911 resultados para Stylistics of expression


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Objetiva-se, neste trabalho, compreender as lutas de resistência e os poderes que estão em jogo no contexto de manifestações populares de dois mil e treze, no Brasil, realizando uma análise discursiva de duas notícias televisivas. Por meio deste estudo, analisamos a imagem construída acerca dos participantes e suas motivações e entendemos como a grande imprensa retratou as manifestações em contraponto com o que foi apresentado nas novas mídias alternativas, elegendo como entradas linguísticas as designações atribuídas aos eventos e aos seus participantes e as vozes relatadas nas notícias. O estudo que ora se apresenta trata de uma análise do discurso midiático, segundo a teoria da AD de linha francesa, com base, nos postulados de Maingueneau (2008b), através da semântica global proposta pelo autor. Consideramos ainda que uma entrada que privilegia o estudo dos performativos e pressupostos (Rocha, 2014) vem permitindo avanços notáveis nos encaminhamentos de uma perspectiva discursiva. Para fundamentar nossa abordagem teórica, seguiremos a perspectiva dialógica da linguagem (Bakhtin, 2003) e a noção de gêneros do discurso através dos critérios de Maingueneau (2011). Além disso, abordaremos as noções de poder e as lutas de resistência (Foucault, 1979) e a produção de subjetividade por meio dos agenciamentos e das máquinas de expressão (Guattari & Rolnik, 2005). Através de um estudo sobre as imagens no campo midiático, pretendemos desnaturalizar a visão de que o telejornal apresenta a verdade única e concreta em suas notícias, mostrando que essas notícias são apenas uma das diversas perspectivas de realidade possíveis, seguindo os postulados de Wolff (2005). O corpus de análise selecionado foi obtido a partir da página na internet do telejornal, com a retirada dos vídeos das manifestações dos dias vinte e três e vinte e quatro de julho de dois mil e treze, pelo site do Jornal Nacional, da Rede Globo de televisão. Com esses vídeos, poderemos observar que as polêmicas e os posicionamentos discursivos entre as diferentes mídias são evidenciados e perpassam esse evento. Busca-se, enfim, realizar uma análise mais apurada do discurso midiático, que, por sua vez, evidencie a relação entre as modalidades da linguagem: verbal e não verbal e o seu funcionamento. Como resultados, observamos que as notícias podem apresentar um descolamento entre as modalidades da linguagem, ou seja, entre o que é falado e o que é mostrado ao telespectador. Sendo assim, a parte verbal (designações) evidencia um possível equilíbrio entre policiais e manifestantes, diferentemente, do que pudemos identificar na parte não verbal (vozes e imagens) da notícia. Por fim, através desse deslocamento percebemos que a ideia de um aparente equilíbrio entre as partes é mas um efeito produzido pela própria linguagem do que uma evidência empírica exterior à notícia.

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O estudo procuratraçar os contornos gerais do direito ao esquecimento no ordenamento jurídico brasileiro. O direito ao esquecimento consiste em um instrumento eficaz para impedir que a divulgação de fatos passados, destituídos de relevância informativa, venham a impedir o livre desenvolvimento da pessoa humana, na realização autônoma de seu projeto de vida. Apesar de poder ser exercido por qualquer indivíduo, independentemente de sua notoriedade, o direito ao esquecimento não é absoluto edeve ser ponderado com os direitos potencialmente conflitantes, como a liberdade de expressão e direito à informação.Para melhor compreensão dessa difícil ponderação são apresentados os critérios utilizados pela jurisprudência nacional e estrangeira na solução do árduo conflito entre a divulgação das informações e o direito ao esquecimento, em cujo contexto a atualidade da informação emerge como critério preponderante, embora não absoluto, já que fatos de relevância histórica também merecem proteção jurídica. A questão é igualmente examinada no ambiente virtual, a fim de que sejam identificadas as diversas formas de esquecimento na internet, as quais encontram outros meios de efetivação não se restringindo à possibilidade de apagar informações.

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O presente estudo tem por objetivo oferecer uma contribuição inicial para a revitalização do direito eleitoral, por meio da releitura de seus institutos, regras, princípios e lógica estruturante à luz do sistema constitucional da liberdade de expressão. Seu ponto de partida é a constatação de que o direito eleitoral brasileiro não confere à liberdade de expressão a sua devida dimensão de peso. No contexto das campanhas, as liberdades de expressão, informação e imprensa têm sido demasiadamente sacrificadas. O arcabouço teórico do direito eleitoral, ao invés de se estruturar em torno da necessidade de garantir um debate públicodesinibido, robusto e aberto, parece organizar-se exatamente no sentido oposto, buscando limitar o fluxo e a contraposição de informações, ideias e opiniões. O trabalho identifica duas causas principais deste cenário. Em primeiro lugar, e de modo geral, isso se dá porque a cultura da liberdade de expressão não criou raízes no país. Em segundo lugar, e mais especificamente, porque a dogmática do direito eleitoral padece de grave subdesenvolvimento teórico, que se reflete em três principais deficiências: (i) na inexistência de identificação e sistematização consistente dos princípios substantivos norteadores do direito eleitoral e seus respectivos conteúdos, (i) na construção da disciplina sob fundamentos teóricos inconsistentes e contraditórios como o ideal democrático, e (iii) na regulação excessiva, assistemática e casuísta, instituída à margem do sistema de direitos fundamentais. Para a superação dessas deficiências, propõe-se, em primeiro lugar, um marco teórico para a liberdade de expressão, capaz de fornecer o instrumental necessário para a regulação eleitoral.Em seguida, apresenta-se um panorama do tratamento atual da liberdade de expressão no direito eleitoral, procedendo-se à filtragem de grande parte da regulação das campanhas eleitorais à luz do sistema constitucional da liberdade de expressão, incluindo o regramento da propaganda política, o acesso aos meios de comunicação durante o pleito, e as regras de financiamento de campanha.

