985 resultados para Jefferson Canyon
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Hoover Pugedo light traps were modified for use with green and blue-light-emitting diodes to trap phlebotomine sandflies in northeastern Brazil. A total of 2,267 specimens belonging to eight genera and 15 species were sampled. The predominant species were Nyssomyia whitmani(34.41%) and Micropygomyia echinatopharynx(17.25%).The green LED trap prevailed over the blue and control lights; however, no statistically significant difference could be detected among the three light sources. Even without statistical significance, we suggest using LEDs as an attractant for the capture of sandflies because of several advantages over the conventional method with incandescent lamps.
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Sulfur speciation and the sources of water-soluble sulfate in three oxidizing sulfidic mine tailings impoundments were investigated by selective dissolution and stable isotopes. The studied tailings impoundments-Piuquenes, Cauquenes, and Salvador No. 1-formed from the exploitation of the Rio Blanco/La Andina, El Teniente, and El Salvador Chilean porphyry copper deposits, which are located in Alpine, Mediterranean, and hyperarid climates, respectively. The water-soluble sulfate may originate from dissolution of primary ore sulfates (e.g., gypsum, anhydrite, jarosite) or from oxidation of sulfide minerals exposed to aerobic conditions during mining activity. With increasing aridity and decreasing pyrite content of the tailings, the sulfur speciation in the unsaturated oxidation zones showed a trend from dominantly Fe(Ill) oxyhydroxide fixed sulfate (e.g., jarosite and schwertmannite) in Piuquenes toward increasing presence of water-soluble sulfate at Cauquenes and Salvador No. 1. In the saturated primary zones, sulfate is predominantly present in water-soluble form (mainly as anhydrite and/or gypsum). In the unsaturated zone at Piuquenes and Cauquenes,the delta(34)S(S04) values ranged from +0.5 parts per thousand to +2.0 parts per thousand and from -0.4 parts per thousand to +1.4 parts per thousand Vienna Canyon Diablo Troilite (V-CDT), respectively, indicating a major sulfate source from pyrite oxidation (delta(34)S(pyrite) -1.1 parts per thousand and -0.9 parts per thousand). In the saturated zone at Piuquenes and Cauquenes, the values ranged from -0.8%. to +0.3 parts per thousand and from +2.2 parts per thousand to +3.9 parts per thousand, respectively. At Cauquenes the 34 S enrichment in the saturated zone toward depth indicates the increasing contribution of isotopically heavy dissolved sulfate from primary anhydrite (similar to+10.9%o). At El Salvador No. 1, the delta(34)S(SO4) average value is -0.9 parts per thousand, suggesting dissolution of supergene sulfate minerals (jarosite, alunite, gypsum) with a delta(34)S similar to -0.7 parts per thousand as the most probable sulfate source. The gradual decrease Of delta(18)O(S04) values from the surface to the oxidation front in the tailings impoundments at Piuquenes (from -4.5 parts per thousand to -8.6 parts per thousand Vienna Standard Mean Ocean Water, V-SMOW) and at Cauquenes (from -1.3 parts per thousand to -3.5 parts per thousand) indicates the increasing importance of ferric iron as the main electron acceptor in the oxidation of pyrite. The different delta(18)O(SO4) values between the tailings impoundments studied here reflect the local climates.
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Au travers d'une étude parallèle de deux femmes esclaves - l'une figure historique, l'autre personnage de fiction - et de la façon dont elles ont été inscrites dans, et surtout hors du récit historique et littéraire américain, cet essai vise d'une part à interroger les biais et les limitations de l'historiographie traditionnelle américaine dans sa représentation de l'esclave, et d'autre part à évaluer le rôle de la littérature dans la critique et la « re-vision » du discours historique. Le roman de Gloria Naylor Mama Day (1988) offre ainsi un détour intéressant pour mettre en lumière les processus discursifs, épistémologiques et idéologiques qui ont permis et perpétué l'absence de femmes comme Sally Hemings, esclave et maîtresse supposée de Thomas Jefferson, dans l'Histoire américaine.Through a parallel discussion of two slave women - the first a historical figure, the second a fiction character - and of the way they have been inscribed in, and indeed out of, the historical and fictional narrative of America's past, this essay aims both to interrogate the biases and limitations of traditional American historiography in its representation of slaves and to evaluate the role of literature in the critique and "re-vision" of historical discourse. Gloria Naylor's novel Mama Day (1988) thus provides an interesting detour to cast light on the discursive, epistemological and ideological processes that have permitted and perpetuated the absence from American History of women like Sally Hemings, Thomas Jefferson's slave and supposed mistress.
