977 resultados para Hall, S. C. (Samuel Carter), 1800-1889.


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The chloroplast genes of dinoflagellates are distributed among small, circular dsDNA molecules termed minicircles. In this paper, we describe the structure of the non-coding region of the psbA minicircle from Symbiodinium. DNA sequence was obtained from five Symbiodinium strains obtained from four different coral host species (Goniopora tenuidens, Heliofungia actiniformis, Leptastrea purpurea and Pocillopora damicornis), which had previously been determined to be closely related using LSU rDNA region D1/D2 sequence analysis. Eight distinct sequence blocks, consisting of four conserved cores interspersed with two metastable regions and flanked by two variable regions, occurred at similar positions in all strains. Inverted repeats (IRs) occurred in tandem or 'twin' formation within two of the four cores. The metastable regions also consisted of twin IRs and had modular behaviour, being either fully present or completely absent in the different strains. These twin IRs are similar in sequence to double-hairpin elements (DHEs) found in the mitochondrial genomes of some fungi, and may be mobile elements or may serve a functional role in recombination or replication. Within the central unit (consisting of the cores plus the metastable regions), all IRs contained perfect sequence inverses, implying they are highly evolved. IRs were also present outside the central unit but these were imperfect and possessed by individual strains only. A central adenine-rich sequence most closely resembled one in the centre of the non-coding part of Amphidinium operculatum minicircles, and is a potential origin of replication. Sequence polymorphism was extremely high in the variable regions, suggesting that these regions may be useful for distinguishing strains that cannot be differentiated using molecular markers currently available for Symbiodinium.

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The flow stress in tension and compression has been measured as a function of plastic strain in Mg-2Zn castings with grain sizes ranging from 55 to 340 mum. Hall-Petch parameters have been calculated and are compared to those previously reported. In contrast to the behaviour of pure Mg grain refined with Zr and of hot-worked and recrystallised pure Mg and Mg-Zn alloys, the cast material shows little tension/compression asymmetry of the flow stress. The possible effects of texture and of twinning are noted. (C) 2004 Elsevier B.V. All rights reserved.

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We show that the one-way channel formalism of quantum optics has a physical realization in electronic systems. In particular, we show that magnetic edge states form unidirectional quantum channels capable of coherently transporting electronic quantum information. Using the equivalence between one-way photonic channels and magnetic edge states, we adapt a proposal for quantum state transfer to mesoscopic systems using edge states as a quantum channel, and show that it is feasible with reasonable experimental parameters. We discuss how this protocol may be used to transfer information encoded in number, charge, or spin states of quantum dots, so it may prove useful for transferring quantum information between parts of a solid-state quantum computer

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This prospective study evaluated serum procalcitonin (PCT) and C-reactive protein (CRP) as markers for systemic inflammatory response syndrome (SIRS)/sepsis and mortality in patients with traumatic brain injury and subarachnoid haemorrhage. Sixty-two patients were followed for 7 days. Serum PCT and CRP were measured on days 0, 1, 4, 5, 6 and 7. Seventy-seven per cent of patients with traumatic brain injury and 83% with subarachnoid haemorrhage developed SIRS or sepsis (P= 0.75). Baseline PCT and CRP were elevated in 35% and 55% ofpatients respectively (P=0.03). There was a statistically non-significant step-wise increase in serum PCT levels from no SIRS (0.4 +/- 0.6 ng/ml) to SIRS (3.05 +/- 9.3 ng/ml) to sepsis (5.5 +/- 12.5 ng/ml). A similar trend was noted in baseline PCT in patients with mild (0.06 +/- 0.9 ng/ml), moderate (0.8 +/- 0.7 ng/ml) and severe head injury (1.2 +/- 1.9 ng/ml). Such a gradation was not observed with serum CRP There was a non-significant trend towards baseline PCT being a better marker of hospital mortality compared with baseline CRP (ROC-AUC 0.56 vs 0.31 respectively). This is the first prospective study to document the high incidence of SIRS in neurosurgical patients. In our study, serum PCT appeared to correlate with severity of traumatic brain injury and mortality. However, it could not reliably distinguish between SIRS and sepsis in this cohort. This is in pan because baseline PCT elevation seemed to correlate with severity of injury. Only a small proportion ofpatients developed sepsis, thus necessitating a larger sample size to demonstrate the diagnostic usefulness of serum PCT as a marker of sepsis. Further clinical trials with larger sample sizes are required to confirm any potential role of PCT as a sepsis and outcome indicator in patients with head injuries or subarachnoid haemorrhage.

