水稻小G蛋白Arf GTPase激活蛋白OsAGAP功能研究

　　锌指蛋白在植物生长发育中具有重要功能，它们可以识别并结合特定的DNA序列进行转录调控，还能够参与蛋白之间相互作用的调节。我们根据锌指蛋白等转录因子特征结构域的序列特点，从来自10 K水稻芯片的EST数据库中筛选出编码58个EST序列。通过对器官表达特异性的比较分析，从中选出七个只在单一器官表达的基因，并对这七个基因的功能进行研究。对其转基因水稻的表型分析发现，C1基因调节水稻的株高和穗的发育;LIM 家族的F9影响小花的形态，主要体现在雌蕊与雄蕊的发育;锌指蛋白S34调控叶倾角的变化;F14基因编码一个核定位的TFIIIA类锌指蛋白，具体功能尚不清楚;锌指蛋白F35转基因水稻主根缩短，侧根数目显著减少。它编码一个推测的ArfGAP (Arf GTPase activating protein)，据此我们将其命名为OsAGAP，并对其进行深入研究。 　　OsAGAP的cDNA全长为1328bp，编码的蛋白由320个氨基酸组成，含有两个保守结构域：锌指结构域和C2 结构域。其中锌指结构域属于CX2CX16CX2C类，即ArfGAP domain的特征结构。GTP酶活性测定试验表明，OsAGAP蛋白能够激活水稻Arf的GTP酶活性，另外，OsAGAP还能够恢复酵母ArfGAP缺失突变体的表型。说明OsAGAP编码的蛋白是水稻中的一个ArfGAP。 　　OsAGAP在水稻各器官中均有表达，但强弱有所不同。RNA原位杂交结果显示，它在茎尖分生组织与侧生原基及侧根部位表达强烈;它在根尖主要分布于中央维管组织、分生区、皮层细胞，最有趣的是恰好与生长素在根尖极性运输路径相吻合。在亚细胞水平，OsAGAP广泛分布于细胞膜、细胞质、细胞核。 　　OsAGAP超表达水稻主根、不定根长度缩短，侧根数目显著减少表现出类似于生长素极性运输突变体的表型。其主根伸长对TIBA的抑制作用不敏感，这暗示OsAGAP超表达水稻的生长素极性运输被破坏;另外，其对各种生长素的作用敏感性也发生变化，对IAA、2,4-D的不敏感，而对NAA的反应与野生型一致，根据各类生长素进出细胞机制不同，可以推测超表达水稻的输入能力存在缺陷。极性运输实验结果表明，超表达水稻极性运输能力被破坏;对生长素输入能力的测定进一步表明，超表达水稻根载体的介导的生长素输入能力显著下降。另外，NAA处理能够恢复超表达水稻中侧根发育受抑的表型缺陷。由此可见，OsAGAP在水稻中超表达破坏了生长素极性运输的输入能力。 　　FM1-43是一类特异标记囊泡运输的荧光染料。经其染色标记后，OsAGAP超表达水稻细胞内囊泡成片聚集，形成“BFA区间”，表现出囊泡运输被破坏的典型特征。透射电镜观察发现，超表达水稻细胞内有大量的小液泡，其中积累了电子密度很高的颗粒物质。由此推测，可能由于细胞的囊泡运输被破坏，导致胞内的代谢物质不能被正常运送或分泌，而在液泡中暂时贮存以维持细胞环境的稳定。 　　在酵母和动物细胞中的研究表明， ArfGAP是调控囊泡运输的一个重要因子，然而目前还没有关于ArfGAP在植物细胞中生理作用的报道。我们的结果说明，OsAGAP作为的一个ArfGAP，它通过调控水稻中的囊泡运输，而影响了生长素的极性运输，具体表现在对生长素输入能力的调控。由此，我们推测ArfGAP可能在生长素的极性运输中也起着重要的调控作用。 　　但OsAGAP在拟南芥中却通过调控植株生长素的水平，而影响了转基因拟南芥根的发育。每种生物都有多个ArfGAP，它们之间的分工存在联系，但各不相同。OsAGAP是拟南芥的外源基因，它在拟南芥中可能以不同于水稻的机制起作用。

