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81.
The 22q11.2 deletion syndrome (velocardiofacial/DiGeorge syndrome)is a neurogenetic condition associated with visuospatial deficits,as well as elevated rates of attentional disturbance, mood disorder,and psychosis. Previously, we detected pronounced cortical thinningin superior parietal and right parieto-occipital cortices inpatients with this syndrome, regions critical for visuospatialprocessing. Here we applied cortical pattern-matching algorithmsto structural magnetic resonance images obtained from 21 childrenwith confirmed 22q11.2 deletions (ages 8–17) and 13 demographicallymatched comparison subjects, in order to map cortical thicknessacross the medial hemispheric surfaces. In addition, corticalmodels were remeshed in frequency space to compute their surfacecomplexity. Cortical maps revealed a pattern of localized thinningin the ventromedial occipital–temporal cortex, criticalfor visuospatial representation, and the anterior cingulate,a key area for attentional control. However, children with 22q11.2DSshowed significantly increased gyral complexity bilaterallyin occipital cortex. Regional gray matter volumes, particularlyin medial frontal cortex, were strongly correlated with bothverbal and nonverbal cognitive functions. These findings suggestthat aberrant parieto-occipital brain development, as evidencedby both increased complexity and cortical thinning in theseregions, may be a neural substrate for the deficits in visuospatialand numerical understanding characteristic of this syndrome.  相似文献   
82.
Objective: To develop a model of the problems of persons with traumatic brain injury that includes multiple perspectives as well as the multi-dimensional nature of the phenomena.

Design: Concept mapping, a multi-variate modelling strategy, was employed to produce an exhaustive inventory and concept map of TBI-related problems based on input from patients, family caregivers and professional providers.

Results: The eight-cluster concept map included the following dimensions: social competence, intimacy, behavioural, maturity/independence, neurophysiological, mood, executive functions and non-executive functions.

Conclusions: An underlying two-dimensional conceptual model of TBI problems is proposed with relevance for theory, practice and further research.  相似文献   
83.
提出了一种快速曲面纹理合成技术,算法首先从样本纹理中裁剪三个菱形块,然后拼合成一个三角块,并用优化算法消除三角块内部的接缝,得到一个可拼接的三角纹理块--Triangle Tile.通过菱形块随机组合,可生成一系列这样的TriangIe Tiles.选取合适的Triangle Tile,逐个映射到三角网格上,从而完成曲面纹理合成.由于Triangle Tiles 是事先离线制作,因此算法合成速度很快,达到了实时性.  相似文献   
84.
A restriction map has been constructed for Anastrepha suspensa mitochondrial DNA. One HaeIII site was found to be polymorphic among individuals in highly inbred colonies and a feral population. Based on mapping information, the polymorphic site was determined to be in the ATPase 6 gene. Primers TK-J-3804 and C3-N-5460 amplified this region. The amplicon was cut by HaeIII in flies of one haplotype and not cut in flies of the other haplotype. From 30 to 43% of the individual flies studied had this additional HaeIII site. After cloning of the 5200 bp XbaI fragment, the two mitotypes were identified. A 988 base fragment, coding for the entire tRNA-Lys(AAG), tRNA-Asp(GAC), and ATPase 8genes, and a partial ATPase 6gene was sequenced Four silent mutations, including the one at the informative site were located. The HaeIII polymorphism and other sequence differences may prove useful as a diagnostic for identification of the origin of introduced fruitflies.  相似文献   
85.
Internal preference mapping (IPM) and Landscape Segmentation Analysis® (LSA) are two techniques broadly used to unfold consumers’ overall product liking ratings and create spatial maps that will provide further insights on consumers’ preferences. IPM is based on a vector model while LSA involves an ideal point model. Through a simulation and the analysis of 27 market research data sets, it is shown that IPM consistently creates a hedonic dimension that prevents the identification of satiety prone attributes (intensities higher or lower than a optimal level being disliked by the consumers) on that dimension. As a result, subsequent steps taken upon generating an IPM map such as the investigation of drivers of liking, population segmentation and the estimation of optimal product profiles have also a strong likelihood of resulting in distorted results, the level of distortion being dependent on the actual configuration of the underlying structure that IPM tried to uncover. It is also shown that a technique based on ideal points such as LSA does not exhibit this systematic artifact when unfolding liking data. Consequently, sensory scientists and market researchers should use caution when interpreting and using results issued from an internal preference mapping analysis.  相似文献   
86.
分析指出,隐喻是源域事物的部分特征向目标域映射的结果,颜色是最常见的隐喻源之一。通过对比分析英汉语言中的"黑色"的隐喻映射普遍性与差异性,有利于揭示产生二者异同的民族文化心理动因。  相似文献   
87.
采用非线性映射分析方法对区域城市化水平进行了聚类分析.结果表明,非线性映射方法通过对高维样本进行降维处理,使不同城市化水平等级的城市得以清晰地划分,结果直观形象地显示在二维平面中,从而实现了水平近似城市的聚类,克服了以往系统聚类分析法所得结果不够直观、存在虚假归并等问题,为城市化水平的定量判定提供了一种新方法.  相似文献   
88.
研究映射对与映射族的公共不动点问题,得到一系列结论。  相似文献   
89.
进行大豆蛋白质含量相关的QTL定位可为分子标记辅助选择(MAS)育种和基因挖掘提供依据。本研究选用综合性状优良、蛋白质含量高的中黄13作轮回亲本,低蛋白质含量的东山69作供体亲本,构建了BC2F2、BC2F3回交导入系群体,采用SSR分子标记技术,获得含86个SSR标记、覆盖1 400.1cM、由19个连锁群组成的遗传连锁图谱a,利用完备区间作图法(ICIM),对BC2F2、BC2F3分离群体的蛋白质含量进行QTL分析。结果表明:在BC2F2家系中检测到3个蛋白质含量相关QTL,分布于A1、C1和J连锁群,表型贡献率分别为10.00%、7.07% 和9.23%;在BC2F3家系中检测到4个蛋白含量相关QTL,分布于B1、C1、I和J连锁群,表型贡献率分别为17.57%、3.46%、8.53%和11.80%。标记区间Satt396~Satt180和Sct_001~Satt654在BC2F2、BC2F3家系中被同时检测到,且Sct_001~Satt654内发现的QTL很可能是一个与蛋白质含量相关的新位点。  相似文献   
90.
三维虚拟展示技术能够较好地模拟织物穿着后所表现的外观及悬垂性、光泽、褶皱等物理性能,更好地服务于个性化私人订制.现有的纺织面料虚拟展示系统侧重于二维平面的展示,缺乏对面料最终效果进行立体三维全方位的虚拟展示.使用3DMAX和OpenGL图形库以及一些辅助工具,通过设计系统功能和操作界面、搭建应用场景、三维人体服装建模、...  相似文献   
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