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In China, protected areas are one of the main destinations attracting tourists and homeland for many poor people living in and around them. Based on a case study, the paper focuses on correlation between tourism and poverty alleviation by tracing the cash flows to the local poor. It also reviews the social and environmental effects of tourism on local area. The case study is conducted in a group of protected areas in Qinling Mountain Region in Shaanxi, a western province in China. Qinling Mountain is one of the most important distribution zones for Giant Panda and some other endangered wildlife such as Golden Takin and Golden Monkey. The tourism development in the region is happening. Research indicates that there is 29.33%, of tourist expenditure is going to local households, directly or indirectly. Tourist spends US$7.11 (13.67%) in food and beverage, and US$6.39 (12.23%) in accommodation service, which are the greatest contributors to local households in terms of tourism benefits. Local households can get US$8.15 from food/beverage and accommodation sectors, taking 56.64% of total income from tourism. Generally, tourism development benefits all stakeholders. However, poor people get less benefit. The paper analyses the barriers for the poor to be involved in tourism development, and discusses the government roles, major issues in implementation of Sustainable Tourism-Eliminating Poverty (ST-EP) model.

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Esta pesquisa procura examinar, à luz da metodologia exegética, a perícope de Miqueias 2,1-5, a fim de reconstruir o cenário no qual emergiu a dura crítica social do profeta. O texto apresenta, em sua análise literária, características de um dito profético coeso, em estilo poético. Sua estrutura encontra-se dividida em duas unidades (denúncia e castigo), sendo que cada uma das unidades possui outras duas subunidades (genérica e especfica). O gênero literário harmoniza-se com um dito profético de julgamento geralmente conhecido como oráculo ai . A análise da dimenso histórica situa o acontecimento fundante em 701 a.C., na Sefelá judaíta. Numa análise investigativa do conteúdo da denúncia norteado pelo modelo teórico do modo de produção tributário, observa-se um conflito entre dois grupos. Nesse conflito, Miqueias faz uma acusação a um grupo de poder em Judá que planeja e executa ações criminosas contra a herança camponesa. O castigo descreve a conspiração e o plano divino contra esse grupo de poder. Javé havia planejado um mal idêntico ao que eles haviam cometido, desonra e privação de suas possessões. Os valores culturais de honra e vergonha subjazem a esse oráculo. Por descumprirem seus deveres junto a Javé e ao povo, os criminosos perderiam todos os seus direitos e, sobretudo, a honra perante a própria comunidade. Com base no modelo teórico do modo de produção tributário, constata-se que, na situação social em Judá no oitavo sculo, prevalecia um conflito entre campo e cidade. As comunidades aldeãs pagavam tributo à cidade em forma de produtos e serviços. A excessiva arrecadação de tributo e as falhas no sistema de ajuda mútua forçaram os indivíduos e famílias a contrair dívidas, a hipotecar suas terras herdadas dos pais e eventualmente perdê-las. O profeta Miqueias é o porta-voz do protesto da classe campesina que resolve reagir aos desmandos praticados pela elite citadina. Para ele, Javé escuta a queixa dos que estão sendo oprimidos e intervém na história tomando o partido do oprimido.(AU)