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O presente trabalho tem como ponto de partida os problemas que podem advir doexercício potencialmente danoso da liberdade de expressão. Desta forma, foram estabelecidas, inicialmente, as premissas sobre as quais se deve fundamentar o Direito Penal no seio de um Estado Democrático de Direito. Posteriormente, foram analisados os contornos do bem jurídico limitado pela eventual intervenção penal, bem como as características e principais formas de manifestação do problema, tendo sido estabelecido, ainda, um panorama do tratamento jurídico-penal conferido ao problema nos Estados Unidos, na Alemanha, na Corte Europeia de Direitos Humanos e no Brasil. Da análise restou comprovado que há uma tendência majoritária à admissibilidade da intervenção penal sobre o problema, limitando discursos potencialmente danosos como forma de promover uma sociedade mais pluralista e tolerante. Partindo-se desta constatação, buscou-se elaborar uma proposta dogmática que possa servir como mecanismo de limitação do poder punitivo, estabelecendo-se critérios minimamente satisfatórios para a aferição da potencialidade lesiva de um discurso. Por fim, apresentou-se uma análise crítica a respeito de tais processos criminalizatórios, já que constituem mera tentativa de promoção de minha exposição valores por meio do Direito Penal, o que não poderia ser admitido num Estado Democrático de Direito.

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O esporte, entre as suas diversas variantes, é meio de expressão das construções acerca da identidade nacional. O futebol atua como um elemento aglutinador de etnias e classes e é uma importante maneira de influenciar a visão que o brasileiro tem de si próprio. No Brasil, a Seleção funciona como instrumento unificador de nação, representante da cultura nacional. Ao representar os atletas e equipe, os meios de comunicação acabam por construir imagens que influenciam nos sentidos de pertencimento em relação ao objeto retratado. Por meio dos discursos adotados pela imprensa, atribuímos valores simbólicos que geram identificação. A disputa de uma Copa do Mundo FIFA é um momento em que o sentimento de nacionalidade é avivado diante da competição entre times de futebol que correspondem a Estados-nação. No entanto, os últimos anos teriam demonstrado uma queda de interesse do torcedor nacional pelo selecionado. O Brasil, por duas oportunidades, foi sede de um Mundial. E, nas duas ocasiões, a Seleção Brasileira sofreu derrotas e não conseguiu conquistar o título jogando em seu território. O trabalho, um estudo sobre Comunicação e Esporte, é uma análise dos textos dos jornais impressos O Globo e Folha na cobertura das Copas do Mundo de 1950 e 2014. Busca-se, uma vez que se percebera o vínculo simbólico entre o conceito de nação e o desempenho da Seleção nacional de futebol, entender como foram construídas as representações da equipe e, consequentemente, dos seus jogadores e quais amostras que podem identificar a relação de aproximação ou afastamento com os torcedores, nas competições que marcaram as duas principais derrotas da Seleção em cem anos de história.

