Discovery of mitochondrial chimeric-gene associated with cytoplasmic male sterility of HL-rice

The mitochondrial genome libraries of HL-type sterile line (A) and maintainer line (B) have been constructed. Mitochondrial gene, atp6 , was used to screen libraries, due to the different Southern and Northern blot results between sterile and maintainer line. Sequencing analysis of positive clones proved that there were two copies of atp6 gene in sterile line and only one in maintainer line. One copy of atp6in sterile line was same to that in maintainer line; the other showed different flanking sequence from the 49th nucleotide downstream of the termination codon of atp6 gene. A new chimeric gene, orfH79 , was found in the region. orfH79 had homology to mitochondrial gene coxⅡ and orfH79, and was special to HL-sterile cytoplasm.     

Centennial changes of drought/flood spatial pattern in eastern China for the last 2000 years

The statistical characteristics of the bicentennial changes of the drought/flood spatial pattern over the eastern part of China have been analyzed from 101 AD to 1900 AD, and their relationship with the cold/warm climatic variation in the same time span are discussed as well. The main conclusions are as follows. (I) During the period of the 2nd ～ 11th centuries, the spatial pattern of drought/flood in the eastern part of China was characterized by thc east-west differentiation. Namely, it was dry in the west (northwest) while it was wet in the east (southeast). (ii) From the 12th to 15th centuries, the east-west differentiation coexisted with the south-north differentiation, and the former was still the dominant pattern. (iii) However, the dominant spatial pattern changed to the south- north differentiation during the 16th ～ 19th centuries, namely, it was dry in the north and wet in the south. As for the dry-wet demarcation line. It shifted westward in warn times, and once reached Datong-Taiyuan-Xi' an-Hanzhong; whereas in cold times, it retreated southeastward and reached Ji' nan-Heze-Nanyang. Furthermore, the transmeridian (W-E) dry-wet demarcation line was replaced by the meridian (N-S) dry-wet demarcation line during the two coldest periods. Moreover, in cold times, it was dry in northern China, and it was wet in the middle and lower reaches of Changjiang River and regions south of Changjiang River; in warm times, however, it was wet in northern China, and was dry in eastern China, especially in the lower reaches of Changjiang River and regions south of Changjiang River.     

The inhibiting effect of 1·4 recombinant P chromosome of wheat-<Emphasis Type="Italic">Agropyron cristatum</Emphasis> addition line on the <Emphasis Type="Italic">Ph</Emphasis> gene

P chromosomes may carry a genetic system that inhibits the Ph gene in wheat. Abnormal chromosome synapsis in wheat-Agropyron cristatum addition line II-21-2 (additional 1·4 recombinant P chromosome) was observed in this study. The results of cytogenetics and Ph1 gene amplification showed that the Ph1 gene was normal and the average number of quadrivalents or hexavalents was determined to be 0.41 and 0.13, respectively, in pollen-mother cells of wheat-Agropyron cristatum addition line II-21-2. The analysis o...     

Homoharringtonine induces apoptosis of endothelium and down－regulates VEGF expression of K562 cells

Homoharringtonine (HHT) has currently been used successfully in the treatment of acute and chronic myeloid leukemias and has been shown to induce apoptosis of different types of leukemic cells in vitro. Emerging evidence suggests that angiogenesis may play an important role in hematological malignancies, such as leukemia. However, whether HHT can relieve leukemia by anti-angiogenesis is still unknown. We investigated the anti-angiogenesis potential of HHT with the human umbilical vein endothelial cell line (ECV304) and leukemic cell line (K562) in vitro. Cellular proliferation was determined by MTT assay and apoptosis was analyzed by flow cytometry, The mRNA expression of vascular endothelial growth factor (VEGF) was assessed by RT-PCR and VEGF protein production was detected by Western blot. Inhibition of cell proliferation and induction of apoptosis by HHT were discovered in ECV304 cells, and appeared in a dose- and time-dependent manner, Also, treatment with HHT caused down-regulation of VEGF mRNA expression in K562 cells in similar dose- and time-dependent manner and inhibition of VEGF protein production in K562 cells in response to the enhancing concentration of HHT. The results demonstrated that HHT could also induce apoptosis in endothelium and down-regulate VEGF expression in K562 cells. In conclusion, we believe HHT has anti-angiogenesis potential and speculate that HHT might exert its anti-leukemia effects via reduction of angiogenesis.     

A brief introduction to National Laboratory for Superconductivity, Institute of Physics, Chinese Academy of Sciences

In line with the rapid development of research on high-temperature superconductors, the establishment of a National Laboratory for Superconductivity in the Institute of Physics, the Chinese Academy of Sciences (CAS) was ratified by the State Commission of Development & Planning (SCDP) in 1987. The preparations were started in 1988, and in April of 1991,the Laboratory was finally established, accepted and listed as a National Laboratory open to both domestic and foreign researchers. After the joint appraisal and acceptance by the National Natural Science Foundation of China and the Ministry of Science & Technology, it was honored with a title of the Outstanding National Laboratory in 2000.     

