)enables the implementation of the first fossil-free steelmaking process to meet the large demand for crude steel.Predicting the response of rock mass is important to ensure that gas leakage due to rupture of the steel lining does not occur.Analytical and numerical models can be used to estimate the rock mass response to high internal pressure;however,the fitness of these models under different in situ stress conditions and cavern shapes has not been studied.In this paper,the suitability of analytical and numerical models to estimate the maximum cavern wall tangential strain under high internal pressure is studied.The analytical model is derived in detail and finite element(FE)models considering both two-dimensional(2D)and three-dimensional(3D)geometries are presented.These models are verified with field measurements from the LRC in Skallen,southwestern Sweden.The analytical model is inexpensive to implement and gives good results for isotropic in situ stress conditions and large cavern heights.For the case of anisotropic horizontal in situ stresses,as the conditions in Skallen,the 3D FE model is the best approach.

On the Characteristics of Coaxial-Type Microwave Excited Linear Plasma:a Simple Numerical Analysis

To unveil the characteristics and available propagation mechanism of coaxial-type microwave excited line-shape plasma, the effects of parameters including microwave power, working pressure, dielectric constant, and external magnetic field on the plasma distribution were numerically investigated by solving a coupled system of Maxwell＇s equations and continuity equations. Numerical results indicate that high microwave power, relatively high working pressure, low dielectric constant, and shaped magnetic field profiles will help produce a high-density and uniform plasma source. Exciting both ends by microwave contributed to the high-density and uni- form plasma source as well. Possible mechanisms were analyzed by using the polarization model of low temperature plasma. The generation and propagation processes of the line-shape plasma mainly depend on the interaction of three aspects, i.e. the transmitted part, penetration part and absorptive part of the electromagnetic field. The numerical results were qualitatively consistent with available experimental results from literature. More elaborate descriptions of the three aspects and corresponding interactions among them need to be investigated further to improve the properties of the line-shape plasma.

Analysis of QTLs for Flag Leaf Shape and Its Response to Elevated CO_2 in Rice(Oryza sativa)

To understand the responses of flag leaf shape in rice to elevated CO2 environment and their genetic characteristics, quantitative trait loci （QTLs） for flag leaf shape in rice were mapped onto the molecular marker linkage map of chromosome segment substitution lines （CSSLs） derived from a cross between a japonica variety Asominori and an indica variety IR24 under free air carbon dioxide enrichment （FACE, 200 μmol/mol above current levels） and current CO2 concentration （Ambient, about 370 μmol/mol）. Three flag-leaf traits, flag-leaf length （LL）, width （LW） and the ratio of LL to LW （RLW）, were estimated for each CSSL and their parental varieties. The differences in LL, LW and RLW between parents and in LL and LW within IR24 between FACE and Ambient were significant at 1% level. The continuous distributions and transgressive segregations of LL, LW and RLW were also observed in CSSL population, showing that the three traits were quantitatively inherited under both FACE and Ambient. A total of 16 QTLs for the three traits were detected on chromosomes 1, 2, 3, 4, 6, 8 and 11 with LOD （Log10-1ikelihood ratio） scores ranging from 3.0 to 6.7. Among them, four QTLs （qLL-6＊, qLL-8＊ qLW-4＊ and qRLW-6＊） were commonly detected under both FACE and Ambient. Therefore, based on the different responses to elevated CO2 in comparison with current CO2 level, it can be suggested that the expressions of several QTLs associated with flag-leaf shape in rice could be induced by the high CO2 level.

Second-order phase correction of NMR spectra acquired using linear frequency-sweeps

NMR spectra acquired with experiments using frequency-sweeps such as the wide-band uniform-rate smooth truncation(WURST)spin-echo and Carr-Purcell-Meiboom-Gill(CPMG)sequences cannot be absorptively phased by using only conventional zerothand first-order phase correction.Implementation of phase correction up to the secondorder is described for obtaining absorptive spectra,which have more desirable line shapes and noise properties than magnitude spectra.The relationship of the second-order phase to the parameters of frequency sweeps is derived.The second-order phasing in the frequency-domain is equivalent to a point spread in the time-domain signal.The application of second-order phase correction is demonstrated with a wideline 35Cl CPMG spikelet spectrum.

稳定表达H7N9亚型禽流感病毒HA蛋白的293T细胞株构建及应用

为获得用于评价H7N9亚型禽流感疫苗诱导的抗体Fc免疫效应的靶细胞,研究采用慢病毒包装与感染技术构建一株稳定表达H7N9亚型禽流感病毒(H7N9 AIV)HA蛋白的细胞株,并以该细胞株为靶细胞建立H7N9亚型禽流感疫苗免疫血清补体介导的细胞毒(ADCML)活性的检测方法。结果显示成功包装了一株重组慢病毒,滴度可达108 FU/mL;构建了稳定表达H7N9 AIV HA蛋白的293T细胞株,HA蛋白主要在细胞膜上表达。基于新城疫病毒(NDV)载体的H7N9亚型禽流感疫苗免疫鸡后,诱导产生的HA结合性IgG抗体滴度为2180。以稳定细胞株为靶细胞,载体疫苗血清诱导的细胞死亡水平显著高于空载体与未免疫鸡血清(P<0.001);补体灭活后,载体疫苗血清诱导的细胞死亡水平显著降低(P<0.001)。研究表明,基于NDV载体的H7N9亚型禽流感疫苗免疫鸡血清具有较强的ADCML活性,稳定表达H7N9 AIV HA蛋白的细胞株可作为评价H7N9亚型禽流感疫苗免疫血清Fc免疫效应的靶细胞。

c-Ha-ras and c-myc antisense oligodeoxynucleotides inhibit the proliferation and DNA synthesis in human gastric carcinoma cell lines

