海湾扇贝微卫星标记的开发及遗传连锁图谱的构建

海湾扇贝（Argopecten irradians）不连续分布于美国大西洋沿岸和墨西哥湾沿岸，自1982年以来北部亚种（A. i. irradians）和南部亚种（A. i. concentricus）被先后引进到中国，由于其生长速度快、繁殖周期短和适宜温度范围广的特点，迅速成为我国海水养殖的重要品种。近年来飞速发展的分子标记技术为优良品种的选育注入了新的活力，相对于传统的表型选择来说，标记辅助选择不易受环境的影响，尤其是对于低遗传力性状和后期表达的性状，能增强选择效率，提高选择的准确度，缩短育种周期。本文通过构建海湾扇贝微卫星富集文库获得大量的微卫星DNA序列，筛选多态的微卫星标记构建了海湾扇贝的遗传连锁图谱，并应用复合区间作图法对生长相关性状进行了QTL定位。 本研究利用富集文库-菌落原位杂交法筛选海湾扇贝微卫星DNA，吸附(AC)15和(AG)15探针的尼龙膜捕捉并富集含有微卫星序列的片段，菌落原位杂交结果显示阳性克隆率达到40%，测序比对后获得521个独立的阳性克隆，其中微卫星506个，小卫星15个。微卫星中，完美型248个，占49.0%，非完美型216个，占42.7%；复合型42个，占8.3%；AG/TC重复占大多数（356个，70.4%），AC/TG重复有150个（29.6%）。设计合成了382对引物，利用38个海湾扇贝个体对其中15个微卫星位点进行了遗传多样性评价，不同位点扩增得到的等位基因数从3到7个不等，期望杂合度和观测杂合度的范围分别为0.198~0.813和0.083~0.833，实验结果表明富集文库-菌落原位杂交法适合大规模筛选微卫星标记。 利用8个微卫星标记对海湾扇贝1个野生种群和3个养殖群体的遗传多样性与分化进行了比较和分析。8个位点共扩增得到35个等位基因，平均每个位点4.38个等位基因，平均有效等位基因数为2.30，平均观测杂合度和期望杂合度分别为0.41和0.46。相比于野生群体（美国），养殖群体（北卡罗来那、浙江和胶南）的等位基因数和杂合度都有所降低，在封闭环境下养殖19代的浙江群体等位基因数丢失最严重，共有9个等位基因丢失（25.7%）。经过多代人工养殖后，海湾扇贝养殖与野生群体之间和养殖群体之间出现了明显的遗传分化，胶南群体与野生群体的遗传距离最大，而胶南群体与浙江群体的遗传距离已经超过了胶南群体（北部亚种）和北卡罗来那（南部亚种）群体的遗传距离，这种分化将有利于海湾扇贝的杂交选育。 利用167个微卫星标记和1个壳色标记，以海湾扇贝2个全同胞F1代为作图群体，构建了海湾扇贝的性别遗传连锁图谱。整合的雌性连锁图谱含有118个标记，覆盖了16个连锁群，每个连锁群含有的标记数目从4到16个不等，平均每个连锁群上有7.4个标记，图谱总长度为761.0 cM，标记间的平均间隔为8.55 cM，图谱的覆盖率为73.5%；整合雄性连锁图谱含有126个标记，覆盖了17个连锁群，每个连锁群含有的标记数目从2到11个不等，平均每个连锁群上有7.4个标记，图谱总长度为729.1 cM，标记间的平均间隔为6.75 cM，图谱的覆盖率为74.7%。雌性亲本的重组率高于雄性，雌雄亲本共享标记间的重组率比值为1.18：1。偏分离标记在性别间呈现不对称分布，雄性亲本的偏分离高于雌性亲本，可能与雄性亲本来源于亚种间杂交的遗传背景相关。 利用海湾扇贝微卫星遗传连锁图谱在两个作图家系中对5个生长性状的QTL进行了定位，5个生长性状的表型相关均达到极显著水平（P < 0.01），Pearson相关系数均超过0.781，总重、壳长、壳宽、壳高和壳重的QTL（LOD > 2.0）的数目分别为8、6、6、7和6个。这些QTL成簇分布于CC5家系的LG1、LG3、LG4、LG8和CC10家系的LG1、LG3、LG6、LG8、LG9连锁群，单个QTL可解释的表型方差为5.5%到29.2%，QTL成簇分布现象说明这些生长相关的性状可能具有共同的遗传基础，家系特异性QTL暗示在不同的遗传背景和环境下存在不同的主效QTL。本研究定位的QTL，尤其在两个家系中共享的QTL为下一步分子标记辅助选择提供了参考区间。

Seasonal variations in growth and clearance rate of the Zhikong scallop Chlamys farreri suspended in the deep water of Haizhou Bay, China

The growth and survival of the Zhikong scallop Chlamys farreri suspended in deep water of Haizhou Bay were studied from July 2007 to June 2008, and the biodeposition method was used to estimate the clearance rate of C. farreri under field conditions. Results showed that the scallop grew fast during all the culture time, with the exception of summer. The condition index of the scallop increased with time and reached the highest value in spring of the second year. The survival of scallops was 60.8 +/- A 3.9% at the end of this study, mortality occurring mainly during the summer and autumn of the first year. The clearance rate fluctuated obviously with season,with the highest value in September 2007, and the lowest value in March 2008. Factors accounting for variations in growth and clearance rate of scallops are also discussed.

