894 resultados para Art. 49, § 3º


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本研究以模拟高原低氧方法,观察低氧作用于大鼠细胞免疫功能以及去甲肾上腺素(NE)对免疫作用的调节机制。实验结果:与对照相比,7km急性低氧24h淋巴细胞转化下降41%(P<0.01);5km低氧暴露时间为7d,20d时,低氧抑制淋巴细胞转化,分别下降34%和60%(P<0.01);侧脑室注入5nmol/LNE,淋巴细胞转化比对照下降29%(P<O.01);7km10h低氧暴露时,侧脑室注入酚妥拉明(phentolamin)25μg/rat则使低氧抑制淋巴细胞转化从42%提高到21%(P<0.05);侧脑室注入5nmol/L NE,血液CRF水平升高,脑室注入酚妥拉明后则降低;7km24h低氧,下丘脑儿茶酚胺水平升高,血液CRF水平也升高;7km10h低氧暴露的脾淋巴细胞加入不同浓度的CRF体外培养,呈现出浓度依赖性淋巴细胞转化下降想象。因而,本研究提示:低氧可抑制淋巴细胞转化,NE参与急性低氧下对大鼠细胞免疫功能的神经内分泌调节,其调节作用可能与CRF有关系。

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Excrement patches of grazing animals play an important role in greenhouse gas (GHG) fluxes due to the high nitrogen (N) and available carbon (C) deposited in small areas, but little information is available for the effect of excrement in the Inner Mongolian grassland (43 26 degrees N, 116 degrees 40'E). To elucidate the effect of grazing sheep urine, fresh dung and compost on fluxes of methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O), a short-term field study (65 days) was carried out in the typical grassland of Inner Mongolia with the optimised closed chamber/GC technique. Compared with the control, cumulative net CH4 consumption decreased 36, 31, and 18% from urine, fresh dung, and compost plots, respectively; net CO2-C output increased by 6.5, 1.5, and 1.2% from urine, fresh dung, and compost treated soil, respectively; about three times as much N2O-N was emitted from urine and the fresh dung treatments during 65 days. Nitrous oxide emission was positively correlated with CO, emission (R = 0.691, P < 0.01) and water-filled pore space (R = 0.698, P < 0.01). The percentages of N2O-N loss of applied-N were 0.44 and 1.05% for urine and fresh dung, respectively. Our results suggest that in autumn in the degraded grassland of Inner Mongolia, the effect of sheep excrement may be ignored when evaluating the total GHG emissions.

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云南金顶铅锌矿是镉元素富集区,采矿活动导致镉元素释放出来进入地表环境造成镉污染。矿区不同岩石中镉分布差异比较大,围岩中镉含量范围在50×10^-6-650×10^-6之间,平均310×10^-6,原生矿中镉含量范围14×10^-6-2800×10^-6,平均767×10^-6,氧化矿中镉含量范围110×10^-6-8200×10^-6,平均1661×10^-6,其平均值最高。氧化矿是镉元素的主要载体和释放源。淋滤实验表明矿石易氧化而释放出镉等有害元素,滤出元素可以迅速发生沉淀或被沉淀物包裹,其能力表现为Zn〉Pb〉Cd。研究结果表明,矿区下游江河段水体中隔的平均值为15.7μg/L,悬浮物中镉平均值为49.3 mg/kg,沉积物中镉平均值为203.7 mg/kg。矿区富镉岩石和矿物的自然风化是造成江水体和沉积物中镉污染的直接原因,对流域水生态环境造成潜在危害.

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辽东五龙地区中生代燕山期侵入岩类在时空上与金矿关系密切。该类侵入岩具有接近的微量元素Th/U、Zr/Hf、Nb/Ta值。随着不同岩石类型中的SiO2、MgO的含量的变化,(^87Sr/^66Sr)i和(^143Nd/^144Nd)i值保持不变,说明岩浆在侵位过程中没有明显受到围岩物质混染,且该类侵入岩有着相同的岩浆源区。Sr、Nd同位素组成表明成岩物质以下地壳为主。三股流花岗岩和矿石有相似的Pb同位家组成,结合含金石英脉(矿体)切穿已固结三股流花岗岩的地质事实,暗示了三股流花岗岩不太可能是直接的矿质提供者,推测成矿物质与成岩物质主体来自深部的同一岩浆源区,金矿成矿是同一岩浆源区岩浆演化不同阶段的产物。