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聚 3 一控基丁酸酯 (Poly – 3 - hydroxybutyrate,PHB) 及其它类型的聚 3-泾基链烷酸醋同属于聚酯类物质 , 是自然界中多种细菌的碳源及能源储备物。这种聚酯的物理化学特性与传统塑料相似 , 并具有生物可降解性 , 如能取代化学合成塑料将减少环境中的塑料废弃物 , 从源头治理 " 白色污染 " 问题。微生物发酵法生产的 PHB 价格过高 , 无法在市场上与化学合成塑料竞争。随着分子生物学的发展 , 人们逐渐将视线转向植物生物反应器。转基因植物能够利用二氧化碳为碳源、太阳能为能源合成目的产物 , 大大降低生产成本 , 为生产具有市场 竞争力的新型生物可降解塑料提供可行途径。在此领域虽然己取得一定进展 , 但远未达到商业化生产水平。大规模商业化生产要求转基因植物能够在确保环 境安全性的前提下高效、稳定地生产 PHB 。本文尝试改善植物中 PHB 的生产体系 ,为环保型塑料早日进入市场作出努力。 1. 由于表达框架中多次使用同一启动子会导致基因沉默 , 本文克隆了另一 种子特异性启动子 nap300, 以替换重复使用的7S启动子,减轻“共抑制”。将 nap300 与 GUS 基因相连进行功能鉴定。荧光检测和组织化学染色的结果都证明此仅 30Obp 的 DNA 序列足以调控基因进行种子特异性表达。尽管 B 盒作为 高度保守区在种子特异性表达中起重要作用 , 位于此处的两个碱基替代型突变 并未使 nap300 的活性明显降低 , 对启动子的时空表达模式也无明显影响。将 nap300 、 7S 分别与 phbA 基因 ( 编码 3-酮硫裂解酶) 相连 , 在相似表达环境中 对二者功能进行比较 , 发现两个启动子表达模式基本相同并在同一时期达到活 性高峰 , 因此 nap300 可用于改善 PHB 合成基因在植物体内的表达调控。通过 对种子特异性启动子的比较可加深对其表达模式的了解 , 为植物基因工程中的 精细调控提供依据。 2. 叶绿体基因工程是随着植物遗传转化技术发展刚刚兴起的生物技术 , 具 有超量表达外源基因 , 为原核基因提供适宜表达环境 , 消除 “位置效应”和基因沉默 , 环境安全性好等优点 , 较更适合用于植物生物反应器方面的研究。本研究在国内率先探讨将叶绿体转化技术引入植物生产生物可降解塑料这一领域 的可行性 ( 国外仅有日本一例 ), 构建了叶绿体转化及表达载体 pTRV-PHB, 通过基因枪法将 PHB 合成相关基因导入烟草叶绿体基因组。转基因烟草顺利达到同质化,其形态和生长发育均无异常。 Northern 点杂交检测表明与 PHB 合成相关的三个基因均能在转录水平表达 , 未出现核转化中经常发生的“基因沉默”现象。通过 RT-PCR 进一步检测表明叶绿体型转基因烟草中目的基因的表达水平明显比核转化植株中相应基因的表达水平高。气相色谱分析确证转基因植株具有合成 PHB 的能力。这些都表明叶绿体转化适合用于转基因植物生产 PHB的研究。虽然叶绿体型转基因烟草中产物含量偏低 , 并未达到预期结果 , 但经进一步改进与完善 , 终将会成功地用于生产高附加值产品的植物基因工程中。 3. 为初步探讨叶绿体转化中在同源重组反应介导下整合外源基因的机理 , 从油菜叶绿体基因组中分离两段序列作为同源片段 , 基因枪法转化烟草 , 结果显示即使供体所含同源片段与受体叶绿体基因组相应区域差异高达 10%, 转化效率也无降低。这一现象的发现有助于促进“通用载体” 的改进 , 扩展叶绿体转化受体范围乃至达到商业化应用水平。 4. 成功地通过二次转化获得整合并表达多基因的转基因烟草 , 缩短了研究周期 , 对相关转基因植物的研究有一定参考价值。本文还优化了油菜转化体系 , 使转基因油菜同时整合三个 PHB 合成相关基因的效率由 7.69% 增加至 16.0% 。 田间试验与产物分析正在进行中。

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以简并引物,利用RT -PCR,克隆了普通小麦和黑麦根系的PO 43-转运子( Trans-porter)基因长约1.2kb的部分cDNA序列。对其与GenBank中的已知序列进行同源性比较,结果表明:(1)小麦与拟南芥、番茄等高等植物的氨基酸水平的同源性为60%~78%; (2)与酵母较低为40%左右,而与丝状真菌和细菌的同源性则<27%; (3)小麦与黑麦的同源性为75%。对其表达特性的研究表明:(1)该基因在根系和茎叶组织中均有表达,但在根系组织中转录产物的累积量显著高于茎叶;(2)磷饥饿条件下,茎叶和根系组织中该基因的表达均增强,但根系组织中增强幅度较大,由此认为该基因产物的功能不只是根系从生长环境中吸收PO 43-,而与PO 43-在植物体内的转运密切相关;(3)磷饥饿5天 后的植株重新供给充足的PO 43-,则该基因的表达在24小时内即显著减弱;(4)分根试验中同株的部分根系生长于磷饥饿(OuM)环境中,而另一部分根系生长于PO 43-充足(250uM)的环境中,这两部分根系中该基因转录产物的积累水平并无显著差异。因此认为植物感受磷饥饿胁迫的信号可能来自植物体内部POi-库的耗竭。此外,用磷讥饿条件下的普通小麦根系mRNA构建了cDNA文库,以克隆的部分序列为探针,从cDNA文库中分离了全长序列。

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Human immunodeficiency virus-1(HIV-1)辅助蛋白在其感染和艾滋病发病过程中起着非常重要的作用.Regulator of expression of virion proteins(Rev)作为HIV-1辅助蛋白之一,可以调节病毒结构蛋白mRNA出核转运和蛋白表达,对于病毒的复制至关重要.为研究Rev蛋白对靶细胞表犁和功能的影响,本实验采用电穿孔的方法,将HIV-1的rev基因导入THP-1细胞,通过流式分选结合G418筛选的方法建立稳定表达Rev蛋白的细胞模型;并通过RT-PCR、荧光观察及流式检测的方法,在mRNA和蛋白两个水平对所建立的细胞模犁进行鉴定.结果证实rev基凶成功导入了THP-1细胞并稳定表达,为后续rev基因产物与细胞相互作用的研究提供了平台.