A set of polymorphic microsatellite loci for the bay scallop, Argopecten irradians

The method of creating enriched microsatellite libraries can supply an abundant source of microsatellite sequences at a considerably reduced cost. Here we report the development of 15 polymorphic microsatellite loci from the bay scallop, Argopecten irradians, using enrichment protocol. Polymorphism was assessed in a sample of hatchery population (n = 38) revealing three to seven alleles per locus. The expected and observed heterozygosities ranged from 0.198 to 0.813 and from 0.083 to 0.833, respectively. These markers will be useful for genetic variation monitoring and parentage analysis.

A NOVEL BROMOPHENOL FROM MARINE RED ALGA Symphyocladia latiuscula

2,3,6-Tribromo-4,5-dihydroxybenzyl ethyl ether (1), a new bromophenol, was isolated from the ethanol extract of marine red alga Symphyocladia latiuscula, with a known compound, 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether ( 2). Their structures were elucidated by spectroscopic analysis, including high-resolution mass spectroscopy, and 1 and 2-dimensional NMR techniques. Compounds 1 and 2 showed inhibitory activity against Staphyloccocus aureus with IC50 102 and 50 mu g/mL, respectively.

藏药五脉绿绒蒿的化学成分研究

从传统藏药五脉绿绒蒿(Meconopsis quintuplinervia Regel.)全草乙醇提取物中分离得到 6个化合物,利用波谱方法鉴定为 8,9-dihydroxy-1,5,6,10b-tetrahydro-2H-pyrrolo[2,1-a]isoquinolin-3-one(1)、甲氧基淡黄巴豆亭碱(o-methylflavi nantine,2)、黑水罂粟碱(murine,3)、tricin(4)、木犀草素(luteolin,5)以及β-谷甾醇(β-sitosterol,6).其中化合物1,4为首次从该植物中分得.

生物资源面临的严重威胁：生物多样性丧失

全球据科学家估计有1400×10^4种生物，但其丧失速度非常惊人。文中指出目前大约有492种乔木的遗传多样性受到威胁；未来将有5％－20％的动植物种群濒临灭绝，6×10^4种植物在今后20a里可能灭绝。生物多样性丧失原因为：生物资源需求量的剧增，但管理不力，缺乏利益权衡，不合理的生产活动，自然栖息地被人为占用，土壤、空气、水的污染等等。

Rhein induces apoptosis and cell cycle arrest in human hepatocellular carcinoma BEL-7402 cells

Rhein, an anthraquinone derivative of rhubarb, inhibits the proliferation of various human cancer cells. In this paper, we focused on studying the effects of rhein on human hepatocelluar carcinoma BEL-7402 cells and further understanding the underlying molecular mechanism in an effort to make the potential development of rhein in the treatment of cancers. Using MTT assay and flow cytometry, we demonstrate a critical role of rhein in the suppression of BEL-7402 cell proliferation in a concentration- and time-dependent manner. The increase of apoptosis rate was observed after incubation of BEL-7402 cells with rhein at 50-200 mu M for 48 hours, and the cells exhibit typical apoptotic features including cellular morphological change and chromatin condensation. Moreover, rhein-induced cell cycle S-phase arrest. Additionally, after rhein treatment, expression levels of c-Myc gene were decreased, while those of caspase-3 gene were increased in a dose-dependent manner by using real-time PCR assay. The results demonstrate for the first time that cell cycle S-phase arrest is one of the mechanisms of rhein in inhibition of BEL-7402 cells. Rhein plays its role by inducing cell cycle arrest via downregulation of oncogene c-Myc and apoptosis through the caspase-dependent pathway. It is expected that rhein will be effective and useful as a new agent in hepatocelluar carcinoma treatment in the future.

峨眉山玄武岩分布区内铂族元素异常分析及其找矿远景预测

区域地球化学填图成果表明，在中国西南川-滇-黔交界地区存在一个与产出规模巨大的峨眉山玄武岩分布范围相吻合的Pt，Pd地球化学巨省。作为地幔热柱成因的峨眉山玄武岩的铂族元素丰度虽略有偏高，但玄武岩中铂族元素很难形成可以利用的铂族矿物，故该异常是“非找矿异常”。在该区内寻找铂族元素矿床应在基性岩-超基性岩体出露较多的中岩区南段，注意沿循已知的矿床、矿化或较小型基性岩侵入体，将矿区(或岩体)的整体地质特征、地球化学特征等与典型的岩浆型铂族元素矿床相比较，进而研究、预测本矿区或本岩体的铂族元素成矿的可能性及远景规模等，寻找岩浆型铂族元素矿床，而在岩浆型矿床的周边地质体内注意寻找热液型铂族元素矿床。

