Experimental validation of inter-subspecific genetic diversity in rice represented by the differences between the DNA sequences of ‘Nipponbare’ and ‘93-11’

The pedigrees of three sequenced rice cultivars were analyzed to show that a majority of the genetic composition of 'Nipponbare' originates from japonica cultivars while the minority originates from indica cultivars. In contrast, '93-11' is derived mainly from indica cultivars with a smaller contribution from japonica cultivars. All ancestors of 'Guang lu ai 4' appeared to be indica lines. A set of molecular markers (46 InDels and 53 SSRs) polymorphic between 'Nipponbare' and '93-11' were examined in 46 typical indica and 47 typical japonica cultivars selected from 443 accessions according to Cheng's index. All cultivars were divided into indica and japonica groups without overlapping when clustered by Cheng's index, InDels and SSRs. Much higher InDel and SSR diversity between groups than within groups implies that the marker polymorphisms between 'Nipponbare' and '93-11' represent a large proportion of inter-subspecific diversity. About 85% of indica cultivars and more than 90% of japonica cultivars were confirmed to have the same PCR banding patterns as '93-11' and 'Nipponbare', respectively. Some polymorphic loci between 'Nipponbare' and '93-11' cannot be validated in other indica and japonica cultivars, either as subspecies-specific but not predominant alleles, or alleles not specific between the two groups. It was concluded that molecular markers developed from sequence polymorphism between 'Nipponbare' and '93-11' often represent inter-subspecific diversity, although some exceptions were sensitive to either particular marker loci or particular cultivars.     

基于测试级别的软件成本模型的研究

很少有软件成本模型会考虑测试的实际情况，因此不能够准确地反映测试过程中成本的实际消耗以及当测试情况需要发生改变时对软件成本需求的变化。绝大多数的软件测试存在着不完全排错和学习过程等现象，这些现象通常反映了实际测试的成本使用情况。本文提出了一个反映实际测试情况的测试级别，在此基础上构造了一个新的软件成本模型，并讨论了基于最低软件成本的最优发布策略。实验证明该成本模型更符合软件测试的实际情况，软件开发者可以利用该模型实现对测试成本科学的管理。     

Light emission of double-walled carbon nanotube filaments doped with yttrium and europium

As the potential applications of carbon nanotubes in the field of electroluminescence,elements yttrium and europium were introduced to modify the emission properties of double-walled carbon nanotubes(DWNTs)to obtain higher efficacy and other properties.The light emission spectrum of the Y-Eu-doped DWNT filament is suppressed in the near-infrared range,while enhanced in the mid-infrared range.The doped DWNT filament can reach higher efficacy than that of the pure DWNT filament at the same input power and can...     

用动力学法研究苯乙烯─丙烯酸共聚物的序列分布

用不同的方法合成了苯乙烯（st）─丙烯酸（AA）共聚物P(St－Co－AA)．用Fineman－Ross法求出了苯乙烯和丙烯酸单体的竞聚率．按Markov一级动力学模型，求出了共聚物的序列公布．     

基于潜在低秩图判别分析的高光谱分类

提出一种基于潜在低秩图判别分析（LatLGDA）算法,利用数据的自表示对数据的列表示系数矩阵和行表示系数矩阵同时施加低秩约束,得到保留数据结构的亲和矩阵,再与图嵌入模型相结合实现高光谱图像的流形降维并进行分类。与其他基于稀疏图或稀疏低秩图的高光谱特征提取算法相比,LatLGDA可利用数据的行信息弥补列信息的不足或缺失,对噪音的抗干扰能力更强;在真实数据集上的实验结果表明,LatLGDA算法具有较高的分类精度和运算效率,应用前景广阔。     

Leptomeningeal metastasis from central nervous system tumors: A study of classification and stage in the spinal canal of 58 patients

