黄花菜V脊菱蜡蝉成虫趋光性测定

利用成虫的趋光性，连续2a采用频振杀虫灯与普通白炽灯进行了对照观察，结果表明：黄花菜V脊菱蜡蝉成虫对频振杀虫灯和白炽灯均有较强的趋性。频振杀虫灯日平均诱虫量4．5只，白炽灯日平均诱虫量5．5只。每公顷安装1盏频振杀虫灯或普通白炽灯用于防治该害虫有积极的作用。     

Visualization of turbulent flame fronts with planar laser-induced fluorescence

This report concerns the quantitative time-resolved visualization of reaction zones in laminar, transitional, and turbulent nonpremixed flames. Two-dimensional OH molecular concentrations were measured with planar laser-induced fluorescence excited by a sheet of light (formed from a single tunable ultraviolet laser pulse) and detected with a two-dimensional, image-intensified photodiode array camera. From the resulting data details of instantaneous flame front structures (including positions, shapes, and widths) were obtained.     

Ferroin-collodion membranes: dynamic concentration patterns in planar membranes

Patterns and waves of the Belousov-Zhabotinskii reaction are produced in membranes in which one reactant is immobilized. Convection is eliminated, the generation and deformation of wave forms are studied, and patterns are permnanently fixed. Wave shape, frequency, length, and phase velocity are explained theoretically by the interactions of diffusion with reaction.     

闭链二自由度平面五杆机构运动分析

应用矩阵法建立常用闭链二自由度平面五杆机构基本杆组运动分析数学模型,并据此编制相应的杆组位移、速度和加速度分析模块,开发了平面五杆机构的计算机辅助分析与仿真系统,实现了机构运动参数数值计算、运动线图自动绘制和机构动态仿真等计算机辅助可视化运动分析,所建立的数学模型与开发的程序具有较强的通用性．最后以机械系统动力学分析软件ADANS进行仿真,验证了机构运动分析数学模型及程序的正确性．     

Mathematical modeling of planar cell polarity to understand domineering nonautonomy

Planar cell polarity (PCP) signaling generates subcellular asymmetry along an axis orthogonal to the epithelial apical-basal axis. Through a poorly understood mechanism, cell clones that have mutations in some PCP signaling components, including some, but not all, alleles of the receptor frizzled, cause polarity disruptions of neighboring wild-type cells, a phenomenon referred to as domineering nonautonomy. Here, a contact-dependent signaling hypothesis, derived from experimental results, is shown by reaction-diffusion, partial differential equation modeling and simulation to fully reproduce PCP phenotypes, including domineering nonautonomy, in the Drosophila wing. The sufficiency of this model and the experimental validation of model predictions reveal how specific protein-protein interactions produce autonomy or domineering nonautonomy.     

Voltage-dependent calcium channels from Paramecium cilia incorporated into planar lipid bilayers

Two different divalent cation-selective channels from Paramecium cilia were incorporated into planar lipid bilayers. Both channels were much more permeable to divalent than univalent cations, and one of them discriminated significantly among the divalent cations. The selectivity and voltage dependence of the latter channel are comparable to those of voltage-dependent calcium channels found in a variety of cells. A combined biochemical, biophysical, and genetic study of calcium channels is now possible.     

平面立体轴测形态图计算理论和方法

以平面立体的投影图中出现的奇异性为基础 ,论述了平面立体所有视觉事件类型及其对应的投影空间的划分 ,指出平面立体的投影空间划分的关键是立体上两个不在同一多边形面上的顶点和棱线以及每三条空间相互交叉的棱线之间发生的奇异性 ,分析了三种类型分割平 (曲 )面 ,给出了平面立体形态图和特征视图的求解方法 ,并用实例进行了计算     

造林土质边坡浅层平面滑坡模型的初步研究

造林土质边坡容易发生浅层平面滑坡。基于极限平衡理论,综合考虑土质边坡上林木根系的力学加固土壤作用和水文增加基质吸力效应,以及林木附加自重对边坡稳定的负面效应,建立了一个用来评价造林土质边坡浅层平面滑坡的分析模型。所有模型参数中土壤内摩擦角和边坡坡度的微弱变化能引起边坡安全系数较大浮动,而林木附加自重的变化对安全系数的影响较小。造林土质边坡浅层滑坡分析模型中林木根系对土壤的力学加固作用采用了修正的植物根系提高土壤抗剪强度的简单力学增强模型,相比以往类似边坡稳定性模型,分析模型显著提高了预测边坡稳定的准确性。      

Direct observations of structural phase transitions in planar crystallized ion plasmas

Laser-cooled 9Be+ ions confined in two-dimensionally extended lattice planes were directly observed, and the images were used to characterize the structural phases of the ions. Five different stable crystalline phases were observed, and the energetically favored structure could be sensitively tuned by changing the areal density of the confined ions. The experimental results are in good agreement with theoretical predictions for the planar (infinite in two dimensions) one-component plasma. Qualitatively similar structural phase transitions occur, or are predicted to occur, in other experimentally realizable planar systems.     

