54 resultados para 6243


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The study investigates the formal integration of English loanwords into the Swedish language system. The aim has been to analyse and describe the morphological/morphosyntactic and the orthographical integration of the loanwords. I have studied how the foreign language elements get accommodated to Swedish and which factors are relevant in the integration. The material for the study consists of Swedish newspapers published in Sweden and Finland in paper format (with a focus on the years 1975 and 2000) and newspapers in digital format on the net. The theoretical frame for the study is contact linguistics. The study is based on a sociolinguistic, structural and language political perspective on what language is, and what language contact is. The method used is usage-based linguistic analysis. In the morphological study of the loanwords, I have made both a quantitative and a qualitative study. I have analysed the extent to which loanwords show some indication of integration in Swedish, and to what extent they show no signs of integration at all. I have also analysed integration in relation to word classes i.e., how nouns, adjectives and verbs integrate and which factors are relevant for the result of the integration. The result shows that most loanwords (36 %) do not show any signs of being formally integrated in Swedish. They undergo neither inflectional, nor derivational changes. One fifth of the loanwords are inflected according to the rules of Swedish grammar. Nouns are generally more often than verbs placed in positions in the sentence where no formal adaption is needed. Almost all of the verbs in the material are inflected according to Swedish rules of grammar. Only 3 % of the loanwords are inflected according to English rules or are placed in an ungrammatical position in the sentence. The orthographical study shows that English loanwords very seldom get adapted to Swedish orthography. Some English vowel and consonant graphemes are replaced with Swedish ones, for example a, ay and ai are replaced with aj or ej (mail → mejl). The study also indicates that morphological integration is related to orthographical integration: loanwords that are inflected according to Swedish grammar are more likely to be orthographical integrated than loanwords that are inflected according to English grammar. The results also shows that the integration of loanwords are affected by mostly language structural factors and language political factors.

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The TSC2 gene, mutated in patients with tuberous sclerosis complex (TSC), encodes a 200 kDa protein TSC2 (tuberin). The importance of TSC2 in the regulation of cell growth and proliferation is irrefutable. TSC2 in complex with TSC1 negatively regulates the mTOR complex 1 (mTORC1) via RHEB in the PI3K-AKT-mTOR pathway and in turn regulates cell proliferation. It shows nuclear as well as cytoplasmic localization. However, its nuclear function remains elusive. In order to identify the nuclear function of TSC2, a whole-genome expression profiling of TSC2 overexpressing cells was performed, and the results showed differential regulation of 266 genes. Interestingly, transcription was found to be the most populated functional category. EREG (Epiregulin), a member of the epidermal growth factor family, was found to be the most downregulated gene in the microarray analysis. Previous reports have documented elevated levels of EREG in TSC lesions, making its regulatory aspects intriguing. Using the luciferase reporter, ChIP and EMSA techniques, we show that TSC2 binds to the EREG promoter between -352 bp and -303 bp and negatively regulates its expression. This is the first evidence for the role of TSC2 as a transcription factor and of TSC2 binding to the promoter of any gene.

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在以前工作基础上,针对腾格里沙漠人工植被区陆气水热传输过程,提出了一个多层陆气耦合模式。特别给出了导水率的计算模型和修正后的根系吸水模式,考虑了结皮层对土壤水分入渗的影响以及植被演化的过程。陆面过程耦合模式分别对大气、植被、土壤作多层划分,以助于细致了解沿度分布的各物理量。同时,利用本模式对中国科学院沙坡头沙漠站人工植被区陆气水热交换过程进行了数值模拟,模拟结果与实测值吻合较好,可为当地合理利用水热资源和沙漠治理提供科学依据。

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Research report based on evidence gained from the DART report.

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从几何光学角度讨论了积分棒的匀光原理,介绍了积分棒在步进扫描投影光刻系统中的应用,分析了积分棒入射光束的数值孔径对刀口狭缝面上光强分布的影响,得到了积分棒尺寸与刀口狭缝面上照明视场的关系,为步进扫描投影光刻系统中积分棒的设计提供了依据。

