一种基于色差的彩色图像的边缘检测方法

传统的边缘检测方法大都是基于灰度图像的,这就不能充分利用彩色图像的全部信息。文章提出了一种基于色差的彩色图像的边缘检测方法,它能快速准确地检测到图像的边缘,具有低的错判率和较高的效率,优于传统基于灰度的边缘检测方法。     

Stabilization of positive coupled differential‐difference equations with unbounded time‐varying delays

This paper researches the static output‐feedback stabilization of single‐input single‐output (SISO) positive coupled differential‐difference equations (CDDEs) with unbounded time‐varying delays. First, a necessary and sufficient condition is provided for the positivity and asymptotical stability of CDDEs with unbounded time‐varying delays. For this type of system, based on the constructed estimates of its solution, a necessary and sufficient condition on asymptotical stability is provided. Then, based on this criterion, for CDDEs with unbounded time‐varying delays, a kind of static output‐feedback controller is designed to ensure the positivity and asymptotical stability of the corresponding closed‐loop systems. It is also worth pointing out that the controller is designed by the linear programming method without parameterization technique. This design approach can also be applied to the static state feedback stabilization problem of CDDEs with unbounded time‐varying delays. Finally, two illustrative examples are given to show the effectiveness of our results.     

Adaptive Order WENO Reconstructions for the Semi-Lagrangian Finite Difference Scheme for Advection Problem

We present a new conservative semi-Lagrangian finite difference weighted essentially non-oscillatory scheme with adaptive order. This is an extension of the conservative semi-Lagrangian (SL) finite difference WENO scheme in [Qiu and Shu, JCP, 230 (4) (2011), pp. 863-889], in which linear weights in SL WENO framework were shown not to exist for variable coefficient problems. Hence, the order of accuracy is not optimal from reconstruction stencils. In this paper, we incorporate a recent WENO adaptive order (AO) technique [Balsara et al., JCP, 326 (2016), pp. 780-804] to the SL WENO framework. The new scheme can achieve an optimal high order of accuracy, while maintaining the properties of mass conservation and non-oscillatory capture of solutions from the original SL WENO. The positivity-preserving limiter is further applied to ensure the positivity of solutions. Finally, the scheme is applied to high dimensional problems by a fourth-order dimensional splitting. We demonstrate the effectiveness of the new scheme by extensive numerical tests on linear advection equations, the Vlasov-Poisson system, the guiding center Vlasov model as well as the incompressible Euler equations.     

艺术大学生自我效能、主观幸福感及其关系的研究

目的研究艺术大学生自我产能与主观幸福感的关系。方法用幸福感指数量表、一般自我效能感量表494艺术大学生进行了测量。结果①艺术大学生的主观幸福感和自我效能感有显着的独生和性别差异。②艺术大学生的高、低自我效能与主观幸福感存在显着的差异和相关。结论自我效能是影响幸福感的重要因素。     

Strain-dependent effects of post-training GABA receptor agonists and antagonists on memory storage in mice

Post-training administration of the GABA-A and GABA-B receptor agonists muscimol and baclofen dose-dependently impaired retention of an inhibitory avoidance response in C57 mice, while improving memory consolidation in the DBA strain. By contrast, picrotoxin (blocker of GABA-activated ionophores), bicuculline (GABA-A antagonist) and CGP 35348 (GABA-B antagonist) dose-dependently improved retention in C57 mice and impaired it in DBA mice. These effects cannot be ascribed to non-specific actions of the drugs on retention performance, as the latencies during the retention test of those mice that had not received footshock during the training were not lengthened by the post-training drug administration. The effects on retention performance induced by GABA agonists and antagonists are probably due to an effect on memory consolidation, since they are observed when the drugs are given at short, but not at long, intervals after training. These results are discussed in terms of possible interaction of GABA systems with endogenous opioid and dopamine systems, whose activation has been shown to produce strain-dependent effects on memory processes. The possible utilization of these results for a genetic behavioral approach with recombinant inbred (RI) mice is also considered.     