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在西昆仑北缘早前寒武纪变质地层中,笔者等识别出大量不同时代的片麻状花岗岩,其中包括新元古代片麻状花岗岩。获得最新的新元古代片麻状花岗岩的单颗粒锗石SHRIMP年龄为815±57Ma,片麻状花岗岩的岩石学特征反映它们形成于裂解构造背景,结合对区域上新元古代地层及中元古代末期构造事件的研究,笔者认为新元古代片麻状花岗岩反映了古塔里木板块作为Rodinia超大陆一员发生裂解的时间,这对研究古塔里木板块在Rodinia超大陆中的位置及中国Rodinia超大陆裂解的研究提供了重要的地质依据。

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矿产资源开采利用过程中导致的重金属环境污染问题日益严重。我国铅锌矿资源丰富,其开采利用过程中镉的环境污染也日益突出。本文通过对云南兰坪金顶Pb-Zn矿区矿床开采利用过程中镉等重金属元素的环境地球化学行为及矿区生态环境的研究,得出如下主要结论。 1. 矿石淋滤实验表明矿区部分氧化铅锌矿石可以很快被再次氧化或者被溶解并释放出大量镉等有害元素,滤出元素可以迅速发生沉淀或被沉淀物包裹,其释放能力表现为Zn>Pb>Cd。铅锌氧化矿石中菱锌矿组分含量是影响镉淋失的主要因素。在开放体系的水-岩作用下,矿区岩石、矿物的自然风化极易造成当地水系统中镉污染。 2. 矿区不同岩(矿)石中镉含量分布差异比较大,围岩中镉含量为50-650 ppm,平均310 ppm,原生矿中镉含量为14-2800 ppm,平均767 ppm,氧化矿中镉含量为110-8200 ppm,平均1661 ppm,其平均值最高。Zn、Cd地球化学性质的差异导致了二者在原生矿和氧化矿中的不同地球化学分配特点,原生矿Zn/Cd高于氧化矿Zn/Cd,表明氧化环境中镉更容易在氧化矿中富集,而锌更容易被氧化析出到环境中。氧化矿中Cd与Ca呈负相关,这表明Cd的富集和Ca的氧化淋失是同时进行的,并且还可能有Cd对Ca的类质同像代替存在。 3. 矿区上游对照区土壤中的高含量Cd浓度是因土壤母质层重金属高背景值造成的,而非人为污染。矿区中心区土壤受到严重Cd污染,可能与选厂、采场废石堆、尾矿库和露采矿山大范围暴露有关。矿区沿沘江下游两岸土壤中Cd含量远远超出上游土壤背景值和金顶全区土壤背景值,这可能是与污水灌溉有关。通过加权综合污染指数评价法发现矿区土壤污染的主要因子是Cd,其次是Zn和Pb,矿区土壤重金属污染贡献顺序为:Cd>Zn>Pb。矿区土壤污染主要表现为:矿区土壤污染有从中心区向沘江下游扩散区土壤中蔓延的趋势。 4. 矿区水体中出现较高含量的镉,高出天然河流中镉含量的50-100倍。矿区架崖山、北厂和跑马坪等采矿区水体中镉浓度范围在15-30 µg/L之间。矿区水体中镉含量水平表现为:矿山浅层地下水>矿山溪流水>沘江河水。研究结果表明,矿区沘江下游河段水体明显受镉污染,其中水体中镉的平均含量为15.7 µg/L,悬浮物中镉含量为49.3 mg/kg,沉积物中镉含量为203.7 mg/kg。矿区载镉岩石和矿物的自然风化是造成矿区水环境中镉污染的直接原因。 5. 跑马坪采场的废弃石具有较低的Cd含量,而北厂、架崖山采场的废弃石具有较高的Cd浓度,可能与废弃矿石类型本身差异有关。尾矿剖面中的Cd含量,在表层中随剖面深度呈递减趋势,在中层随剖面深度变化不明显,而在底层中明显富集。尾矿库表层尾矿样品中弱酸提取态和可还原态Cd高于底层尾矿样品,相比之下,表层尾矿中Cd等重金属元素易于释放到环境中,对环境的潜在危害大。老尾矿库尾矿砂中Cd金属总量高于新尾矿库尾矿砂,可能还是因为选矿工艺、技术的差异造成的。 6. 矿区污染段水体中硫同位素值较低,远远低于上游非污染区硫同位素值。矿区水体中δ34S值保持了金顶铅锌矿山源区矿山物质硫同位素的特征,显示了矿山来源物质的影响。根据水体硫酸盐中硫同位素稀释原理,研究发现沘江下游水体SO42-中85 %的硫来源于矿山物质。 7. 从矿区筛选出Cd、Zn、Pb的超富集植物共有4种:其中Cd超富集植物有2种,分别是本地生条裂萎陵菜(Potentilla lancinata Card. In Lecomte)和辣子草(Galinsoga parviflora Cav.);Zn超富集植物仅发现有1种植物,为节节草(Equisetum ramosissmum Desf.);Pb超富集植物发现了1种植物,为毛莲菜(Picris hieracioides L.)。这些植物均具备了超富集植物的基本特征,在污染土壤治理与修复方面具有一定的实践意义。 8. 建立了金顶铅锌矿山(床)地质环境模型。Cd的释放、迁移扩散模式为:雨水淋滤时,矿山固体废弃物产生富Cd的酸性或弱酸性矿山排水,通过下渗淋滤发生测向和垂向迁移,进入周边水体和土壤,然后被水系沉积物中针铁矿、方解石等吸附,并在沉降物中沉淀富集,导致矿区主要河流沘江水体的自净能力下降,加速水体的进一步恶化,破坏生物生存环境。矿区受污染水体、土壤和大气中的有害物质通过生物链进入动植物体内,进而危害人类健康。