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The Genius of Erasmus Darwin provides insight into the full extent of Erasmus Darwin's exceptional intellect. He is shown to be a major creative thinker and innovator, one of the minds behind the late eighteenth-century industrial revolution, and one of the first, if not the first, to perceive the living world (including humans) as part of a unified evolutionary scenario. The contributions here provide contextual understandings of Erasmus Darwin's thought, as well as studies of particular works and accounts of the later reception of his writings. In this way it is possible to see why the young Samuel Taylor Coleridge was moved to describe Darwin as 'the first literary character in Europe, and the most original-minded man'. Erasmus Darwin, Charles Darwin's grandfather, was one of the leading intellectuals of eighteenth-century England. He was a man with an extraordinary range of interests and activities: he was a doctor, biologist, inventor, poet, linguist, and botanist. He was also a founding member of the Lunar Society, an intellectual community that included such eminent men as James Watt and Josiah Wedgwood. Contents: Introduction; Setting the scene, Jonathan Powers; Prologue 'Catching up with Erasmus Darwin in the New Century', Desmond King-Hele. Section 1: Medicine: Physicians and physic in 17th and 18th century Lichfield, Dennis Gibbs; Dr Erasmus Darwin MD FRS (1731–1802): England's greatest physician?, Gordon Cook; William Pale (1743–1805) and James Parkinson (1755–1824): two peri-Erasmatic thinkers (and several others), Christopher Gardner-Thorpe; The vertiginous philosophers: Erasmus Darwin and William Charles Wells on vertigo, Nicholas Wade. Section 2: Biology: The Antipodes and Erasmus Darwin: the place of Erasmus Darwin in the heritage of Australian literature and biology, John Pearn; Erasmus Darwin on human reproductive generation: placing heredity within historical and Zoonomian contexts, Philip Wilson; All from fibres: Erasmus Darwin's evolutionary psychobiology, C.U.M. Smith; Two special doctors: Erasmus Darwin and Luigi Galvani, Rafaella Simili. Section 3: Education: But what about the women? The lunar society's attitude to women and science and to the education of girls, Jenny Uglow; The Derbyshire 'Darwinians': the persistence of Erasmus Darwin's influence on a British provincial literary and scientific community, c.1780–1850, Paul Elliot. Section 4: Technology: Designing better steering for carriages (and cars); with a glance at other inventions, Desmond King-Hele; Mama and papa: the ancestors of modern-day speech science, Philip Jackson; Negative and positive images: Erasmus Darwin, Tom Wedgwood and the origins of photography, Alan Barnes; Section 5: Environment: Erasmus Darwin's contributions to the geological sciences, Hugh Torrens; The air man, Desmond King-Hele; Erasmus Darwin, work and health, Tim Carter; Section 6: Literature: The progress of society: Darwin's early drafts for the temple of nature, Martin Priestman; The poet as pathologist: myth and medicine in Erasmus Darwin's epic poetry, Stuart Harris; 'Another and the same': nature and human beings in Erasmus Darwin's doctrines of love and imagination, Maurizio Valsania. Epilogue: 'One great slaughter-house the warring world': living in revolutionary times, David Knight; Coda: Midlands memorabilia, Nick Redman; Appendix: The Creation of the Erasmus Darwin Foundation and Erasmus Darwin House, Tony Barnard; Index.

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We have used a high-energy ball mill to prepare single-phased nanocrystalline Fe, Fe90Ni10, Fe85Al4Si11, Ni99Fe1 and Ni90Fe10 powders. We then increased their grain sizes by annealing. We found that a low-temperature anneal (T < 0.4 Tm) softens the elemental nanocrystalline Fe but hardens both the body-centered cubic iron- and face-centered cubic nickel-based solid solutions, leading in these alloys to an inverse Hall–Petch relationship. We explain this abnormal Hall–Petch effect in terms of solute segregation to the grain boundaries of the nanocrystalline alloys. Our analysis can also explain the inverse Hall–Petch relationship found in previous studies during the thermal anneal of ball-milled nanocrystalline Fe (containing ∼1.5 at.% impurities) and electrodeposited nanocrystalline Ni (containing ∼1.0 at.% impurities).