Formation of the V center on H-type zeolites with thermal treatment

The effect of thermal treatment on H-MCM-22 and H-ZSM-5 zeolites was investigated using the electron spin resonance technique. A six-line signal (denoted as A, g = 2.048, A = 22. 15 G) was detected on H-MCM-22 after He purging at high temperatures, whose intensities increased with the treating temperature. The same signal was also found on H-ZSM-5 zeolites with different crystal sizes. The paramagnetic center was identified as a V center, namely, a hole of an electron trapped on an oxygen atom bonding to a nearby aluminum atom. These signals appeared only on a dealuminated sample or a sample concomitantly with dealumination. The formation of the hole might involve an electron transferring from the lattice oxygen to a nonframework aluminum species, and the hyperfine splitting is caused by the interaction between the electron hole locating on the p orbit of oxygen and the framework aluminum bonding with the oxygen. The signal disappeared after the sample was exposed to air or oxygen at room temperature. However, the process was reversible. A new set of signals (denoted as B, g(1) = 2.008, g(2) = 2.003, g(3) = 1.9985) was observed after oxygen adsorption on the H-MCM-22 pretreated with He at 973 K or He purging at 973 K on the H-MCM-22 pretreated with oxygen at 813 K, which was attributed to the O- species.

Relationship between the molybdenum phases and the conversion of n-butane over Mo/HZSM-5

The conversion of n-C4H10 was undertaken on MoO3/HZSM-5 catalyst at 773-973K and the phases of molybdenum species were detected by XRD. The XRD results show that bulk MoO3 on HZSM-5 can be readily reduced by n-C4H10 to MoO2 at 773 K and MoO2 can be gradually carburized to molybdenum carbide above 813 K. The molybdenum carbide formed from the carburization of MoO2 with n-C4H10 below 893 K is alpha-MoC1-x with fcc-structure, while hcp-molybdenum carbide formed above 933 K. During the evolution of MoO3 to MoO2 (>773 K) or the carburization of MoO2 to molybdenum carbide (>813 K), deep oxidation, cracking and coke deposition are serious, in particular at higher reaction temperatures, these lead to the poor selectivity to aromatics. Aromatization of n-C4H10 can proceed catalytically on both Mo2C/HZSM-5 and MoO2/HZSM-5, the distribution of the products for the two catalysts is similar below 813 K, but the, activity for Mo2C/HZSM-5 is much higher than that for MoO2/HZSM-5. (C) 2002 Elsevier Science B.V. All rights reserved.

Studies of the solar mean magnetic field with the Birmingham Solar-Oscillations Network (BiSON)

Chaplin, W. J.; Dumbill, A. M.; Elsworth, Y.; Isaak, G. R.; McLeod, C. P.; Miller, B. A.; New, R.; Pint?r, B., Studies of the solar mean magnetic field with the Birmingham Solar-Oscillations Network (BiSON), Monthly Notice of the Royal Astronomical Society, Volume 343, Issue 3, pp. 813-818. RAE2008

Constructing Enemies: 'Islamic Terrorism' in Political and Academic Discourse

Jackson, Richard, (2007) 'Constructing Enemies: 'Islamic Terrorism' in Political and Academic Discourse', Government and Opposition, 42(3) pp.394-426 RAE2008

La elipse como lugar geométrico a través de la geometría del doblado de papel en el contexto de Van Hiele

El presente artículo es un producto derivado de la investigación: “La elipse como lugar geométrico a través de la geometría del doblado de papel en el contexto de Van Hiele”, en la que se analizó el proceso de comprensión del concepto de elipse como lugar geométrico, de cinco estudiantes del grado décimo de una Institución Educativa de la ciudad de Medellín. El estudio de casos cualitativo permitió el establecimiento de los descriptores de los niveles de razonamiento de Van Hiele que caracterizaron dicho proceso de comprensión y a su vez, iluminaron la creación de un guion de entrevista de carácter socrático, que se convirtió en una experiencia de aprendizaje para los estudiantes en tanto que les permitió avanzar en su nivel de razonamiento.

Ecuación vectorial de una recta: una propuesta didáctica desde la teoría antropológica de lo didáctico

La presente investigación surge en el programa “perfeccionamiento en matemática para profesores de enseñanza media” realizado en el IUFM le Mirail, Universidad de Toulouse, Francia. El estudio consiste en el diseño de una propuesta didáctica para el aprendizaje de la ecuación vectorial de una recta en el espacio, en estudiantes de 16 a 18 años, el interés nace por la incorporación de estos temas en el curriculum nacional. Para el diseño de la propuesta se utiliza elementos de la Teoría Antropológica de lo Didáctico (TAD), donde se entenderá como organización matemática, a un conjunto de tipos de tareas, de técnicas o procedimientos para resolver estas tareas y de definiciones, propiedades y teoremas que permitan describir y justificar la resolución de la tarea. Entre los elementos que aportan en el surgimiento de la organización matemática, se distinguen, tipos de tareas como, establecer si puntos del plano o el espacio son colineales y determinar las condiciones para que un tercer punto sea colineal a dos puntos dados, en el plano o en el espacio.