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作物的抗旱性是一个多基因控制的、极为复杂的数量性状,植物对干旱在分子水平上的差异反应通过植物组织生理和细胞生物学水平,最终表现为植物抗旱性的不同。在我国,旱地农业超过耕地面积的50%,但水资源短缺,因此培育和选育抗旱高产作物是发展节水型农业最有效的途径。 青藏高原气候恶劣、年均降雨量少,也是世界大麦初生起源中心,因而蕴藏了十分丰富的与抗逆相关的种质资源材料,从这些特殊的资源材料克隆抗旱基因,不仅对培育抗旱、优质、高产大麦新品种具有重要理论意义和经济价值,而且对整个作物抗旱基础和育种应用研究都具重大促进作用。 为了筛选青稞(裸大麦,Hordeum vulgare ssp. vulgare)抗旱性材料,本研究选用来自青藏高原不同地区的84份青稞为材料,在叶片失水率(water loss rate, WLR)检测分析的基础上,选择失水率值差异显著的12个品种,通过相对含水量(relative water content, RWC)和反复干旱法评价其抗旱性,并通过植株对干旱胁迫下的丙二醛(MDA)含量和游离脯氨酸(free-proline)含量变化,了解不同抗旱性材料的生理反应特性。选择抗旱性强弱不同的品种各两份进行LEA2蛋白基因(Dhn6基因)、LEA3蛋白基因(HVA1基因)的克隆,比较LEA蛋白结构差异与作物抗旱性之间的关系。同时,对抗旱性不同的青稞品种受到干旱时间不同的失水变化率(dynamics water loss rate, DWLR)进行了检测;对抗旱性不同的青稞对照材料进行2 h、4 h、8 h和12 h的快速干旱处理,通过SYBR Green实时荧光定量RT-PCR技术对Dhn6基因、Dhn11基因、Dhn13基因和HVA1基因在不同抗旱性材料受到不同干旱时间处理后的相对表达水平进行了检测。本研究对LEA蛋白基因在抗旱性不同的青稞材料中的干旱胁迫分子水平上的差异反应进行了研究,也对植物的抗旱机理进行了初步探讨。主要研究结果如下: 1. 青稞苗期进行离体叶片失水率测定结果表明,来自青藏高原的84份青稞材料的WLR在0.086~0.205gh-1g-1DW之间。选择WLR低于0.1gh-1g-1DW和WLR高于0.18gh-1g-1DW的品种各6份,并对苗期分别进行未干旱及干旱12小时的处理。相对含水量检测结果表明,低失水率青稞材料干旱后的具有更高的相对含水量,盆栽缺水试验也显示叶片失水率低的材料耐旱能力强于失水率高的材料。通过水合茚三酮法测定离体叶片游离脯氨酸的含量,结果表明,所有品种未干旱处理时,游离脯氨酸含量差异不大(17.10~25.74 µgg-1FW);干旱12小时后,低失水率的品种游离脯氨酸含量明显增高(32.99~53.45µgg-1FW),高失水率品种的游离脯氨酸含量与干旱前变化不明显(P<0.05)。硫代巴比妥酸法测定离体叶片丙二醛(MDA)含量,结果显示,12份所选对照品种中,丙二醛的含量在0.97~2.74nmolg-1FW,干旱12小时后丙二醛的含量显著上升(1.46~4.74nmolg-1FW),高失水率的6个品种的丙二醛含量在未干旱和干旱处理时都明显高于低WLR品种。本研究结果表明青稞的低失水率、低丙二醛含量、高相对含水量和高脯氨酸含量具相关性(P<0.05)。综上研究,我们认为作物失水率的测定可以作为快速检测作物抗旱性的指标之一,因此,强抗旱品种喜玛拉10号(TR1)、品比14号(TR2)和弱抗旱品种冬青8号(TS1)、QB24 (TS2)被选作抗旱基因克隆和表达分析的研究材料。 2. 高等植物胚胎发育晚期丰富蛋白(late embryogenesis abundant proteins, LEA proteins)与植物耐脱水性密切相关,为了探讨青稞LEA蛋白结构差异性与植物抗旱性的关系,本研究以强抗旱品种(喜玛拉10号、品比14号)和弱抗旱品种(冬青8号、QB24)为材料,利用同源克隆法,通过RT-PCR,分别克隆了与抗旱性密切相关的Dhn6基因和HVA1基因。Dhn6基因序列分析结果表明,强抗旱品种品比14号和弱抗旱品种冬青8号Dhn6基因所克隆到的序列为1026bp,它们之间只有5个碱基的差异;喜玛拉10号和QB24克隆到的序列长963bp。在强弱不同的抗旱品种中有22个核苷酸易突变位点,相应的脱水素氨基酸序列推导结果表明,22个核苷酸突变位点中,仅有8个位点导致相应的氨基酸残基的改变,其余的位点系同义突变,另外,21个富含甘氨酸序列的缺失并没有联系作物抗旱性特征。推测这些同义突变位点的氨基酸残基对维持青稞DHN6蛋白的正常结构和功能起着非常重要的作用,也可能DHN6蛋白对青稞长期适应逆境胁迫和遗传进化的结果。对HVA1基因的序列分析结果表明,冬青8号、QB24、品比14号和喜玛拉10号的目的基因核苷酸序列全长分别为661bp、697bp、694bp和691bp,它们都包含1个完整的开放阅读框。相应的LEA3蛋白氨基酸序列结果表明,11个高度保守的氨基酸残基组成基元重复序列的拷贝数与青稞抗旱性之间没有必然关系,在强抗旱品种(喜玛拉10号、品比14号)中三个共同的氨基酸突变位点Gln32、Arg33和Ala195可能对抗旱蛋白的结构和功能有影响;另外,强抗旱青稞品种LEA3蛋白质中11-氨基酸保守基元序列拷贝数和极性氨基酸占蛋白的比例更高,推测LEA3蛋白中基元序列拷贝数和极性氨基酸占蛋白的比例对该蛋白的结构和功能影响更大。 3. LEA蛋白基因的表达水平的上调与植物的耐脱水性密切相关,我们对强抗旱性材料(喜玛拉10号、品比14号)和弱抗旱材料(冬青8号、QB24)进行干旱处理2 h、4 h、6 h、8 h和10 h的失水变化率进行测定,结果表明弱抗旱品种在2~4小时之间失水率变化最明显,而四个对照品种的失水率在8小时后和24小时的失水率值变化不大。进一步提取青稞苗期进行2 h、4 h、8 h和12 h的干旱处理后的总RNA,通过SYBR Green实时荧光定量RT-PCR技术对青稞脱水素基因(Dhn6、Dhn11和Dhn13)和LEA3蛋白基因(HVA1)的相对表达水平受干旱时间和作物抗旱性的影响进行了检测。研究发现,抗旱性不同的青稞品种随干旱处理的时间延长,Dhn6、Dhn11、Dhn13和HVA1基因的相对表达水平不同。 Dhn6基因的相对表达水平在强抗旱青稞品种干旱8小时后快速上升,但在弱抗旱青稞品种干旱处理12小时后检测到更高表达量;Dhn11基因在对照青稞抗旱品种的表达累积水平随干旱时间的延长持续下降;整个干旱过程中,Dhn13基因的相对表达水平在弱抗旱品种持续上升,在强抗旱品种中干旱处理8小时快速上升并达到最高,干旱12小时后降低。与脱水素基因相比较,强抗旱青稞品种在干旱2小时后HVA1基因的相对表达水平显著升高,相对表达量随干旱处理的时间持续上升,在干旱12小时后达到最高;与之相比较,在整个干旱过程中,弱抗旱品种的相对表达水平显著低于强抗旱品种,在干旱8小时之前弱抗旱品种的相对表达水平变化不明显;在干旱8~12小时后却显著上升。上述结果表明,不同的LEA蛋白在植物耐脱水过程中的干旱表达累积水平不同;干旱不是诱导高等植物Dhn11基因表达的主要因素;植物的抗旱性不同,不同LEA蛋白基因对干旱的反应有差异。推测某些LEA蛋白基因的干旱胁迫早期表达累积程度与植物的抗旱性直接相关;其中,Dhn11基因和Dhn12基因不同的表达模式可能与干旱调控表达顺式作用成分(dehydration responsive element, DRE)的有无或结构上的差异有关。 本研究结果认为,(1)失水率和相对含水量可作为植物抗旱性检测的指标之一;(2) DHN6同义突变位点的氨基酸残基对维持该蛋白的正常结构和功能起着重要作用;(3) 11-氨基酸保守基元序列拷贝数和极性氨基酸的比例对LEA3蛋白结构和功能有重要影响;(4)LEA蛋白表达随着干旱胁迫程度而增加,但Dhn11基因并不受干旱诱导表达;(5)作物的抗旱性不同,LEA蛋白对干旱的累积反应并不相同,干旱早期LEA蛋白的累积程度可能会影响植物的抗旱性。 Drought resistance was a complex trait which involved multiple physiological and biochemical mechanisms and regulation of numerous genes. Because its complex traits, it is difficult to understand the mechanisms of drought resistance in plants. Plants respond to water stress through multiple physiological mechanisms at the cellular, tissue, and whole-plant levels. Tibetan hulless barley, a pure line, is a selfing annual plant that has predominantly penetrated into the Qinghai-Tibetan Plateau and remains stable populations there. The wide ecological range of Tibetan hulless barley differs in water availability, temperature, soil type and vegetation, which makes it possess a high potential of adaptive diversity to abiotic stresses. This adaptive genetic diversity indicates that the potential of Tibetan hulless barley serves as a good source for drought resistance alleles for breeding purposes. 12 contrasting drought-tolerant genotypes were selected to measure relative water content (RWC), maldondialdehyde (MDA) and proline content, based on values of water loss rate (WLR) and repeated drought methods from Tibetan populations of cultivated hulless barley. As a result of the screening, sensitive and tolerant genotypes were identified to clarify relationships between characteristics of LEA2/LEA3 genes sequences and expression and drought-tolerant genotypes, associated with resistance to water deficit. In addition, dynamics water loss rate (DWLR) was measured to observe the changes on diffrential drought-tolerant genotypes. Real-time quantitative RT-PCR was applied to detect relative expression levels of Dhn6, Dhn11, Dhn13 and HVA1 genes in sensitive and tolerant genotypes with 2 h, 4 h, 8h and 12 h of dehydration. In the present study, differential sequences and expression of LEA2/LEA3 genes were explored in Tibetan hulless barley, associated with phenotypically diverse drought-tolerant genotypes. 1. The assessments of WLR and RWC were considered as an alternative measure of plant water statues reflecting the metabolic activity in plants, and the parameters of MDA and proline contents were usually consistent with the resistance to water stress. The values of detached leaf WLR of the tested genotypes were highly variable among 84 genotypes, ranging from 0.086 to 0.205 g/h.g DW. The 12 most contrasting genotypes (6 genotypes with the lowest values of WLR and 6 genotypes with the highest values of WLR) were further validated by measuring RWC, MDA and free-proline contents, which were well watered and dehydrated for 12 h. Results of RWC indicated that the values of 12 contrasting genotypes RWC ranged from 89.94% to 93.38% under condition of well water, without significant differences, but 6 genotypes with lower WLR had higher RWC suffered from 12 h dehydration. The results indicated that lower MDA contents, lower scores of WLR and higher proline contents were associated with drought-tolerant genotypes in hulless barley. Remarkably, proline amounts were increased more notable in 6 tolerant genotypes than 6 sensitive genotypes after excised leaves were dehydrated for 12 h, with control to slight changes under condition of well water. Results of MDA contents showed that six 6 tolerant genotypes had lower MDA contents than the 6 sensitive genotypes under both stressed and non-stressed conditions. As a result of that screening, drought- resistant genotypes (Ximala 10 and Pinbi 14) and drought-sensitive genotypes (Dongqing 8 and QB 24) were chosen for comparing the differential characteristics of LEA2/LEA3 genes and their expression analysis. It was conclusion that measurements of WLR could be considered an alternative index as screening of drought-tolerant genotypes in crops. 2. Late embryogenesis abundant (LEA) proteins were thought to protect against water stress in plants. To explore the relationships between configuration of LEA proteins and phenotypically diverse drought-tolerant genotypes, sequences of LEA genes and their deduced proteins were compared in Tibetan hulless barley. Results of comparing Dhn6 gene in Ximala 10 and QB24 indicated that absence of 63bp was found, except that only 5 mutant nucleotides were found. While 22 mutant sites were taken place in Dhn6 gene between sensitive and tolerant lines, 14 synonymous mutation sites appeared in the contrasting genotypes. The additional/absent polypeptide of 21 polar amino acid residues was not consistent with phenotypically drought-tolerant genotypes in hulless barley. It was deduced that synonymous mutation sites would play important roles in holding out right configurations and functions on DHN6 protein. The sequencing analysis results indicated that each cloned HVA1 gene from four selected genotypes contained an entire open reading frame. The whole sequence of HVA1 gene from Dongqing 8, QB24, Pinbi 14 and Ximala 10 was respectively 661bp, 697bp, 694bp and 691bp. Results of DNA sequence analyses showed that the differences in nucleotides of HVA1 gene in sensitive genotypes were not consistent with that of tolerant genotypes, except for absence of 33 nucleotides from +154 to +186 (numbering from ATG) in QB24. Database searches using deduced amino acid sequences showed a high homology in LEA3 proteins in the selected genotypes. Multiple sequence alignments revealed that LEA3 protein from Dongqing 8 was composed of 8 repeats of an 11 amino acid motif, less the fourth motif than Pinbi 14, Ximala 10 and QB24. Consistent mutant amino acid residues appeared in contrasting genotypes by aligning and comparing the coding sequence region, including Gln32, Arg33 and Ala195 in tolerant genotypes as compared to Asp32, Glu33 and Thr195 (Thr184 in Dongqing 8) in sensitive lines. It was concluded that consistent appearance of Gln32, Arg33 and Ala195 would contributed to functions of LEA3 protein in crops, as well as higher proportion of 11-amino-repeating motifs and polar amino acid residues. 3. Most of the LEA genes are up-regulated by dehydration, salinity, or low temperature, are also induced by application of exogenous ABA, which increases in concentration in plants under various stress conditions and acts as a mobile stress signal. Higher levels of proteins of LEA group 3 accumulated was correlated well with high level of desiccation tolerance in severely dehydrated plant seedlings. Dehydrins (DHNs), members of LEA2 protein, are an immunologically distinct protein family, and Dhn genes expression is associated with plant response to dehydration. Dynamic water loss rate was measured between sensitive genotypes and tolerant genotypes after they were dehydrated for 2 h, 4 h, 6h and 8 h. Detailed measurements of WLR at the early stage of dehydration (2, 4, 6, and 8 h) showed that WLR was stabilizing after 8 h, and there were no significant changes between these values and WLR after 24 h. Drought stress was applied to 10-day-old seedlings by draining the solution from the container for defined dehydration periods. Leaf tissues of the selected genotypes were harvested from control plants (time 0); and after 2, 4, 8, and 12 h of dehydration. Differential expression trends of Dhn6, Dhn11, Dhn13 and HVA1 genes were detected in phenotypically diverse drought-tolerant hulless barleys, related to different time of dehydration. Results of quantitative real-time PCR indicated that relative level of HVA1 expression was always higher in tolerant genotypes, rapidly increasing at the earlier stages (after 2-4 h of dehydration). However, HVA1 expressions of sensitive genotypes had a fast increase from 8 h to 12 h of stress. Significant differences in expression trends of dehydrin genes between tolerant genotypes and sensitive lines were detected, mainly in Dhn6 and Dhn13 gene, depending on the duration of the dehydration stress. The relative expression levels of Dhn6 gene were significantly higher in tolerant genotypes after 8 h dehydration, by control with notable higher expression levels after 12 h water stress in sensitive ones. The relative expression levels of Dhn13 gene tended to ascend during exposure to dehydration in drought-sensitive genotypes. However, fluctuate trends of Dhn13 expression level were detected in drought-resistant lines, including in lower expression levels of 12 h dehydration as compared to 8 h water stress. It was conclusion that (1) diverse LEA proteins would play variable roles in resisting water stress in plants; (2) expression of Dhn11 gene was not induced by dehydrated signals because of the trends of expression descended in contrasting genotypes suffered from water deficit and (3) variable accumulations on LEA proteins would be appear in diverse drought-tolerant genotypes during dehydrations. It is deduced that higher accumulations of Dhn6 and Dhn13 expression in 8 h dehydration are related to diverse drought-tolerant lines in crops. The present results indicated that different dehydrin genes would play variable functional roles in resisting water stress when plants were suffered from water deficit. The authors suggest physiologically different reactions between resistant and sensitive genotypes may be the results of differential expression of drought-resistant genes and related signal genes in plants. In addition, contrarily induced expression of Dhn11 and Dhn12 was related to dehydration responsive element (DRE) in barleys. The present study indicated that (1) measurements of WLR and RWC could be considered as one index of drought-tolerant screenings; (2) synonymous mutation sites would play important roles in holding out right configurations and functions on DHN6 protein, (3) higher proportion of 11-amino-repeating motifs and polar amino acid residues would contribute to functions on LEA3 protein, (4) the longer drought, the more accumulation on LEA proteins, except for Dhn11 gene in crops and (5) differential responses on expression of LEA protein genes would result in physiological traits of drought tolerance in plants.