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The overarching goal of the proposed research was to evaluate the hydraulic performance of twenty two (22) fish-passage structures located in close proximity to bridges in western Iowa and within the HCA (Hungry Canyon Alliance) territory. Such structures include riprap weirs, fish ladders and grouted ripraps. The hydraulic performance of the aforementioned structures was evaluated via detailed field tests for a range of flow conditions relevant to fish migration through bridge waterways in different streams in western Iowa.
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This cross-sectional study aimed to analyze the adherence to drug and non-drug treatments in 17 Family Health Strategy units. A total of 423 patients with type 2 diabetes mellitus were selected through stratified random sampling in Family Health Strategy units of a city in the state of Minas Gerais, Brazil, in 2010. The results showed that the prevalence rate of adherence to drug therapy was higher than 60% in the 17 units investigated; in relation to physical activity, adherence was higher than 60% in 58.8% units; and for the diet plan, there was no adherence in 52.9% units. Therefore, we concluded that adherence to drug therapy in most units was high and the practice of physical activity was heterogeneous, and in relation to diet adherence, it was low in all units. We recommend strengthening of institutional guidelines and educational strategies, in line with SUS guidelines, so that, professionals may face the challenges imposed by the lack of adherence.
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A erosão hídrica é a forma mais séria de degradação do solo, pois, além de reduzir a capacidade produtiva deste para as culturas, causa prejuízos financeiros e ambientais em razão da perda de nutrientes a ela associada. A presente pesquisa foi realizada com o objetivo de quantificar as perdas de água e solo, de P, K, Ca e Mg na água e de P disponível e K, Ca e Mg trocáveis nos sedimentos da enxurrada perdida por erosão hídrica, em um experimento realizado sob chuva natural, entre novembro de 1992 e outubro de 2003, no sul do Planalto Catarinense. Calculou-se o custo financeiro desses nutrientes, expressos na forma de superfosfato triplo (P), cloreto de potássio (K) e de calcário (Ca e Mg), perdidos na erosão hídrica, para um Cambissolo Húmico alumínico léptico com declividade média de 0,10 m m-1, em três sistemas de manejo do solo, com duas repetições: preparo convencional (PC), preparo mínimo (PM) e semeadura direta (SD). Em uma das repetições dos tratamentos foram cultivados soja, trigo, milho, ervilhaca, feijão, aveia, soja e nabo forrageiro, em sistema de rotação de culturas, enquanto na outra se cultivaram soja, trigo, soja, trigo, soja, trigo, soja e trigo, em sistema de sucessão de culturas. Para efeito de realização deste trabalho, as duas parcelas experimentais com o mesmo tipo de manejo do solo foram consideradas como repetição, embora com diferentes espécies culturais (em rotação e em sucessão de culturas). As perdas de solo foram fortemente influenciadas pelo sistema de manejo e variaram com os anos de cultivo, enquanto as perdas de água variaram menos do que as de solo, tanto nos sistemas de manejo do solo quanto nos anos de cultivo. O valor monetário das perdas anuais de P expresso na forma de superfosfato triplo, de K expresso como cloreto de potássio e de Ca e Mg expressos na forma de calcário, por erosão hídrica, foi relativamente elevado, independentemente do sistema de manejo do solo. A SD e o PM comportaram-se de modo semelhante em termos de valor monetário das referidas perdas, em cujos tratamentos as perdas de água e solo foram expressivamente menores que no preparo convencional. O valor monetário da perda anual por hectare de K expresso na forma de cloreto de potássio, por erosão hídrica, foi equivalente a 2,6 vezes aquele representado pelo somatório das perdas de P na forma de superfosfato triplo e de Ca e Mg na forma de calcário, na média dos sistemas de manejo do solo. Na SD, essas perdas foram de US$ 14,83 por hectare por ano, enquanto no PM foram de US$ 16,33 e, no PC, de US$ 24,94. Na média destes sistemas de manejo do solo, o valor monetário total anual por hectare das perdas de P expresso na forma de superfosfato triplo correspondeu a 8,6 %, enquanto de K na forma de cloreto de potássio e de Ca e Mg expressos na forma de calcário o valor correspondeu a 76,8 e 14,6 %, respectivamente.