Leptomeningeal metastasis (LM) is caused by the spread of malignant tumor cells into the subarachnoid space.However,classification and staging of LM in the spinal canal is rare in the literature.The authors reviewed the records of 58 Chinese patients with LM for clinical features,neuroimaging,and treatments.Gadolinium-enhanced magnetic resonance imaging (MRI) of brain and spinal cord were performed in all patients.Removal of intracranial tumors was performed in all patients and diagnoses were confirmed by histology.The study group consisted of 58 patients,with 29 cases presenting with intraspinal symptoms.Of the 58,8 patients underwent intraspinal tumor removal,8 received radiotherapy alone,9 received chemotherapy alone,and 34 patients received combined radiochemotherapy.We classified LM into 3 types:type L or leptomeninges LM,is subdivided into 2 subtypes (subtype LI and LII (a,b)),type N or nerve root LM is subdivided into 2 subtypes (subtype NI and NII (a,b)),and type M or mixed-type LM.We also divided LM into stages of I-IV according to the symptoms and the volume of the tumor based on spinal axial MRI.Type LI LM often occurs in patients with intracranial and intraspinal tumors found simultaneously.Patients who receive surgery for intracranial tumors may present with type N LM.Surgery is suitable for patients with NI LM and LIIb LM in stages III-IV,presenting with severe spinal symptoms.The prognosis is better for type N LM than type L LM.     

量子密码安全性研究

本文介绍了量子密码协议安全性证明的三种模型,并据此针对光源、有源光学调制器件、无源光学调制器件和探测器的非理想特性,分别度量了实际量子密钥分配系统和理想量子密钥分配协议之间的差异,并针对各种实际器件的非理想性,分析了实际量子密钥分配系统安全性存在的问题以及可能存在的攻击方案.在综合介绍国内外量子密钥分配安全性相关工作进展的同时,着重对当前的主流设备无关及半设备无关量子密码方案进行了分析阐述.     

Flaking and degradation of polyurethane coatings after 2 years of outdoor exposure in Lhasa

The exposure of a high gloss polyurethane aircraft topcoat system with polyurethane intermediate coating and epoxy primer to strong ultraviolet radiation in Lhasa, Tibet was studied by using scanning electron microscopy (SEM), atomic force microscopy (AFM), attenuated total reflectance Fourier-transform infrared (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS). Micro-flakes were found to form on the topcoat surface after exposure and the size and quantity of the flakes increased with the increase of the exposure time. The magnitude of micro-bulges and the topcoat roughness increased after a long exposure to sunlight. Flakes and micro-bulges resulted in the loss of the topcoat gloss. ATR-FTIR and XPS analysis indicated that chain scissions of the polyurea C==O group and the polyurethane C―O―C and CO―NH groups occurred, and the degradation products of NH and carbonyl groups formed due to the exposure. The breaking of the chemical structure of the polyurethane resulted in a decrease in its elasticity and in the adhesion of the flakes to its surface.     

远震P波层析成像研究羌塘中央隆起带深部结构

利用在青藏高原羌塘中部(TITAN-I项目)部署的54套流动地震台站于2008年9月至2010年11月期间所记录的506个远震事件,共9532个高质量的P波初至走时数据运用FMTT方法进行层析成像反演,获得了羌塘中央隆起带下200km的深的地壳和上地幔三维P波速度结构.结果表明:羌塘中央隆起带的南北两侧块体的岩石圈速度结构明显不同.E-W向剖面(33°和33.5°N)显示,其两侧的岩石圈结构尺度整体上存在明显差异,南北羌塘地壳整体上呈E-W向高速异常,但北羌塘的高速异常已经延伸到岩石圈地幔,且本研究区内北羌塘盆地的东部有明显的低速异常块体.而沿N-S向的两条剖面(88.5°和89.5°E)显示,羌塘中央隆起带为一明显的边界构造断裂带.     

改性废旧硅橡胶复合绝缘子胶粉与三元乙丙橡胶(EPDM)共混物的性能研究

采用硅烷偶联剂γ-甲基丙烯酰氧基丙基三甲氧基硅烷（KH570）和六亚甲基四胺/氯化铁/氯化亚铁混合物（混合改性剂）分别改性废旧硅橡胶复合绝缘子胶粉,利用衰减全反射傅立叶变换红外光谱（ATR FT-IR）和热失重分析（TGA）表征了KH570改性废胶粉的效果,并将其掺入到三元乙丙橡胶（EPDM）中制备共混物。研究了KH570和混合改性剂改性废胶粉对共混物硫化特性和力学性能的影响,通过扫描电子显微镜对共混物的断面形貌进行了分析,结果表明：经过KH570改性,成功在胶粉表面引入活性反应官能团;KH570和混合改性剂都是废旧硅橡胶复合绝缘子胶粉的有效改性剂,其中填充KH570改性胶粉的共混物在硫化性能和力学性能上均有显著提高,界面相容性也更好;随着废胶粉填充量的增大,共混物的力学性能下降。综合考虑共混物成本与性能关系,KH570改性胶粉的用量为10份时（以总橡胶质量为100份计）,共混物的综合力学性能最好。