994 resultados para Caselius, Johannes, 1533-1613


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Many species of reef f ish agg regate seasonally in large numbers to spawn at predictable times and sites (Johannes, 1978; Sadovy, 1996; Domeier and Colin, 1997). Although spawning behavior has been observed for many reef fish in the wild (Wicklund, 1969; Smith, 1972; Johannes, 1978; Sadovy et al., 1994; Aguilar Perera and Aguilar Davila, 1996), few records exist of observations on the courtship or natural spawning for the commercially important family Carangidae (jacks) (von Westernhagen, 1974; Johannes, 1981; Sala et al., 2003). In this study, we present the first observations on the natural spawning behavior of the economically-valuable permit (Trachinotus falcatus)(Linnaeus, 1758) from the full to new moon period at reef promontories in Belize, with notes on the spawning of the yellow jack (Carangoides bartholomaei) (Cuvier, 1833), and the courtship of five other carangid species.

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The exploitation of California sea lions, Zalophus californianus, in Mexican waters can be divided into four periods as defined by political characteristics of the country: Prehispanic, Colonial, Independent, and Postrevolutionary. During the first period (pre 1533), Native Americans took sea lions at low levels. During the second (1534–1821) and the third (1822–1911) periods, most exploitation was by foreigners and was incidental to other marine mammal harvests. During the Postrevolutionary period (after 1911), sea lions were exploited by Mexican and U.S. citizens for several commercial uses. Exploitation officially ended in 1982, although some small-scale poaching still occurs.

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Toda a reflexão sobre os gêneros literários desenvolvida ao longo da história do Ocidente acaba, de uma maneira ou outra, por afirmar uma dualidade de procedimentos compositivos, os quais estruturam os mais diversos gêneros literários historicamente constituídos: os procedimentos de narrar e descrever. Enquanto o primeiro incorpora o aspecto temporal da experiência humana, com ênfase na causalidade, hierarquia, universalidade e subordinação de partes a um todo, o segundo incorpora o aspecto espacial da experiência humana, com ênfase na aleatoriedade, liberdade, particularidade e permutação coordenativa de partes integrantes de um todo. Narração e descrição, com qualidades estilísticas bem particulares, veiculam visões de mundo antitéticas, porém complementares. Já que dizem respeito mais ao sentido último das obras, podem ser chamadas de princípios morfossemânticos de construção das obras literárias. Todavia, ocorre que esses princípios não abarcam todos os aspectos diferenciadores das obras. Do mesmo modo como se dá ao nível do sentido último do texto, a dualidade universal/particular se reproduz na própria materialidade da linguagem, instaurando a diferença entre estruturas de elocução regular e estruturas de elocução irregular. Esse, afinal, é o cerne da diferenciação canônica entre obra lírica e obra épica, a primeira mais irregular, a segunda mais regular. Trata-se, aí, dos princípios morfológicos de construção das obras literárias. As duas ordens de princípios convergem, de maneira que a narração está para a regularidade do mesmo modo como a descrição está para a irregularidade

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The noble gas sensor using multiple ZnO nanorods was fabricated with CMOS compatible process and sol-gel growth method on selective area and gas response characteristics to NO2 gas of the sensor device were investigated. We confirmed the sensors had high sensitive response denoted by the sensitivity of several tens for NO2 gas sensing and also showed pretty low power consumption close to 20 mW even though the recovery of resistance come up to almost the initial value.

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Understanding the energy dissipation mechanisms in single-crystal silicon MEMS/NEMS resonators are particularly important to maximizing an important figure of merit relevant for miniature sensor and signal processing applications: the Quality factor (Q) of resonance. This paper discusses thermoelastic dissipation (TED) as the dominant internal-friction mechanism in flexural mode MEMS/NEMS resonators. Criteria for optimizing the geometrical design of flexural mode MEMS/NEMS resonators are theoretically established with a view towards minimizing the TED for single-crystal silicon MEMS/NEMS flexural mode resonators.