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O objetivo deste trabalho foi quantificar o armazenamento, a disponibilidade e a extração de água no solo por plantas de milho irrigadas e submetidas a déficit hídrico terminal, cultivadas sob sistema de semeadura direta e preparo convencional. Foram realizados dois experimentos durante os anos agrícolas de 1999/00 e 2000/01, em área experimental do Departamento de Engenharia Rural da Universidade Federal de Santa Maria. Utilizou-se o delineamento experimental inteiramente casualizado, fatorial, com quatro repetições. Foram utilizados dois manejos da água de irrigação (fator A): irrigado e déficit hídrico terminal (plantas de milho foram submetidas a déficit hídrico terminal a partir dos 27 dias após a emergência); e dois sistemas de cultivo (fator B): semeadura direta e preparo convencional. Nas parcelas irrigadas, irrigações foram feitas para elevar o conteúdo de água no solo ao limite superior de disponibilidade de água às plantas, sempre que a evapotranspiração máxima acumulada da cultura do milho atingia 25 mm. O conteúdo de água no solo foi medido em três leituras semanais, para determinação da extração de água pelas plantas e disponibilidade de água às plantas de milho. Os resultados indicaram que a disponibilidade de água às plantas de milho foi similar nos sistemas semeadura direta e preparo convencional, em ambos os anos agrícolas avaliados. Plantas de milho cultivadas em preparo convencional extraíram maior quantidade de água, em ambos os anos, em relação à semeadura direta.
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Em solos de restinga de constituição areno-quartzosa aumenta a influência da fração orgânica e da atividade biológica em funções-chave dos solos, como a capacidade de reciclar e armazenar nutrientes. A análise de atributos do solo e da fauna edáfica em sítios sob diferentes coberturas vegetais é importante para entender o comportamento desses ambientes. Neste estudo, avaliaram-se atributos químicos, físicos e microbiológicos do solo e suas relações com a população de formigas de sítios de restinga sob diferentes coberturas vegetais no Estado de Sergipe. Foram coletadas amostras em seis coberturas vegetais (três sítios por cobertura), sendo quatro na área Caju (mata, capim-gengibre, coqueiral e capoeira) e duas na área Pirambu (mata de topo de duna e mata de sopé de duna). As análises químicas foram feitas em amostras coletadas nas camadas de 0-5 e 5-20 cm, e a atividade microbiana, avaliada por meio da hidrólise do diacetato de fluoresceína, foi determinada em amostras coletadas a 0-10 cm. A massa de fragmentos orgânicos foi avaliada em diferentes profundidades. Na avaliação das comunidades de formigas foram consideradas aquelas com atividade na superfície do solo. Na comparação entre os sítios foi utilizada a análise de componentes principais. Os atributos de compartimentos orgânicos (C orgânico, C orgânico dissolvido e fragmentos orgânicos) foram muito sensíveis à modificação da cobertura vegetal nos sítios do Caju, isolando os sítios sob mata dos alterados e os sítios sob capim-gengibre daqueles sob capoeira e coqueiral. Atributos da solução do solo influenciáveis pelo spray marinho (condutividade elétrica e concentração de K, Na e Mg) isolaram os sítios de Pirambu dos sítios do Caju. Os grupos de formiga mostraram elevado nível de especialização. A análise de correspondência canônica apontou baixa percentagem da variância da distribuição desses grupos e isolou os sítios de mata dos outros usos, indicando que existem outros atributos a serem considerados na distribuição.