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High sensation seekers have unusual creativities. Recent years Furnham Adrian et al, found that the groups have different arts tendency have higher difference in Sensation seeking dimension than in Big 5. Some studies found arts students have higher level in many dimension. Sensation seeking has an important influence to peoples` aesthetic conception. This thesis measured art (including painting, music, dancing) students and non-art students` trait of sensation seeking Personality, and looked for the similarities and differences between art students and non-art students in development of sensation seeking personality. Try to find the influence of different procession of art study to sensation seeking level. The outcome of this study: 1. In non-art students, sensation seeking level has a decrease from Grade 1 to Grade 3 in college students, especially in males. Male has higher sensation seeking level than female, especially in TAS, DIS and GEN. 2. There are differences between art students and non-art students in sensation seeking. In ES and GEN Painting students have higher level than non-art students, but in TAS dancing students have lower level than non-art students, in BS students studied in music have lower level than non-art students. 3. Tendency of arts development in art students and non-art students has difference from grade 1 to grade 3. Tendency in non-art students has a decrease, but in art students is not so obviously. The developments in TAS、ES、GEN of painting students, in ES、BS、GEN of dancing students, in TAS、ES、GEN of music major students have differences towards to non-art students. Different art studies have possibility to improve opening of experiment and normal sensation seeking level. All the Different art kinds may affect the development of ES and GEN, and ES and GEN may become commonness gradually within all kind art groups. But this commonness is not so notable in Grade 1-3. 4. Between different art kinds have differences. TAS Scores of dancing group is notably lower than scores of music and painting groups, score of painting group in ES BS and GEN is remarkably higher than that of music and dancing groups, and painting group in DIS has a higher score than music group and dancing group. Painting group has highest sensation seeking in all art kinds students, and dancing group has lowest score in TAS. 5. For female, development tendency of all art kinds dimensions have no remarkable difference, except DIS. Interaction in female DIS dimension may be aroused by scores increase of painting group. In other scores development tendency of different kinds arts have no notable difference.

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Dissertação apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Empresariais

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In 1986, New Zealand responded to the open-access problem by establishing the world's largest individual transferable quota (ITQ) system. Using a 15-year panel dataset from New Zealand that covers 33 species and more than 150 markets for fishing quotas, we assess trends in market activity, price dispersion, and the fundamentals determining quota prices. We find that market activity is sufficiently high in the economically important markets and that price dispersion has decreased. We also find evidence of economically rational behavior through the relationship between quota lease and sale prices and fishing output and input prices, ecological variability, and market interest rates. Controlling for these factors, our results show a greater increase in quota prices for fish stocks that faced significant reductions, consistent with increased profitability due to rationalization. Overall, this suggests that these markets are operating reasonably well, implying that ITQs can be effective instruments for efficient fisheries management. © 2004 Elsevier Inc. All rights reserved.

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The main purpose of this paper is to analyze Hannah Arendt’s citizenship proposal. The central thesis is that this proposal is possible in contemporary democracies, and it is adequate for developing and strengthening of political action. The work is divided in five sections. In the first, we develop a brief introduction on the studied issue. In the second and third section, we analyze, respec-tively, political and moral conditions that enable democratic citizenship, and the conditions that hinder the exercise of the same, according to Arendt. Then, we reflect critically on Arendt’s citizenship proposal. Finally, we conclude and we propose a set of civic challenges relate to current democracies in light of the above proposal.