功能菌剂的混合发酵研究

随着化工行业的发展，大量有毒有害难降解有机物随工业废水的排放进入环境，这些物质能够在环境中长期存在、积累和扩散，通过食物链对动植物的生存及人类的健康造成不良影响。本文以苯酚、对氯硝基苯、氯苯和十六烷为模拟污染物，以前期研制的功能菌剂为对象，经过紫外线线诱变筛选出优于出发菌株的功能菌，对诱变后功能菌的理化性能进行了研究，对菌种进行了鉴定，在此基础上，就其相互之间的微生态关系进行研究，为混合发酵提供理论基础，并就其最佳发酵条件及发酵参数进行了研究，最后对发酵产品的性能进行了检测。目前，国内外有关功能菌剂的研究还存在多方面的不足，主要包括：①由于多菌种混合发酵过程较为复杂，各菌之间存在复杂的相互作用，影响因素较多，关于菌种之间的相互关系研究得很少，环境功能菌剂的发酵方法大多采用单独发酵后混合的方式。单独发酵对原材料、设备和能源的利用率较低，对于多菌种制剂发酵，在设备、能源和原材料的方面造成的浪费更大，将会大幅增加菌剂的生产成本，影响多菌种功能菌剂的发展；②功能菌剂生产过程的质量控制方面研究得较少；③功能菌剂产品的稳定性、抗冲击性能研究得较少，对环境微生物制剂的研究主要集中在菌种选育和培养条件优化方面。 通过本论文研究，得到以下主要结论。 （1）在紫外线诱变处理中，用紫外线对发生一定程度退化的出发菌株进行诱变处理后，六株具有高效降解性能的菌株被筛选出来，诱变筛选出的菌株形态和ERIC-PCR指纹图谱与出发菌株相比发生了明显改变；而且诱变后的菌株对目标难降解底物的降解能力均得到改善，其中，FPN、FCB、F14、FEm对目标底物的降解率提高了20%以上；诱变后菌株经过7次连续传代接种后，对目标难降解底物的降解率无显著变化，具有一定的遗传稳定性。并对诱变后的功能菌进行了初步的鉴定，这6株菌都分别是芽孢杆菌。 （2）对诱变后的功能菌相互之间的微生态关系进行了研究，通过抑菌实验、生长量以及基质消耗量的比较，确定它们之间的生长关系是无害共栖关系，可以进行混合发酵。 （3）对该功能菌剂进行发酵培养条件研究，结果表明发酵培养基的最佳成分（g/L）：葡萄糖 31.0g/L、玉米粉10.0g/L、磷酸氢二钾1.0g/L、硫酸铵1.1g/L、硫酸镁0.55g/L。通过研究不同的培养条件对菌体生长和降解性能的影响，确定了最佳培养条件：培养基初始pH7.5；最适温度32℃；培养基装液量125mL（250 mL三角瓶），以及培养时间对降解性能的影响，培养20 h的产物对降解最为有利。通过研究添加不同目标污染物对菌体生长和降解性能的影响，确定了添加目标污染物的最佳量以及最佳时间：苯酚投加量：1.125 g/L，对氯硝基苯投加量：0.1 g/L；最佳投加时间为发酵培养开始后4 h。 （4）以摇瓶分批发酵最优条件为基础，对FPN、F10、FCB、FNa、F14 和 FEm进行了摇瓶分批发酵试验。以摇瓶分批发酵试验数据为依据，对功能菌剂分批发酵动力学进行了研究，建立了菌体生长和基质消耗的动力学模型，拟合模型能较好的反映功能菌剂分批发酵过程。 （5）功能菌剂和活性污泥协同作用，可以提高系统的生物降解能力，功能菌剂投加量为2%，新鲜活性污泥3500 mg/L，降解24 h条件下，功能菌剂和活性污泥的协同作用对COD的去除率和对照组相比，最多的提高了36.8%。功能菌剂和活性污泥协同作用以及活性污泥的单独作用，其生物降解过程均符合一级反应动力学过程，功能菌剂和活性污泥协同作用的生物降解动力学方程为：，相关系数97%。采用SBR运行方式，引入功能菌剂的SBR系统明显能够改善和提高生物降解的效率。与仅有活性污泥的系统相比，系统对COD的平均去除率可以提高27.1%，同时，系统的耐负荷冲击以及耐毒害冲击的性能比仅有活性污泥的SBR系统强，特别是负荷冲击对引入功能菌剂的SBR系统影响很小。仅有活性污泥的SBR系统经过负荷冲击和毒害冲击之后，不能恢复到冲击之前的水平，而且系统有效作用时间的周期比引入功能菌剂的SBR系统相比大大缩短，而引入功能菌剂的SBR系统处理效果较为稳定，恢复能力很强。 Along with the development of industries, many recalcitrant organic chemicals have been discharged into natural environments together with wastewaters and can exist in waters, soil and sediments for a long time without degradation. These haz-ardous substances, their byporducts and metabolizabilities can be highly toxic, mu-tagenic and carcinogenic, thereby threatening animals, plants and human health through food chain. Consequently the removal of these compounds is of significant interest in the area of wastewater treatment. In this dissertation, the phenol, hydro-quinone, chlorobenzene and hexadecane treated as the model pollutants, the func-tional microorganism agent was used as the starting strains, they treated with ultra-violet light, and then the mutant strains with high degradation ability were screened out and identified primarily, the relationship between these stains were studied, the medium composition and fermentation conditions were optimized, the degradation ability of the fermented production was tested. The literature survey indicates that the study of the microorganism agent is far from complete and more information is re-quired on following problems. 