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卵泡抑素(Follistatin)是1987年由Robertson和Ueno分别从牛和猪的卵泡液中分离出的一种富含半胱氨酸的糖基化单链多肽。FS对不同类型的细胞有广泛的调节作用,具有多方面的生物学作用。本研究克隆到牙鲆Follistatin基因,并利用RT-PCR和原位杂交对其在胚胎及成体中的表达进行了分析,并对其启动子进行了组织特异性分析。 1. Follistatin基因组全长4.3 kb左右,其中启动子区长约1 kb。与cDNA序列的比较显示该基因含有5个外显子和4个内含子,内含子和外显子的交界处严格遵守GT…AG规则。Follistatin基因编码了一个含有323个氨基酸的蛋白质前体,该蛋白质前体含有信号肽区域、N-端结构域、Follistatin结构域Ⅰ、Follistatin结构域Ⅱ、Follistatin结构域Ⅲ和C-端结构域。蛋白比较分析表明Follistatin与其他物种的Follistatin的同源性较高,其结构域保守性更高。 三级预测结果显示:在空间构型上,牙鲆Follistatin基因与斑马鱼Follistatin基因完全一致。在序列上高度保守的半胱氨酸在空间上两两相对,它们可能对维持Follistatin蛋白的空间结构起着重要的作用 2. RT-PCR方法和原位杂交方法研究Follistatin基因在牙鲆胚胎中的表达情况结果显示:Follistatin基因在受精后26 hrs开始在中胚层细胞处表达,其后在受精后28、30、32、34、36、38、40、42 hrs等时期Follistatin基因持续表达,并在体节腹部部位、头部,背部体节等部位表达。以MyoD为对照而进行的双色原位杂交结果显示:Follistatin与MyoD在胚胎的体节处表达有重叠区域,对双色原位杂交样品进行的冰冻切片实验结果显示:两个基因的表达区域交叉,互相混合,表明Follistatin基因也在肌肉前体细胞中表达,但并不在所有的前体细胞中表达,Follistatin可能在肌肉发育早期起一定的作用。成体组织中,Follitatin基因在体肾、肠、心脏、头肾、脾中有表达,而在肌肉中没有表达。 3.启动子序列分析结果表明:牙鲆启动子存在AP-1、C/EBP、SP1、USF、E47、MyoD等转录因子的潜在结合位点。显微注射结果显示:该基因启动子能够使绿色荧光蛋白表达在斑马鱼的胚胎肌肉组织中。