单一平面电容传感器数学模型的数值解法

单一平面电容传感器是用来测量木材含水率的高精度仪器,属于具有任意结构形状的电容传 感器的特例。为研究单一平面传感器数学模型的数值解法,以一种设定了具体尺寸的单一平面电容传感器为例,利用数值分析的一个数值方法——差分离散格式,对笔者前期建立 的任意结构形状的电容传感器的偏微分方程数学模型构造了便于计算和研究的离散近似模型。利用该近似模型对单一平面电容传感器的工作状况进行分析,得到了木材介电常数与传感器电容值的关系。      

基于高副低代方法的平面凸轮设计

基于高副低代原理，将平面凸轮机构代换为平面连杆机构，运用圆向量函数建立代换机构的位移、速度、加速度矢量方程式，通过计算虚拟连杆的杆长和方向，求得凸轮实际廓线、曲率半径和压力角的表达式。并给出用圆形刀具加工凸轮时刀具中心的轨迹方程。运用该方法详细分析了滚子直动和滚子摆动从动件盘形凸轮机构中的凸轮设计问题，并对平面凸轮进行了设计，结果表明，该方法正确可行。     

鸭嘴式穴播器活动门凸轮-平面四杆式开启机构的研究

鸭嘴式成穴器的活动嘴开启机构是影响成穴器性能的主要因素之一.为了克服传统启闭机构容易失灵的缺点,本试验中研制了一种凸轮-平面四杆式开启机构,并确定了该凸轮-平面四杆式开启机构的关键参数.     

Mechanical control of morphogenesis by Fat/Dachsous/Four-jointed planar cell polarity pathway

During animal development, several planar cell polarity (PCP) pathways control tissue shape by coordinating collective cell behavior. Here, we characterize by means of multiscale imaging epithelium morphogenesis in the Drosophila dorsal thorax and show how the Fat/Dachsous/Four-jointed PCP pathway controls morphogenesis. We found that the proto-cadherin Dachsous is polarized within a domain of its tissue-wide expression gradient. Furthermore, Dachsous polarizes the myosin Dachs, which in turn promotes anisotropy of junction tension. By combining physical modeling with quantitative image analyses, we determined that this tension anisotropy defines the pattern of local tissue contraction that contributes to shaping the epithelium mainly via oriented cell rearrangements. Our results establish how tissue planar polarization coordinates the local changes of cell mechanical properties to control tissue morphogenesis.     

SPECT断层显像和平面显像测算甲状腺重量准确性的比较

目的 :对比分析SPECT断层显像和平面显像测算Graves’病患者甲状腺重量的准确性。方法 :行手术切除甲状腺的 32例Graves’病患者利用甲状腺SPECT断层显像及平面显像分别测算手术前后甲状腺重量差值 ,与手术切除标本实际重量相比较。另对 2 82例Graves’病患者用两种显像方法测算甲状腺重量进行对比分析。结果 :手术前后断层显像测算的甲状腺重量差值与手术切除标本实际重量的差异无显著性 (P >0 .0 5 ) ,而平面显像测算的差值大于切除标本实际重量 ,差异有显著性t=7.5 4 9,P <0 .0 1)。 2 82例的对比结果表明甲状腺厚径的不同对测算结果有影响。结论 :测算甲状腺重量时 ,SPECT平面显像因缺乏厚径信息而误差较大 ,断层显像更为准确 ,在13 1Ⅰ治疗Graves’病确定剂量时更有意义。     

Osmotic swelling of phospholipid vesicles causes them to fuse with a planar phospholipid bilayer membrane

Fusion of phospholipid vesicles with planar bilayer membranes occurs if the vesicles that contact the planar membrane swell osmotically after the replacement in their medium of an impermeant solute by a permeant one. This finding directly demonstrates that osmotic swelling is a driving force for vesicle-planar membrane fusion. The method used to induce vesicle swelling and fusion may have relevance for biological systems.     

Calcium channels in planar lipid bilayers: insights into mechanisms of ion permeation and gating

Electrophysiological recordings were used to analyze single calcium channels in planar lipid bilayers after membranes from bovine cardiac sarcolemmal vesicles had been incorporated into the bilayer. In these cell-free conditions, channels in the bilayer showed unitary barium or calcium conductances, gating kinetics, and pharmacological responses that were similar to dihydropyridine-sensitive calcium channels in intact cells. The open channel current varied in a nonlinear manner with voltage under asymmetric (that is, physiological) ionic conditions. However, with identical solutions on both sides of the bilayer, the current-voltage relation was linear. In matched experiments, calcium channels from skeletal muscle T-tubules differed significantly from cardiac calcium channels in their conductance properties and gating kinetics.