胎粪吸入综合征患儿肾血流动力学的改变

目的：探索新生儿窒息并发胎粪吸入综合征（meconium aspiration syndrome,MAS）时肾血流动力学的改变。方法：应用彩色超声血流显像技术,对窒息合并MAS的新生儿的肾动脉血流参数及心输出量进行检测。结果：并发MAS的窒息儿肾动脉血流速度和血流量降低,但阻力无改变;心输出量降低;肾血流量与心输出量的比值也降低。结论：并发MAS的窒息儿,其肾脏损害加重,早期检测肾血流动力学变化,早期发现肾功改变并指导治疗。     

Nationality differences in distributions of serum lipids, lipoproteins and apolipoproteins levels in Xinjiang China

目的　种族间血脂水平的差异已有研究。本文拟探讨民族间血脂、脂蛋白及载脂蛋白水平是否也存在差异。方法　作者对新疆地区的汉族居民 911人 (男性 4 6 6人 ,女性 4 45人 )及哈萨克族居民 773人 (男性 36 0人 ,女性4 13人 )随机个体血总胆固醇 (TC)、甘油三酯 (TG)、高密度脂蛋白胆固醇 (HDL c)、低密度脂蛋白胆固醇 (LDL c)、脂蛋白 (a) (Lp(a) )及载脂蛋白A1(ApoA1)、载脂蛋白B(ApoB)进行测定。结果　与汉族人群比较 ,哈萨克族人群男、女均分别有较高的HDL c(P <0 0 0 1)和ApoA1(P <0 0 0 1)水平与较低的TG(P <0 0 1,P <0 0 0 1)、Lp(a) (P <0 0 0 5 )、ApoB(P <0 0 0 5 ,P <0 0 0 1)及较低的ApoB/ApoA1值 (P <0 0 1,P<0 0 0 1) ;汉族人群有 2 0 7%的个体ApoA1水平值低于 1 2g/L ,而在哈萨克族人群中只有 9 8%的个体ApoA1值低于 1 2g/L ,汉族人群有 18 6 %的个值ApoB值高于 1 2g/L ,而在哈萨克族人群中只有 14 3%的个体ApoB水平值超过 1 2g/L ;多因素相关与回归分析发现 :TG、HDL c、Lp(a)、ApoAI及ApoB/ApoAI值水平均与民族有密切的相关关系。结论　血脂、Lp(a)、ApoA1及ApoB水平存在显著的民族间的差异 ,哈萨克族人群具有较汉族人群明显为优的血脂谱 ,推测遗传因素可能控制和影响着个体     

应用彩色多普勒超声诊断结节性甲状腺病变

目的 探讨彩色多普勒超声鉴别诊断结节性甲状腺病变的意义。方法 回顾性分析病理或细胞学证实的结节性甲状腺病变74例二维超声和彩色多普勒超声（CDFI）表现。结果 结节性甲状腺肿、甲状腺腺瘤和腺癌超声和血流图像表现有一定规律性,定位准确,敏感性强。结论 彩色多普勒超声是诊断结节性甲状腺病变首选检查方法。     

二维彩色多普勒对左心扩大疾病瓣膜返流的半定量研究

目的 :研究左心扩大性疾病瓣膜返流情况、心腔形态学改变以及心功能的变化。方法 :利用二维及M型超声心动图测量各房室腔大小 ,用机内软件及脉冲多普勒频谱评价心功能 ,应用彩色多普勒技术记录各瓣口返流血束 ,根据返流束的长短估测返流程度。结果 :每组病例均有多瓣口返流现象 ,但以扩张型心肌病 (DCM)组发生率高且程度重 ,DCM以二尖瓣返流 (MR)为主 ( 91% ) ,中重度占 60 % ;缺血性心肌病 (ICM)以MR、主动脉瓣返流 (AR)为主 (分别为 75 %和 70 % ) ,左心衰组返流较轻。 3组病例的平均左房、左室以及合并中重度MR、AR的左房、左室均显著扩大 (P <0 .0 0 1) ,平均值与合并中重度返流的测值之间无显著性差异。DCM组以收缩功能下降为主 ( 70 % ) ,ICM组以舒张功能下降为主 ( 75 % )。结论 :左心腔扩大性疾病可通过瓣膜返流的半定量研究以及合并心功能异常情况为临床诊断及治疗提供有益的依据     

彩色多普勒能量图对不孕症妇女子宫动脉血流变化的观察

利用彩色多普勒能量图测定子宫的血流 ,即血流的脉冲指数 (pulsative index,PI)及阻力指数 (resistantindex,RI)来探索不同原因的女性不孕症。 6 7例不孕症妇女经腹腔镜诊断确诊不孕原因后 ,于月经周期第 2 0～ 2 3d作腹部 B超彩色多普勒能量图 (CDE)检查。其结果两侧子宫动脉 PI、RI可因各种不孕原因不分侧别平均 PI、RI均高于正常组 (P<0 .0 1) ,而且不受病情轻、中、重所影响。反映了子宫周围血管阻力较高所致子宫动脉血流灌注不足是引起不孕症的基础 ,可能也干扰孕卵着床而致不孕。