Analysis of CVC roll contour and determination of roll crown

Mathematical analysis of continuous variable crown (CVC) roll contour used in CSP production line was conducted and the roll contour function of CVC roll was obtained. The validation with actual CVC roll contour shows that the calculation values of the roll contour function and the actual roll contour parameters given by equipment provider are the same, which proves that the roll contour function of CVC rolls given in this article is correct. The nonlinear relationship between the roll crown of CVC rolls and roll shift amounts was deduced. The concept of crown extremum was given.     

Linear and nonlinear optical changes in amorphous As2Se3 thin film upon UV exposure

Amorphous As_2Se_3 chalcogenide thin film was exposed to UV light(i line and g line) using mercury lamp for 30 min. XRD,UV/VIS spectroscopy and thickness measurements were taken for unexposed and exposed thin film for structural and optical characterizations.Linear optical constants(linear refractive index,extinction coefficient and linear optical absorption coefficient) of the film were calculated from transmission spectra using Swanepoel method.Optical bandgap was determined using Tauc's relation of in...     

New Voronoi Diagram Algorithm of Multiply-Connected Planar Areas in the Selective Laser Melting

This paper studies the practical generation of Voronoi diagrams for multiply-connected planar areas bounded by line segments. The core of the algorithm was calculating Voronoi polygon of every Voronoi object in planar areas independently. The main approach had two steps. The first step was calculating all relevant bisectors of every Voronoi object. The second was combining obtained bisectors into completed Voronoi polygons individually. All code was implemented in Visual C++ platform. The resulting code was extensively tested in real-world data and its practical running time grew only linearly. Three statistical CPU-consumption charts had been drawn with the Voronoi diagrams computation data, and compared with other published codes for computing Voronoi diagrams. The algorithm was applied to compute offsetting of slice area consisting of large-scale line segments for the selective laser melting (SLM) trajectory scanning technology which is a kind of rapid prototyping (RP). The experimental results of offsetting for slice area based on Voronoi diagrams show that the approach is effective and simple for polygon offsetting problems. The method is helpful to those offsetting work and can provide more effective offsetting solution.     

Isolation of a pollen specific promoter in tritordeum

The promoter is a cis-acting element in regulating gene expression. A promoterless plasmid containing UidA gene was transformed into tritordeum by barmbadment. Histochemical analysis of various tissues in transgenic tritordeum was carried to examine tissue-specific expression of GUS(beta-glucuronidase) activity. The pollen-specific promoter was trapped and identified successfully in a transformant line. PCR(polymerase chain reaction) method was used to isolate this pollen-specific promoter. By sequencing and analyzing the amplified fragment from PCR, a part of UidA gene and a flanking sequence were obtained. Some essential elements of plant promoters were found in the sequence. To determine the function of it, the cloned fragment was fused with UidA gene, then cloned and transformed into Triticum durum. The transgenic plant transformed by this vector showed GUS expression only in pollen. Therefore a pollen-specific promoter was isolated successfully.     

Neural correlates of short-term perceptual learning in orientation discrimination indexed by event-related potentials

The current work investigated the neural correlates of visual perceptual learning in grating orientation discrimination by recording event-related potentials (ERPs) from human adults. Subjects were trained with a discrimination task of grating orientation in three consecutive training sessions within 2 h. While reaction times (RTs) were shortened gradually across training sessions, the N1 was decreased and the P2 was increased over the parietal and occipital areas. A broadly distributed P3 was increased along with more practices. In addition, the time course of learning reflected in the P2 and P3 amplitudes was in line with the changes of reaction times and exhibited a stable level during later training. The impli- cations of these results to the neural mechanisms subserving perceptual learning were discussed.     

水稻光温敏核不育系培矮64S在东南亚的育性气候适应性分析

以曼谷、清迈（泰国）、密支那（缅甸）1980～1997年逐日4时次气温观测资料为基础，并用NCEP／NCAR再分析资料通过回归分析补全缺测值，通过Cressman插值法得到河内（越南）的同期逐日气温序列，结合四地理论日长计算结果和用国内分期播种资料计算的培矮64S的育性转换指标集及发育期模型，对其在东南亚3国的育性气候适应性进行了分析，并给出了90％、95％、100％保证率下安全制种和繁殖的最早、最晚播种期，计算了相应的风险概率。     

