植物耐盐研究进展

从盐胁迫对植物生长发育及生理代谢的影响,植物的耐盐机理以及利用基因工程手段改良作物耐盐性等方面,对近年来植物耐盐研究的一些进展进行了综述,并对植物耐盐研究进行了展望.     

植物耐盐相关基因克隆与基因工程的研究进展(综述)

盐渍化是影响植物生长和发育的主要环境因素之一,而基因工程为耐盐新品种的选育通过了一条新途径。很多耐盐基因已经被克隆和详细研究。笔者就与耐盐性相关的渗透调节物质合成关键基因、盐胁迫信号传导以及与相关的调控元件和因子的克隆及其基因工程应用的研究进展作了概述,以期为相关人员的研究提供参考。     

作物耐盐性的分子生物学研究进展

本文从作物耐离子胁迫、耐渗透胁迫和细胞编程性死亡调节三个方面概述了作物耐盐的生理生化机制;介绍了目前利用分子生物学技术克隆与植物耐盐相关的基因,并根据作物的耐盐机理,对这些与耐盐相关的基因进行了分类;总结分析了转耐盐基因植物的研究现状及其转基因植物的耐盐生状况,并提出了利用转基因技术,改良植物耐盐性的方法和对策。     

植物耐盐的生理生态适应性研究进展

 植物耐盐机制的研究对盐渍土改良利用和选育培育耐盐植物新品种具有重要意义。盐分胁迫下,植物表现一系列生理生态适应性变化。根据近年来对植物耐盐的研究,本文重点阐述了植物体内渗透调节、抗氧化酶活性、光合途径的转变、激素信号转导、植物体内相关蛋白的高表达、形态结构的改变等耐盐的生理生态适应性机制。进一步分析表明,植物耐盐的适应性受多方面调节和控制,应该把多方面的因素都联系起来综合考虑。     

耐盐分胁迫的生物学机理及其基因工程研究进展

介绍了盐分胁迫对植物的伤害、植物耐盐的生物学机理以及通过基因工程改良作物耐盐性的研究进展     

黄河三角洲地区耐盐植物研究进展与展望

黄河三角洲地区土壤盐碱化程度高,引进耐盐植物改良该地区盐碱地是一种"治标又治本"的办法.但耐盐植物种类繁多,耐盐机制复杂,盲目引种只能加重生态破坏,因此,加强黄河三角洲地区盐碱地现状调查研究,改良培育适宜的耐盐植物是目前研究的重点.本文综述了黄河三角洲地区现状、耐盐植物种类特点、耐盐机制以及目前研究存在的问题和解决方法,为黄河三角洲地区耐盐植物的研发及盐碱地植物改良提供理论支持.     

植物耐盐突变体筛选与耐盐转基因研究

随着土壤盐渍化的日益加剧,农业生产的可持续发展受到威胁.人们从改良盐渍土和植物耐盐育种两个方面寻求解决问题的途径.对现有植物物种进行耐盐性筛选和利用现代生物技术创造新的耐盐品种是进行植物耐盐育种的两种主要方法.随着对植物耐盐分子机制研究的不断深入和转基因技术的不断完善,利用现代生物技术方法培育高效耐盐作物品种已成为当今的研究热点.本文对近年来有关植物耐盐突变体筛选、耐盐相关基因的克隆和转基因研究进行了分析讨论.     

植物耐盐性研究进展

对近年来植物在盐环境下所受的伤害和植物的耐盐机理的相关研究作一综述,以期为深入揭示植物耐盐机理,筛选耐盐植物新品种提供参考依据.     

植物液泡膜H~+-Pyrophosphatase基因功能研究进展

植物液泡膜H+-PPase是一种区别于H+-ATPase的质子泵,广泛存在于生物体内.该文重点介绍植物液泡膜H+-PPase基因及同源基因的结构和功能方面的研究进展,以及该基因在不同植物上遗传转化体系的建立,并展望了该基因应用于植物耐盐抗旱基因工程中的前景.     

生命科学及其相关学科研究取得的新成果

简要介绍了生命科学及其相关学科研究取得的成果,包括运用遗传工程使玉米产出特殊蛋白、运用基因工程培育耐寒耐盐植物、在猪体内导入外源基因而减少脂肪增加瘦肉、运用现代生物技术破案、转基因分子治癌、攻克乙肝研究及降低器官移植排斥反应等。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.