Classification problems for shifts on modules over a principal ideal domain

In this paper we study symbolic dynamics over alphabets which are modules over a principal ideal domain, considering topological shifts which are also submodules. Our main result is the classification, up to algebraic and topological conjugacy, of the torsion-free, transitive, finite memory shifts.

     

多心理账户下机构投资者的风险优化研究

从决策有限理性角度，引入行为金融理论于机构投资风险优化系统，对多心理账户条件下机构投资的风险优化设计进行了研究。以Friedman和Savage之谜为释例，对机构投资风险优化中的诸多非标准金融异像进行了解释。以Shefrin和Statman行为证券组合理论为核心，建立了多心理账户条件下机构投资的风险优化模型，为机构投资的风险优化实践提供了一种量化分析工具。     

对期望理论的两个重要推进——损失厌恶系数λ及参考点研究

行为金融学是近20年来最为重要的新兴金融理论,期望理论更是其中的亮点,其运用领域之广超乎人们的想象,所以对它的完善改进具有非常重要的意义。本文对期望理论中的损失厌恶系数和参考点问题进行了深入研究,并且得出了创新性的结果:损失厌恶系数不是常数而是动态变量;得出了内生且纳入更多投资者行为特征的参考点。这些结果是对期望理论的重要改善和推进,对其在大量金融领域和涉及到财富偏好的问题的解决中都大有裨益。     

一种面向测试的RTL行为抽象与蕴含方法

针对寄存器传输级（register transfer level,RTL)行为的抽象，提出了一种层次化的带条件的表示，这种抽象的行为是面向测试的，它不仅表达简单，而且能很方便地进行蕴含操作，通过抽象，电路可以规范为行为集，并代替电路本身进行功能测试向量的生成，在测试生成过程中，大量地应用蕴含操作何以使其中的行为得到简化，并极大地提高了系统的效率。     

布依族7项不对称行为特征的研究

对布依族的7项不对称行为特征(利手、扣手、叠臂、叠腿、利足、起步和利眼)进行了调查，结果显示：(1)7项指标在布依族中的出现率R型(右型)远高于L型(左型)；(2)布依族中7项指标出现率均无性别间差异；(3)与蒙古族、朝鲜族、汉族、鄂温克族、鄂伦春族、达斡尔族、汉族等民族作比较，发现布依族各项指标L型出现率偏低，且扣手、叠臂、起步L型出现率和这6个民族存在极显著性差异，叠腿L型出现率除与鄂伦春族无差异外，与另外5个民族均有极显著性差异，其他指标与这6个民族基本不存在差异；(4)布依族扣手基因频率(％)为：A=0．1653，a=0．8347；布依族利手基因频率为：B=0．6990，b=0．3010；(5)统计分析了7项指标间的相关性，发现多数指标间存在相关性，部分指标相关极显著，且R—R型组合(右型一右型)的出现频率远高于L—L型组合(左型一左型)的出现频率．     

公司股利政策研究综述——兼论股利政策的行为假说及进展

在对以往研究进行梳理的基础上，重点考察了股利政策行为假说的研究及进展，并指出利用行为经济学、行为金融学的理论与方法重新构建财务理论（包括股利政策）是未来重要的研究方向。     

现代投资组合理论模型的比较研究

对证券组合理论的Markowitz均值-方差模型以及均衡时关于资产的期望收益率的资本资产定价模型（CAPM）和套利定价理论（APT），进行了深入地比较研究，同时从动态投资组合理论，基于VaR的投资组合理论以及行为投资组合理论三个领域阐述了现代投资组合理论的新进展，并对其未来的发展进行了展望。     

行为金融论介

行为金融理论是自20世纪80年代兴起的金融学说，目前这一学说是西方国家金融研究和实践的前沿领域，同时也是热门领域。在综合国外研究成果的基础上．从行为金融与传统金融的联系与区别入手，对该理论进行了详细的论述，最后对其未来的发展趋势进行了展望。     

Contralaterally transplanted human embryonic stem cell-derived neural precursor cells (ENStem-A) migrate and improve brain functions in stroke-damaged rats

The transplantation of neural precursor cells (NPCs) is known to be a promising approach to ameliorating behavioral deficits after stroke in a rodent model of middle cerebral artery occlusion (MCAo). Previous studies have shown that transplanted NPCs migrate toward the infarct region, survive and differentiate into mature neurons to some extent. However, the spatiotemporal dynamics of NPC migration following transplantation into stroke animals have yet to be elucidated. In this study, we investigated the fates of human embryonic stem cell (hESC)-derived NPCs (ENStem-A) for 8 weeks following transplantation into the side contralateral to the infarct region using 7.0T animal magnetic resonance imaging (MRI). T2- and T2*-weighted MRI analyses indicated that the migrating cells were clearly detectable at the infarct boundary zone by 1 week, and the intensity of the MRI signals robustly increased within 4 weeks after transplantation. Afterwards, the signals were slightly increased or unchanged. At 8 weeks, we performed Prussian blue staining and immunohistochemical staining using human-specific markers, and found that high percentages of transplanted cells migrated to the infarct boundary. Most of these cells were CXCR4-positive. We also observed that the migrating cells expressed markers for various stages of neural differentiation, including Nestin, Tuj1, NeuN, TH, DARPP-32 and SV38, indicating that the transplanted cells may partially contribute to the reconstruction of the damaged neural tissues after stroke. Interestingly, we found that the extent of gliosis (glial fibrillary acidic protein-positive cells) and apoptosis (TUNEL-positive cells) were significantly decreased in the cell-transplanted group, suggesting that hESC-NPCs have a positive role in reducing glia scar formation and cell death after stroke. No tumors formed in our study. We also performed various behavioral tests, including rotarod, stepping and modified neurological severity score tests, and found that the transplanted animals exhibited significant improvements in sensorimotor functions during the 8 weeks after transplantation. Taken together, these results strongly suggest that hESC-NPCs have the capacity to migrate to the infarct region, form neural tissues efficiently and contribute to behavioral recovery in a rodent model of ischemic stroke.     

Behavioral Characteristics of Children With Vocal Fold Nodules

Vocal fold nodules (VNs) in children are benign, bilateral lesions occurring on the mid-membranous vocal folds. Repetitive phonotraumatic behavior leading to chronic vocal fold injury and repair is frequently cited as the primary etiology; however, specific behavioral characteristics may predispose some children toward intense and potentially phonotraumatic voice use, thereby contributing secondarily to VN formation. The purpose of this case-control study was to determine whether children with VNs possess unique behavioral characteristics that may predispose them to VN development. Parents of 26 children with VNs (20 boys, 6 girls, mean age=7.2 years, SD=2.5 years), and 29 vocally normal, medical controls (22 boys, 7 girls, mean age=6.7 years, SD=2.4), completed the Childhood Behavior Checklist (CBCL/4-18, Achenbach, 1991), a standardized parent-rating scale with strong psychometric properties. No significant between-group differences were detected on any of the behavior problem syndrome scales. Group differences approached significance for the individual items "screams a lot" and "teases a lot" (VN group > Controls). The VN group scored significantly higher than the controls on the "Social Scale," a compilation of positive ratings of the child's social activity, frequency of contacts with friends, behavior with others, and behavior by themselves. Observed outcomes were consistent with previous characterizations of children with VN as "outgoing" or "extroverted" but were not consistent with other claims that this population may be at risk for "aggressive," "attentional," or "impulsive" behavior problems.