The effects of two antisense oligodeoxynucleotides on the expression of c-Ha-ras proto-oncogene and the growth of human gastric carcinoma cell lines were observed. Synthetic 15-mer directed at the region of the translational initiation site of c-Ha-ras proto-oncogene (ASO-r) greatly inhibited the proliferation (55. 61%,P<0. 05) and DNA synthesis (76. 79%,P<0. 05) of MGc-803 cell line. It also inhibited the proliferation (62. 02%,P<0. 05) and DNA synthesis (76. 78%, P<0. 05) of SGc-7901 cell line. A reduction in intracellular P21 ras protein levels in MGc-803 cell line was observed 6 h after the treatment with ASO-r and maintained over 12 h. Another synthetic 15-mer targeted against the initiation codon and downstream 4 codons of c-myc proto-oncogene (ASOm) inhibited only DNA synthesis of MGc-803 cell line (71. 37%, P<0. 05). The control 15-mer did not inhibit the expression of P21 protein and proliferation of these cell lines. These experiments seemed to provide evidence that ASO-r could be effective in inhibiting the expression of c-Ha-ras proto-oncogene and controlling the growth of human gastric carcinoma cells,and that the over-expression of c-Ha-ras proto-oncogene might mainly be associated with the malignant proliferation of human gastric carcinoma cells.

基于轨迹线改进的临界多边形算法

在异形件的下料排样问题中,最为困难的就是求解裁片在板料中的位置以保证材料较高的利用率,算法复杂度随着料片数量和料片轮廓复杂度的增加迅速上升。临界多边形算法是计算异形件之间靠接位置和重叠关系的一种基础性几何工具,临界多边形算法的性能与下料排样算法效率密切相关。本文在基于轨迹线的求解临界多边形算法基础上,提出一种求解临界多边形(NFP)的改进算法。该算法有效地将移动碰撞算法和轨迹线算法相结合,充分发挥两类算法各自的优点,提高了临界多边形求解的计算速度。仿真实例验证了改进方法的正确性和有效性。

局部外形参数对高速飞行器的RCS影响

为了降低高速飞行器的雷达散射截面(radar cross section,RCS),采用多层快速多极子算法和物理光学法研究局部外形参数对飞行器雷达散射特性的影响。在此基础上,提出一种变半径弧形的边缘钝化形式,以提高飞行器仰视对抗能力。所提出的变半径弧形钝化外形具有良好的RCS减缩能力,与传统圆弧钝化外形相比,在前向重点角域内,RCS对数均值降低了22.88%;随着仰角的增大,变半径弧形钝化形式还具备全向RCS减缩能力,在全向角域内RCS对数均值降低了13.37%。最后,研究所提出的变半径弧形钝化方式在不同雷达波频段下的RCS特性,结果表明这种钝化方式对于频率较高时仰视对抗能力更好。

工位数固定的U型拆卸线部分拆卸平衡问题

为提高工位数固定的U型拆卸线拆卸效率,减少有害部件对操作人员的潜在威胁,针对高价值零部件和有害零部件的拆卸需求,本文提出了工位数固定的U型拆卸线部分拆卸平衡问题,建立了以最小化节拍时间、高危工位数目和负载均衡为目标的优化模型,并设计了改进的变邻域搜索算法进行求解.在编码过程中提出一种基于零部件释放位置的选择策略,以减少前继零部件拆卸顺序对编码的影响;提出最小偏差二分法,有效减少解码的迭代次数;提出瓶颈挤压局部搜索策略,用以优化节拍时间和均衡负载指标.通过与其他算法对比,结果表明改进的变邻域搜索算法求解具有优越性,并且可实现对工位数固定的U型拆卸线部分拆卸平衡问题的高效求解.

镂空重构手法在服装设计中的创新应用

为了打破镂空工艺对材料、技术的使用界限,丰富其在服装设计中的创新应用,通过梳理服装中镂空构型的起源与发展,在镂空重构概念界定的基础上,结合已有案例归纳分析镂空重构的3类实现手法:连接点式镂空、重塑线式镂空以及剪切面式镂空。以连接点式镂空手法为例,进一步探究镂空重构手法在服装设计中的创新实践:一是镂空构型材料层面的创新,将环保理念融入服装设计,实现废弃物升级利用;二是造型表现技术层面的创新,结合立体塑形进行服装造型表现的拓展实践,并对镂空重构手法在服装设计领域的应用前景作了展望。

广义多边形凸包弹性线递支模拟算法

针对诸多领域涉及的平面弯曲图形的凸包计算,提出弹性线递支模拟算法用于计算简单闭广义多边形的弹性包络线。所提算法基于物理模型,通过判断各支点是否受力平衡来判别其是否为弹性包络线上的平衡支点,并据此分别进行前进、回弹和跳跃等操作,直至计算出所有平衡支点进而求出其弹性包络线。3种典型的简单闭广义多边形的对比测算表明:所提算法可实时稳健地求解平面任意简单闭广义多边形的弹性包络线,具有高效性和普遍适用性。

NiTi表面电化学方法制备HA生物涂层的工艺研究

系统研究了 NiTi 形状记忆合金表面电化学方法制备 HA 生物涂层过程中工艺参数对涂层相组成及其结构和形貌的影响,得出了最佳沉积规范,在该规范下沉积的涂层均由 CaHPO4·2H2O 组成,经碱处理后完全转变为 HA。所制备的 HA 涂层均匀致密,一定条件下涂层形貌由传统的针状转变为片层状。初步探讨了 HA 涂层形貌发生转变的机理。