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It is easy to find that, in each language, the terms and phrases for the representation of spatial locating and orientation, and the ways for sharing spatial knowledge are very rich. The basic way of sharing spatial information is mapping our experience and actions with the environment by using terms and utterances that represent spatial relations. How to build the mapping relation among them and what factors affect the process of mapping are the questions need to be answered in this study. The whole course of expressing projective spatial relation includes the verbal expression and perception to the projective spatial relation. In experiment 1, the perceptual characteristics of perceiving the projective spatial relation was studied by analyzing the production latencies from the presentation of the stimulators in different directions (at 5 levels: 00, 22.50, 450, 67.50, and 900) to the onset of the corresponding buttons triggering on the keyboard, the study verifies the results of prior researches and revealed the foundation of expressing the projective spatial relation. In the experiment 2, and 3, the way and the role of the verbal expression were investigated. Subjects were asked to speak out the spatial relation between intended object and reference object by using verbal locative expressions. In experiment 2, Chinese was used as the verbal expression way, and in Experiment 3, English instead. Experiment 4 was similar as experiment 3, but time of voice key triggering was controlled and balanced among trials to verify the results of Experiment 3 further. Experiment 5 investigated the effect of pre-cue on the courses of expressing projective spatial relation. There were two kinds of clues, one was the spatial locative utterances, and the other was the perceptual coordinates framework, such as drawing a cross ”+” in a circle to imply four quadrants. The main conclusions of this research were as follows: 1. When speaking out a spatial relation, different sets of spatial terms, such as “left and right”, or “north and south”, affected the speed of verbal expression. Verbal coding process was affected by how well the perceptual salient direction matched with spatial terms, which made the speed of verbal expression different. 2. When using composite spatial terms to express diagonal directions, people tend to use direct mapping from spatial conceptual representation to composite spatial terms, rather than combining the two axes, which implied there existed direct one-on-one mapping between spatial conceptual representation and spatial terms. But during specific developing period, the way of combining two axes was employed as well for spatial expression, which meant perceptual salient directions played critical role in the process of perceiving and expressing projective spatial relations. 3. The process of verbal expression of the projective spatial relation was improved by the familiarity of spatial utterances, but this improvement was not the results of enhancement of the effect of prototypical diagonal direction.