1, Because of the complexity of relationship in mixed fermentation and the complicated factors, the study is hardly to process.2, There is a lack of information on the quality control of the producing process .3, And there is a lack of information on the stability about the microorganism agent. In this dissertation, the main results of the present study could be summarized as follows: (1)The degenerate starting strains were treated with the ultraviolet light, and six mutant strains with high biodegradation ability were screened out by using the me-dium with selective pressure of model pollutants. The mutant strains had great changes in colonialmorphology and ERIC-PCR fingerprinting. And the mutant strains got obvious advantages over the starting strains in degradation ability and over 20% improvement of removal rates was achieved for FPN、FCB、F14 and FEm. The de-gradation ability of the mutant strains was stable after seven generations. After that, the mutant strains were primarily identified as bacillus respectively. (2) The relationship between these mutant strains was studied. By the compari-son of antibiosis effect, biomass and consumption of substrate, the relationships were neutralism and they could be mixed fermented. (3) The optimized cultivation conditions were as follows: glucose 31.0 g/L, corn power 10 g/L, K2HPO4 1.0 g/L, (NH4)2SO4 1.1 g/L, MgSO4 0.55 g/L, initial pH7.5, temperature 32℃, working volume 125 mL/250 mL, and cultivation time 20h (con-sidering the time effect on degradation ability), adding pollutants phenol (1.125 g/L) and hydroquinone (0.1 g/L) into the broth at 4 h after cultivation. (4) Based on the above optimum condition, the batch fermentation was per-formed with strains FPN, F10, FCB, FNa, F14 and FEm in shake flask. The batch fermentation kinetics was studied based on the experimental data. Two kinetic models were constructed which could reflect the regularity of growth and substrate consump-tion in the process of batch fermentation. (5) The co-operation of functional microorganism agent and activated sludge could raise biodegradation of system by adding some microorganism agent and 3500 mg/L fresh activated sludge. Bioaugumentation by the addition of high effective deg-radation culture enhanced the treatment effect of SBR system and the COD removal rate was increased by 20%-36.8%. Its biodegradation matched first-order dynamical reaction equation, and the reaction equation was ln0.2327.391ct=−+. The micro-organism agent had the effect of optimization to activated sludge micro-ecosystem. The SBR system adding 2% microorganism agent, the average COD removal rate of that was increased by 27.1% and stronger anti-shock ability to load and toxicant were achieved (compared with SBR system just adding activated sludge). Especially the load-shock has barely effect to the SBR system adding microorganism agent. After the load and toxicant shock, the SBR system just adding activated sludge couldn’t come back to original level and the activated sludge micro-ecosystem was frustrated. The applying of microorganism agent increased biological activity and system’s re-sistance ability to load shock and toxicant shock.