水稻光温敏雄性不育基因连锁标记的分离与鉴定

两系法杂交稻是一种利用水稻杂种优势的重要途径，主要依据水稻光温敏雄性不育系在不同条件下的育性转换用于配制杂交种．以培矮64S(PTGMS)与明恢63杂种自交的F2代为供试材料，采用随机放大多态性DNA(RAPD)技术分离与培矮64S的PTGMS基因连锁的分子标记．在F2代2个分别代表可育和不育的群体以及亲本株系中，采用100个RAPD引物扩放基因组DNA筛选多态性DNA片段．RAPD引物S8产生的DNA片段中，除重复顺序外，有一个长度为0．85kb片段为单拷贝．分子杂交表明，这一单拷贝标记与培矮64S的PTGMS基因连锁．     

病毒性心肌疾病的基因时空表达特征

目的 研究病毒性心肌炎到扩张型心肌病全病程基因时空表达谱动力学特征.方法 用含有8 000个基因克隆的基因芯片检测CVB3反复感染Balb/c小鼠后第0,7,21天及第3,6,9个月心肌组织基因表达,并用SOM对差异性表达的基因进行聚类分析.结果（1）第10,14,15,19,20类基因在第7天时表达上调,第21,22类基因在第21天表达上调,而第23,24类基因在第7、21天表达均上调;（2）第6,7,11,12类基因在第7天时表达下调,第4,5类基因在第21天表达下调,而第2,3,8类基因则在第7,21天表达均下调;（3）第1,16类基因在第7天时表达下调,而第21天后则表现为上调;（4）有些基因如转移生长因子β结合蛋白、β-2微球蛋白,CD 53抗原却表现为持续性表达上调,而α-1微球蛋,ninjurin 1,舒血管素27,cytokine inducible SH2-containing protein 2则出现持续性表达下调.结论 建立了小鼠CVB病毒性心肌炎及扩张型心肌病全病程基因表达谱动力学模式,为进一步了解其分子发病机制提供全新的视野.     

抗广谱除草剂pursuit水稻的抗性遗传分析和利用

以4个恢复系测64、明恢63、特青和02428为母本,分别与抗除草剂pursuit(普杀特)水稻品种PT2杂交,遗传分析表明,PT2的抗性遗传符合一对显性核基因的模式.通过杂交一代和回交二代已将抗性基因转移到恢复系,初步培育出4个抗性恢复系测64-P、明恢63-P、特青-P和02428-P;它们与不育系杂交,选育到4个杂交稻组合.考种结果发现,抗除草剂组合基本上能保持原组合的产量水平,苗期喷药可完全淘汰假杂种.利用这项技术可望解决三系、两系或化学杀雄杂交稻制种过程中出现的纯度问题,且有利于新杂交稻组合的选育.对该项技术在生产上的应用前景和存在问题进行探讨.     

Isolation of cDNA fragment of fertility-related gene in photoperiod-sensitive genic male sterile rice

The photoperiod_sensitive genic male sterile rice (PGMR) is particularly useful to take advantage of heterosis in rice. mRNA differential display was used to isolate the fertility_relative genes in rice. After establishing an optimized mRNA differential display system, one of the differential cDNA fragments that maybe related to the development and maturation of rice panicle was cloned from a PGMR Nongken 58S.     

水稻新资源温敏核不育系长S育性基因的等位性测验

长S来自普通野生稻与籼稻珍珠矮杂交后代。在自然条件下,长S表现为长日高温可育、低温不育,且育性转换明显。经等位性测验,长S与C815S、广占63S、株1S、湘陵628S及HD9802S的育性基因等位,而与HN5S、培矮64S的育性基因不等位。     

水稻籼粳杂种多倍体亲本开花习性的研究

对强优势水稻四倍体杂交组合的亲本HN2026、SG99012、培矮64S及二倍体不育系培矮64S的开花习性进行观察研究．结果表明：具有高结实率特性的四倍体品系HN2026、SG99012如同二倍体的培矮64S一样,开花习性较为正常,即开花期和开花时间集中,表现出明显的高峰期;而四倍体的培矮64S则表现异常,主要表现为：颖花开张持续时间长、日开花时间分散、缺少明显的日开花高峰期,而且随着气温的升高,有颖花开张持续时间缩短、日开花高峰期后移的趋势,并对这种异常情况的可能原因进行了粗略的分析．     

水稻光温敏核不育系4112S和YW-2S的开花习性观察

通过对水稻光温敏核不育系4112S和YW-2S的开花习性的观察,发现这两个不育系具有开花集中,颖花开颖时间长,张颖角度大,柱头外露率高,柱头生命力不太长且下降快等特点．并就其高产稳产的制种技术措施进行了讨论．     

利用广亲和品种提高“三系”杂交稻优势的探讨

对02428、cpslo17、培矮64在三系杂交稻中的利用进行分析,结果表明,亲和力高低依次为cpslo17、培矮64、02428。cpslo17、培矮64含有对籼粳不育系的恢复基因,02428含有对粳稻不育系的恢复基因。三者与BT型不育系的产量配合力都较好,杂种有明显的优势。单株产量主要受单株有效穗数和每穗粒数的影响。