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AIM: To evaluate the suitability of reference genes in gastric tissue samples and cell lines.METHODS: the suitability of genes ACTB, B2M, GAPDH, RPL29, and 18S rRNA was assessed in 21 matched pairs of neoplastic and adjacent nonneoplastic gastric tissues from patients with gastric adenocarcinoma, 27 normal gastric tissues from patients without cancer, and 4 cell lines using reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR). the ranking of the best single and combination of reference genes was determined by NormFinder, geNorm (TM), BestKeeper, and DataAssist (TM). in addition, GenEx software was used to determine the optimal number of reference genes. To validate the results, the mRNA expression of a target gene, DNMT1, was quantified using the different reference gene combinations suggested by the various software packages for normalization.RESULTS: ACTB was the best reference gene for all gastric tissues, cell lines and all gastric tissues plus cell lines. GAPDH + B2M or ACTB + B2M was the best combination of reference genes for all the gastric tissues. On the other hand, ACTB + B2M was the best combination for all the cell lines tested and was also the best combination for analyses involving all the gastric tissues plus cell lines. According to the GenEx software, 2 or 3 genes were the optimal number of references genes for all the gastric tissues. the relative quantification of DNMT1 showed similar patterns when normalized by each combination of reference genes. the level of expression of DNMT1 in neoplastic, adjacent non-neoplastic and normal gastric tissues did not differ when these samples were normalized using GAPDH + B2M (P = 0.32), ACTB + B2M (P = 0.61), or GAPDH + B2M + ACTB (P = 0.44).CONCLUSION: GAPDH + B2M or ACTB + B2M is the best combination of reference gene for all the gastric tissues, and ACTB + B2M is the best combination for the cell lines tested. (C) 2013 Baishideng Publishing Group Co., Limited. All rights reserved.