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This paper describes the growth of Carbon Nanotubes (CNTs) both aligned and non-aligned on fully processed CMOS substrates containing high temperature tungsten metallization. While the growth method has been demonstrated in fabricating CNT gas sensitive layers for high temperatures SOI CMOS sensors, it can be employed in a variety of applications which require the use of CNTs or other nanomaterials with CMOS electronics. In our experiments we have grown CNTs both on SOI CMOS substrates and SOI CMOS microhotplates (suspended on membranes formed by post-CMOS deep RIE etching). The fully processed SOI substrates contain CMOS devices and circuits and additionally, some wafers contained high current LDMOSFETs and bipolar structures such as Lateral Insulated Gate Bipolar Transistors. All these devices were used as test structures to investigate the effect of additional post-CMOS processing such as CNT growth, membrane formation, high temperature annealing, etc. Electrical characterisation of the devices with CNTs were performed along with SEM and Raman spectroscopy. The CNTs were grown both at low and high temperatures, the former being compatible with Aluminium metallization while the latter being possible through the use of the high temperature CMOS metallization (Tungsten). In both cases we have found that there is no change in the electrical behaviour of the CMOS devices, circuits or the high current devices. A slight degradation of the thermal performance of the CMOS microhotplates was observed due to the extra heat dissipation path created by the CNT layers, but this is expected as CNTs exhibit a high thermal conductance. In addition we also observed that in the case of high temperature CNT growth a slight degradation in the manufacturing yield was observed. This is especially the case where large area membranes with a diameter in excess of 500 microns are used.

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集约化养殖大量使用铜(Cu)作为饲料添加剂会在养殖废物的排放和利用中导致一定的环境问题。随着东北老工业基地产业结构的调整,畜牧业作为东北地区二次振兴的主要产业得到迅速发展,由此会产生大量的畜禽粪便用于农业土壤施肥。而东北地区又是我国重要的农副产品生产基地,研究畜禽粪便农用的健康及环境风险就显得殊为必要。黑土是东北地区最主要的土壤类型,本文以东北黑土为供试材料,通过在盆栽实验中添加不同Cu浓度的猪粪来模拟施肥年限不同的菜园土,研究土壤中Cu累积对小白菜(Brassica chinensis L.)地上部分生物量与Cu含量、土壤微生物生物量和土壤酶(脱氢酶、脲酶、酸性磷酸酶)活性、微生物群落功能多样性以及对土壤功能微生物——氨氧化古菌(AOA)和氨氧化细菌(AOB)等的影响,从而实现含Cu猪粪农用对食物链途径的健康风险以及土壤生态系统的生态风险的综合评价。 研究结果表明,施用猪粪显著地改善了土壤的pH,增加了小白菜地上部分生物量,对其体内Cu浓度则没有显著影响;小白菜地上部分Cu浓度与土壤全Cu和水溶态Cu浓度显著正相关(P<0.01),而地上生物量与土壤全Cu浓度显著负相关(P<0.05)。当土壤全Cu浓度达到300 mg kg-1后,小白菜地上部分生物量受到强烈抑制。 猪粪的施用在一定时期内显著地促进了脱氢酶和脲酶的活性,但随土壤Cu浓度的增加,脱氢酶、脲酶和酸性磷酸酶的活性逐渐受到抑制。当土壤全Cu浓度达到300 mg kg-1后,微生物生物量、脱氢酶、脲酶、酸性磷酸酶等均受到强烈抑制。 施加猪粪提高了土壤微生物群落功能多样性,当土壤Cu浓度达到170 mg kg-1后,显著地抑制了微生物群落功能多样性。种植小白菜后,各处理间微生物群落功能多样性没有显著差异,意味着植物能够维持微生物群落功能多样性。主成分分析(PCA)结果显示,当土壤全Cu浓度达到300 mg kg-1后,微生物群落功能多样性与其它处理显著不同。 猪粪显著地促进了土壤的硝化潜势速率(PNR)。随着Cu浓度的增加,硝化潜势速率逐渐受到抑制,当土壤全Cu浓度达到170 mg kg-1后,即与对照无显著差异。植物在维持硝化速率方面也起到重要作用。古菌amoA基因在每克干土中的拷贝数在9.4*106~2.59*107,细菌amoA基因在每克干土中的拷贝数约为1.48*106~1.41*107。猪粪在一定时期内显著地增加了AOA和AOB的数量,当土壤Cu浓度达到300 mg kg-1后,AOA和AOB的数量显著下降,并且AOA与AOB amoA基因拷贝数的比值增加,在小白菜栽种前(B1)和小白菜收获后(B2)分别为2.33和9.26,这意味着在高Cu浓度胁迫下,AOA的耐受性更强。古菌与细菌的amoA拷贝数与PNR之间则没有显著的相关关系,意味着AOA和AOB种群结构以及其中某些种群的活性可能发生了变化。 本文通过对东北黑土菜地土壤中Cu在作物体内的迁移积累及其对土壤微生物学指标(微生物生物量、酶活性、微生物群落功能多样性及功能微生物)的影响的综合研究,揭示了含Cu猪粪农用所造成的健康和生态风险,为建立适宜的土壤环境质量标准提供了一定的科学依据。通过本研究得出,黑土蔬菜种植中Cu浓度的阈值在170-300 mg kg-1之间。