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Os métodos potenciais são conhecidos como uma ferramenta útil para estudos regionais. Na Ibéria Ocidental, a gravimetria e a magnetometria podem ser utilizadas para auxiliar no entendimento de algumas questões sobre a estruturação tectônica offshore. Nesta região, tanto as estruturas geradas pela quebra continental, quanto às herdadas do embasamento variscano, tem uma importante contribuição para a resposta geofísica regional observada com estes métodos. Este trabalho tem como objetivo correlacionar as feições geofísicas observadas com alguns modelos geológicos do arcabouço tectônico da Ibéria Ocidental já publicados na literatura. Mapas filtrados foram usados para auxiliar no reconhecimento de diferentes assinaturas geofísicas, os quais foram calculados a partir dos mapas de gravidade Bouguer e do campo magnético total tais como o gradiente horizontal total, derivada tilt, derivada vertical, e integral vertical. O domínio crustal continental foi definido a partir da interpretação dos dados gravimétricos, utilizando gradiente de gravidade horizontal total da Anomalia Bouguer. Os dados magnéticos, originais e filtrados, foram utilizados para identificar mais três domínios regionais offshore, que sugerem a existência de três tipos de crosta não-siálica. Dois deles são propostos como domínios de transição. A região da crosta de transição mais próxima do continente tem uma fraca resposta regional magnética, e a porção mais distal é um domínio de anomalia de alta amplitude, semelhante à resposta magnética oceânica. O limite crustal oceânico não pôde ser confirmado, mas um terceiro domínio offshore, a oeste da isócrona C34, poderia ser considerado como crosta oceânica, devido ao padrão magnético que apresenta. Alguns lineamentos do embasamento foram indicados na crosta continental offshore. As feições gravimétricas e magnéticas interpretadas coincidem, em termos de direção e posição, com zonas de sutura variscanas, mapeados em terra. Assim, esses contatos podem corresponder à continuação offshore destas feições paleozoicas, como o contato entre as zonas de Ossa Morena-Zona Centro-Ibérica. Nesta interpretação, sugere-se que a crosta continental offshore pode ser composta por unidades do Sudoeste da Península Ibérica. Isto permite considerar que a Falha de Porto-Tomar pertence a uma faixa de deformação strike-slip, onde parte das bacias mesozoicas da margem continental está localizada.