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Summary Background Reflective writing is a mandatory part of nurse education but how students develop their skills and use reflection as part of their experiential learning remains relatively unknown. Understanding reflective writing in all forms from the perspective of a student nurse is therefore important. Objectives To explore the use of reflective writing and the use of poetry in pre-registered nursing students. Design A qualitative design was employed to explore reflective writing in pre-registered nursing students. Setting A small university in Scotland. Participants BSc (Hons) Adult and Mental Health Pre-registration Student Nurses. Methods Two focus groups were conducted with 10 student nurses during March 2012. Data was analysed thematically using the framework of McCarthy (1999). Results Students found the process of reflective writing daunting but valued it over time. Current educational methods, such as assessing reflective accounts, often lead to the ‘narrative’ being watered down and the student feeling judged. Despite this, reflection made students feel responsible for their own learning and research on the topic. Some students felt the use of models of reflection constricting, whilst poetry freed up their expression allowing them to demonstrate the compassion for their patient under their care. Conclusions Poetry writing gives students the opportunity for freedom of expression, personal satisfaction and a closer connection with their patients, which the more formal approach to reflective writing did not offer. There is a need for students to have a safe and supportive forum in which to express and have their experiences acknowledged without the fear of being judged.

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Clarke, S. M., Mur, L. A. J., Wood, J. E., & Scott, I. M. (2004). Salicylic acid dependent signaling promotes basal thermotolerance but is not essential for acquired thermotolerance in Arabidopsis thaliana. The Plant Journal, 38(3), 432-447. Sponsorship: BBSRC RAE2008

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Dissertação apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências da Educação: Educação Especial, área de especialização em Domínio Cognitivo e Motor