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Anthony Hall was named for Libby C. Anthony who was a matron of girls as well as assistant in domestic economy. She was the first Treasurer for the National League of Afro-American Women and a life long resident of Jefferson City, Missouri. This three story brick building was completed in 1940 and served as a dormitory for Freshman and sophomore young women. It was renovated in 2007. It is now a co-ed residence hall for upperclassmen.

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The present work aims to show a possible relationship between the use of the History of Mathematics and Information and Communication Technologies (TIC) in teaching Mathematics through activities that use geometric constructions of the “Geometry of the Compass” (1797) by Lorenzo Mascheroni (1750-1800). For this, it was performed a qualitative research characterized by an historical exploration of bibliographical character followed by an empirical intervention based on use of the History of Mathematics combined with TIC through Mathematical Investigation. Thus, studies were performed in papers dealing with the topic, as well as a survey to highlight problems and /or episodes of the history of mathematics that can be solved with the help of TIC, allowing the production of a notebook of activities addressing the resolution of historical problems in a computer environment. In this search, we came across the problems of geometry that are presented by Mascheroni stated previously in the work that we propose solutions and investigations using GeoGebra software. The research resulted in the elaboration of an educational product, a notebook of activities, which was structure to allow during its implementation, students can conduct historical and/or Mathematics research, therefore, we present the procedures for realization of each construction, followed at some moments by original solution of the work. At the same time, we encourage students to investigate/reflect its construction (GeoGebra), in addition to making comparisons with the solution Mascheroni. This notebook was applied to two classes of the course of Didactics of Mathematics I (MAT0367) Course in Mathematics UFRN in 2014. Knowing the existence of some unfavorable arguments regarding the use of history of mathematics, such as loss of time, it was found that this factor can be mitigated with the aid of computational resource, because we can make checks using only the dynamism of and software without repeating the construction. It is noteworthy that the minimized time does not mean loss of reflection or maturation of ideas, when we adopted the process of historical and/or Mathematics Investigation

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES

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El 5º Informe del IPCC (Panel Intergubernamental de Cambio Climático, 2014) señala que el turismo será una de las actividades económicas que mayores efectos negativos experimentará en las próximas cadas debido al calentamiento térmico del planeta. En España, el turismo es una fuente principal de ingresos y de creación de puestos de trabajo en su economía. De ahí que sea necesaria la puesta en marcha de medidas de adaptación a la nueva realidad climática que, en nuestro país, va a suponer cambios en el confort climático de los destinos e incremento de extremos atmosféricos. Frente a los planes de adaptación al cambio climático en la actividad turística, elaborados por los gobiernos estatal y regional, que apenas se han desarrollado en España, la escala local muestra interesantes ejemplos de acciones de adaptación al cambio climático, desarrolladas tanto por los municipios (energía, transporte, vivienda, planificación urbanística) como por la propia empresa turística (hoteles, campings, apartamentos). Medidas de ahorro de agua y luz, fomento del transporte público y de las energías limpias, creación de zonas verdes urbanas y adaptación a los extremos atmosféricos destacan como acciones de mitigación del cambio climático en los destinos turísticos principales de nuestro país.

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Con este trabajo nos proponemos estudiar las políticas agrarias del franquismo y particularmente la creación y actuación del Servicio de Extensión Agraria (1955) en el contexto de la difusión de la Teoría de la Modernización. Comenzaremos con una contextualización de las relaciones culturales entre España y los EE.UU. y su potencial proyección sobre el ámbito rural. A continuación, prestaremos atención a la impronta del modelo extensionista norteamericano en la organización y metodología del Servicio de Extensión Agraria. Sin perder de vista la importancia de la escala estatal para la implementación y adaptación de las distintas políticas agrarias, atenderemos al contexto político e ideológico internacional como elemento que permite ampliar la comprensión y estudio de dichas políticas. En ese sentido, propondremos finalmente una primera aproximación comparativa al estudio del SEA en relación con diferentes experiencias de extensionismo agrario en Latinoamérica.