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兰科植物是被子植物中物种最丰富和最进化的类群之一,具有精巧、多样化的花部结构以及独特的吸引传粉者方式。开展兰科植物传粉生物学的研究对理解自然选择机制和异花授粉优势学说具有重要的理论意义。广西雅长兰科植物自然保护区是我国第一个以兰科植物命名的保护区,本文通过对保护区内同域分布的流苏贝母兰(Coelogyne fimbriata)和兔耳兰(Cymbidium lancifolium )传粉过程观察和繁殖成功等方面的研究,探讨兰科植物传粉机制和防止同株异花授粉的机制。同时结合传粉生物学研究的结果,对兰科植物多样性保护提出相关建议。主要研究结果如下: 1.流苏贝母兰的传粉生物学 在保护区2 个居群内对流苏贝母兰花期物候、传粉者种类和行为进行了连续3 年(2005-2007)的观察,对花和传粉者形态学指标进行了测量,对两个居群内所选取实验样地的花粉移走率、花粉接收率和结实率进行了详细的统计,通过动物行为学实验检测了花香对传粉者吸引方面的影响。并通过人工繁育系统实验检测流苏贝母兰的繁殖特征。结果显示,流苏贝母兰为具有特殊气味且无花蜜的兰科植物,由一种黄胡蜂属(Vespula)昆虫的雌性个体专性传粉,此为第二例由胡蜂专性传粉的具有食源性欺骗机制的兰科植物,且在传粉者行为和吸引机制与第一例存在很大差异。行为学实验显示花香对传粉者具有吸引作用。流苏贝母兰的花期与实验地黄胡蜂的繁殖季节和种群扩张期相吻合,在此期间,为了满足自身和幼虫的需求,黄胡蜂对碳水化合物需求大大增加。推测流苏贝母兰利用了黄胡蜂在繁殖和种群扩张期间需要大量摄取碳水化合物类物质,通过模拟碳水化合物来源(如果实或有花蜜、汁液分泌的植物)的气味,吸引传粉者。居群内花粉移走率、花粉接收率和结实率分别为0.069-0.918,0.025-0.695和0.014-0.069。结实率较低的原因可能与流苏贝母兰的自交不亲和特性和传粉者连续访问造成的同克隆授粉有关。其自交不亲和特性能有效地阻止自交,促进异交,同时蕊喙在接收花粉24 h 内与柱头愈合也能够减少花粉浪费,提高雄性适合度。 2.兔耳兰的传粉生物学 在保护区1 个居群内对兔耳兰进行了连续2 年(2005-2006)的观察和实验。观察发现兔耳兰唯一的传粉者为膜翅目蜜蜂科的中华蜜蜂(Apis cerana cerana)。中华蜜蜂在花内的停留时间为8-71 s。根据观察我们推测兔耳兰可能是通过其唇瓣上无规则的紫栗色小斑点(假蜜导)来吸引中华蜜蜂为其传粉, 属于食源性欺骗方式。在传粉过程中兔耳兰的药帽与花粉团和粘盘一起粘在中华蜜蜂胸背部。药帽的存在能够阻止下一朵被拜访的花实现雌性功能。兔耳兰药帽高度加上传粉昆虫胸高大于传粉通道入口的高度, 支持兔耳兰可能通过药帽来减少同株异花授粉现象的推测。蕊喙会在花粉接受72 h 内逐渐下弯并与柱头愈合,将接受的花粉包裹,且有些花的花萼片和侧面的两个花瓣会环抱住唇瓣侧裂片及蕊柱形成的入口,即传粉通道,避免继续接收花粉,增加花粉输出,提高雄性适合度。2005 和2006 年该兔耳兰居群的自然繁殖成功率分别为0.211 和0.213。繁育系统实验证明兔耳兰是高度自交亲和物种,不存在无融合生殖和自动自花授粉的现象, 其结实依赖传粉者。TTC 法检测结果显示兔耳兰种子活力达85.78%因此推断种子活力不是制约兔耳兰种子萌发的主要原因。而传粉者的密度和访问频率可能是影响兔耳兰结实的重要因素, 并最终影响兔耳兰种群的维持和扩张。 3.兰科植物促进繁殖成功的机制 植物通过各种方式吸引传粉者的最终目的是实现繁殖成功,是植物生活史的重要环节。兰科植物具有雌雄同体的合蕊柱的特殊结构,为了避免花粉-柱头间的干扰,其进化出一系列特殊的花部结构和适应机制,如欺骗性吸引机制、花粉块柄弯曲、花粉干缩等等。流苏贝母兰作为大量开花的克隆植物,其自交不亲和特性是促进异交的重要机制,另外蕊喙在花粉接收24 h 内与柱头发生愈合也是减少同株异花授粉机率的重要花部适应特征。兔耳兰为聚丛状生长的兰科植物,总状花序具多朵花,在传粉过程中通过药帽的阻挡和机械隔离,使携带于昆虫背部的花粉不能进入花内与柱头发生接触,避免同株异花授粉的发生。另外兔耳兰也存在花部适应的机制,蕊喙在花粉接收72 h 内逐渐下弯与柱头愈合,同时有些花的花萼片和侧面的两个花瓣环抱传粉通道入口,避免继续接收花粉,提高雄性适合度。 4. 兰科植物传粉系统和多样性保护 传粉生物学的研究为兰科植物的保护生物学提供了坚固的理论基础和重要的科学依据。绝大部分的兰科植物繁殖成功受到传粉者数量的限制。由于其精巧的花部结构,约67%已知传粉系统的兰科植物仅由唯一的传粉者专性传粉。另外,在某些区域内,还存在着较高程度的传粉者共享。传粉者数量的减少已经威胁到兰科植物的繁殖生存。因此,对兰科植物的保护应不仅仅关注于植物的保护,同时还应致力于传粉系统的保护。

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紫茎泽兰(Eupatorium adenophorum Spreng)是一种原产于墨西哥的恶性杂草。近年来已严重妨碍了云南省甚至整个西南地区、林、牧业的发展。自1984年8月引进泽兰实蝇(procecidochares utilis Stone)开展了生物防治研究。已在云南境内七个地州(市)定殖扩散。为了解泽兰实蝇的控制作用,本文从研究泽从实蝇生态学特性入手。分析了泽兰实蝇生态学特性与紫茎泽兰生物防治的关系。定量地评价了泽兰实蝇的控制作用。并且应用灰色系统中局势决策方法比较了不同环境条件下的生防效果。其主要结果如下:1、泽兰实蝇雌性与雄性成虫的存活曲线均近于Deevery I型;雌雄一并来看。则成虫存活曲线为Deevery II型;雌性成虫的寿命比雄性长。产卵峰期多在产卵开始后的第二到第四天。2、泽兰实蝇幼虫与成虫均存在密度制约。在平均每雌占有两枝供试产卵枝条时产卵量最大。同时孕育虫的后代也最多。3、泽兰实蝇的净增殖率R. = 24.365。内禀增长率r_m = 0.055。周限增长值λ = 1.057。种群加倍时间t = 12.603天,世代周期T = 58.371天。4、泽兰实蝇幼虫种群的空间分布呈聚集型且接近于负二项分布。一般来说平均拥挤度大的地区,对紫茎泽兰的控制效果也好。5、利用计算机模拟术对泽兰实蝇的控制作用进行拟合。较之以寄生率来评价生防效果更为科学,也更为符合客观实际。6、对不同环境下的控制作用进行局势决策可知,温度较高。湿度偏低的地区。生防效果优于那些温度较低或温、温度均较高的地区。在本文所进行调查的几个样地中,泽兰实蝇控制效果大小的次序依次为:元江>宜良>双柏>思茅。