Economic integration in North America: Formal, Informal and Spatial Aspects.

An exemination of a series of indicators of economic integration in the western hemisphere (Canada-USA-Latin America) indicates that it is proceeding under the influence of formal trade agreements and informal forces including technological change, multinational firm rationalization and location strategies, etc.

La mondialisation de l'economie et le role de l'Etat.

Cet article examine la nature, les cause et les effets de la globalisation, phenomene tres anciens et tres influence par le changement technologique.

Validación del Cuestionario de Creencias Centrales de los Trastornos de la Personalidad (CCE-TP) en población colombiana

Se construyó un cuestionario para evaluar creencias centrales asociadas con los trastornos de la personalidad, fundamentadas en el Modelo de la Terapia Cognitiva. Se realizó el análisis estructural y la validez de contenido de la prueba en población universitaria de la ciudad de Medellín, Colombia. La muestra fue representativa y elegida al azar a través de un procedimiento polietápico. Un número de 809 estudiantes universitarios contestaron el cuestionario de creencias centrales de los trastornos de la personalidad (CCE-TP). Se realizó un análisis factorial exploratorio de la prueba, reagrupándose los ítems en 14 factores (F) que representan el 61,3% de la varianza. F1: CCE-TP antisocial (8 ítems, a 0,839); F2: CCE-TP esquizotípico/límite (8 ítems, a 0,846); F3: CCE-TP histriónico/patrón seductor (6 ítems, a 0,833); F4: CCE-TP paranoide (6 ítems, a 0,836); F5: CCE-TP por evitación / autopercepción negativa (5 ítems, a 0,755); F6: CCE-TP por dependencia (5 ítems, a 0,797); F7: CCE-TP histriónico/ dependencia emocional (4 ítems, a 0,755); F8: CCETP obsesivo-compulsivo/perfeccionista (4 ítems, a 0,808); F9: CCE-TP por evitación/hipersensible (4 ítems, a 0,766); F10: CCE-TP obsesivo-compulsivo/ crítico frente a los demás (3 ítems, a 0,851); F11: CCE-TP narcisista (4 ítems, a 0,717); F12: CCE-TP pasivo-agresivo / temor a ser dominado (3 ítems, a 0,719); F13: CCE-TP pasivo-agresivo/crítico frente a la autoridad (3 ítems, a 0,685), y F14: CCE-TP esquizoide (2 ítems, a 0,774). El alfa de Cronbach de la prueba fue de 0,931.

Foreign direct investment and exports : the experiences of Vietnam

We examined the implementation statuses of a total of 5,919 foreign direct investment (FDI) projects approved by the Vietnamese Ministry of Planning and Investment since 1988, and compiled a database of actually disbursed FDI in Vietnam. The database covers FDI flows into Vietnam from 23 countries from 1990 to 2004. Using the data, we analyzed the impact of FDI on the exports of Vietnam with gravity equations. The empirical results demonstrate that FDI is one of the major factors driving the rapid export growth of Vietnam. It has significantly facilitated the expansion of Vietnam's exports to FDI source countries. In particular, the empirical analysis shows that a 1 percent increase in FDI inflows will be expected to give rise to a 0.13 percent increase in Vietnam's exports to these countries.

Avaliação comparativa em educação e música entre crianças precoces com comportamento de superprodução e crianças com desenvolvimento típico

Pós-graduação em Educação - FFC