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To control combustion instabilities occurring in LPP gas turbine combustors, several active and passive systems have been developed in recent years. The combustion chamber cooling geometry has the potential to influence instability feedback loops by absorbing acoustical energy inside the combustor. The design of the cooling liner and the geometry of the cooling plenum and the cooling air flow rate have a significant influence on the absorption characteristics of the system. This paper presents the results of a cold flow study which was carried out in the course of a comprehensive study on the influence of the cooling geometry on combustor thermoacoustics. Absorption characteristics of three different cooling liner geometries and non-perforated plates were determined over a frequency range from 50 Hz to 600 Hz for different cooling flow rates and different cooling plenum volumes. The experimental results compared well with results from a low order thermoacoustic network model. The acoustic energy absorption spectrum of a cooling liner with 90°-hole configuration was found to be strongly dependent on cooling flow rate and cooling plenum volume, whereas the absorption spectrum of cooling liners with 25°-holes were found to be strongly dependent on the cooling plenum volume, but less dependent on the cooling air flow rate. All cooling liner setups with perforations were capable of increased acoustic absorption over a broad band of frequencies compared to the case of non-perforated combustor walls. © 2010 by Johannes Schmidt.

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用技术扩增中华鲜, , 线粒体控制区一时, 发现中华鳃天然群体内存在个体间和个体内的长度变异现象。测序表明, 长度 变异发生在仆靠近月刀的位置, 由长约碱基对的重复序列串联形成 的。由个体内长度变异造成的异质性个体比例为, 非异质性同质性个体的比 例为。非异质性个体间的的大小也不一样, 存在长度变异。在非异质性个体 中, 有、、、个串联重复序列形成的种分子类型的情况, 其重复序列出现的频率从高到低 的循序是一一一。在异质性个体中, 同一个体由种不同分子组合的异质体最普通, 占 。种不同分子组合的频率次之, 占。种不同分子组合的异质体比例最少, 占 。没有发现由种不同分子组合的异质体。对所有异质体混合分析表明, 各种类型的重 复序列出现的比例与非异质体的类似, 即分子大小含重复序列数从高到低的顺序为一 一一一。对尾中华鲜的个体内和个体间的遗传多样性指数分析发现, 有遗传变异 表现在群体内的个体间, 有的遗传变异表现在个体内。由长度异质性造成的个 体内的多样性是中华鲜物种遗传多样性的另一途径。