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稠油热采使得地层中的温度发生变化,从而导致地层中流体性质参数在地层中存在一定分布,其中对于无限大稠油藏和圆形稠油油藏中的两区同心圆分布和三区同心圆分布已经研究的比较成熟。但是对于任意形状稠油区域中的径向分布目前研究还较少,而且用一般解析或半解析方法都较难获得理论解。同时随着稠油热采的深入进行,地层温度大多不再是按径向分布的,而且存在部分高温条带。这时用目前所建立的热采试井模型进行解释会产生较大误差,因此建立了热采井数值试井的新方法。主要解决了以下两方面的问题:(1)复杂外边界条件下流体参数呈多区径向分布时的热采井试井资料解释方法问题;(2)复杂边界条件下流体参数呈条带分布时的热采井试井分析方法。所建立的模型已通过其简化形式与解析解进行对比并获得一致性结果。文中给出了现场实际解释的例证。\newline 建立了复杂边界条件下热采井的数值试井模型,并利用非结构化网格生成技术对求解区域进行划分,通过有限元方法计算出了流体参数径向分布和条带分布条件下的试井理论曲线,分析了理论曲线在不同外边界及不同流体参数分布下的特征,以及非牛顿流幂律指数、流度比、热采前缘位置等因素的影响。通过模型简化形式的计算结果与解析解的对比说明了数值计算的正确性,并给出了现场实例分析。分析得到了地层压力、渗透率、热采前缘位置、不同区域的稠油流体参数分布、井筒存储以及表皮效应等参数。\newline 从地下流体渗流场的热-流耦合理论出发,所建立和求解的新的不定常流动模型,解决了稠油油田热采开发过程中,通过油气井单点测试进行地层评价的技术难题,为稠油油田热采开发方案的调整提供了有力的技术保障。

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Knowing that Fe is sensitive to swift heavy ion irradiations whereas Au and Al are not, the behavior of nanometric metallic multilayer systems, like [Fe(3 nm)/Au(x)](y) and [Fe(3 nm)/Al(x)](y) with x ranging between 1 and 10 mn, were studied within the inelastic thermal spike model. In addition to the usual cylindrical geometry of energy dissipation perpendicular to the ion projectile direction, the heat transport along the ion path was implemented in the electronic and atomic sub-systems. The simulations were performed using three different values of linear energy transfer corresponding to 3 MeV/u of Pb-208, Xe-132 and Kr-84 ions. For the Fe/Au system, evidence of appearance of a molten phase was found in the entire Au layer, provided the Au thickness is less than 7 nm and 3 nm for Pb and Xe ions, respectively. For the Fe/Al(x) system irradiated with Pb ions, the Al layers with a thickness less than 4 nm melt along the entire ion track. Surprisingly, the Fe layer does not melt if the Al thickness is larger than 2 nm, although the deposited energy surpasses the electronic stopping power threshold of track formation in Fe. For Kr ions melting does not occur in any of the multilayer systems.

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The transformation field method (TFM) originated from Eshelby's transformation field theory is developed to estimate the effective permittivity of an anisotropic graded granular composite having inclusions of arbitrary shape and arbitrary anisotropic grading profile. The complicated boundary-value problem of the anisotropic graded composite is solved by introducing an appropriate transformation field within the whole composite region. As an example, the effective dielectric response for an anisotropic graded composite with inclusions having arbitrary geometrical shape and arbitrary grading profile is formulated. The validity of TFM is tested by comparing our results with the exact solution of an isotropic graded composite having inclusions with a power-law dielectric grading profile and good agreement is achieved in the dilute limit. Furthermore, it is found that the inclusion shape and the parameters of the grading profile can have profound effect on the effective permittivity at high concentrations of the inclusions. It is pointed out that TFM used in this paper can be further extended to investigate the effective elastic, thermal, and electroelastic properties of anisotropic graded granular composite materials.

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介绍了一个热网分布式计算机监控系统。包括系统设计目标、系统构成、控制策略、系统通讯、软件实现及系统运行环境。该系统在铁煤集团热电厂运行 ,取得了较好的效果