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Settling particles were collected using sediment traps deployed along three transects in the Lacaze-Duthiers and Cap de Creus canyons and the adjacent southern open slope from October 2005 to October 2006. The settling material was analyzed to obtain total mass fluxes and main constituent contents (organic matter, opal, calcium carbonate, and siliciclastics). Cascades of dense shelf water from the continental shelf edge to the lower continental slope occurred from January to March 2006. They were traced through strong negative near-bottom temperature anomalies and increased current speeds, and generated two intense pulses of mass fluxes in January and March 2006. This oceanographic phenomenon appeared as the major physical forcing of settling particles at almost all stations, and caused both high seasonal variability in mass fluxes and important qualitative changes in settling material. Fluxes during the dense shelf water cascading (DSWC) event ranged from 90.1 g m(-2) d(-1) at the middle Cap de Creus canyon (1000 m) to 3.2 g m(-2) d(-1) at the canyon mouth (1900 m). Fractions of organic matter, opal and calcium carbonate components increased seaward, thus diminishing the siliciclastic fraction. Temporal variability of the major components was larger in the canyon mouth and open slope sites, due to the mixed impact of dense shelf water cascading processes and the pelagic biological production. Results indicate that the cascading event remobilized and homogenized large amounts of material down canyon and southwardly along the continental slope contributing to a better understanding of the off-shelf particle transport and the internal dynamics of DSWC events.
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The decomposition of plant residues is a biological process mediated by soil fauna, but few studies have been done evaluating its dynamics in time during the process of disappearance of straw. This study was carried out in Chapecó, in southern Brazil, with the objective of monitoring modifications in soil fauna populations and the C content in the soil microbial biomass (C SMB) during the decomposition of winter cover crop residues in a no-till system. The following treatments were tested: 1) Black oat straw (Avena strigosa Schreb.); 2) Rye straw (Secale cereale L.); 3) Common vetch straw (Vicia sativa L.). The cover crops were grown until full flowering and then cut mechanically with a rolling stalk chopper. The soil fauna and C content in soil microbial biomass (C SMB) were assessed during the period of straw decomposition, from October 2006 to February 2007. To evaluate C SMB by the irradiation-extraction method, soil samples from the 0-10 cm layer were used, collected on eight dates, from before until 100 days after residue chopping. The soil fauna was collected with pitfall traps on seven dates up to 85 days after residue chopping. The phytomass decomposition of common vetch was faster than of black oat and rye residues. The C SMB decreased during the process of straw decomposition, fastest in the treatment with common vetch. In the common vetch treatment, the diversity of the soil fauna was reduced at the end of the decomposition process.
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Accurately calibrated effective field theories are used to compute atomic parity nonconserving (APNC) observables. Although accurately calibrated, these effective field theories predict a large spread in the neutron skin of heavy nuclei. Whereas the neutron skin is strongly correlated to numerous physical observables, in this contribution we focus on its impact on new physics through APNC observables. The addition of an isoscalar-isovector coupling constant to the effective Lagrangian generates a wide range of values for the neutron skin of heavy nuclei without compromising the success of the model in reproducing well-constrained nuclear observables. Earlier studies have suggested that the use of isotopic ratios of APNC observables may eliminate their sensitivity to atomic structure. This leaves nuclear structure uncertainties as the main impediment for identifying physics beyond the standard model. We establish that uncertainties in the neutron skin of heavy nuclei are at present too large to measure isotopic ratios to better than the 0.1% accuracy required to test the standard model. However, we argue that such uncertainties will be significantly reduced by the upcoming measurement of the neutron radius in 208^Pb at the Jefferson Laboratory.
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Coats plus is a highly pleiotropic disorder particularly affecting the eye, brain, bone and gastrointestinal tract. Here, we show that Coats plus results from mutations in CTC1, encoding conserved telomere maintenance component 1, a member of the mammalian homolog of the yeast heterotrimeric CST telomeric capping complex. Consistent with the observation of shortened telomeres in an Arabidopsis CTC1 mutant and the phenotypic overlap of Coats plus with the telomeric maintenance disorders comprising dyskeratosis congenita, we observed shortened telomeres in three individuals with Coats plus and an increase in spontaneous γH2AX-positive cells in cell lines derived from two affected individuals. CTC1 is also a subunit of the α-accessory factor (AAF) complex, stimulating the activity of DNA polymerase-α primase, the only enzyme known to initiate DNA replication in eukaryotic cells. Thus, CTC1 may have a function in DNA metabolism that is necessary for but not specific to telomeric integrity.
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The TNF family ligand ectodysplasin A (EDA) and its receptor EDAR are required for proper development of skin appendages such as hair, teeth, and eccrine sweat glands. Loss of function mutations in the Eda gene cause X-linked hypohidrotic ectodermal dysplasia (XLHED), a condition that can be ameliorated in mice and dogs by timely administration of recombinant EDA. In this study, several agonist anti-EDAR monoclonal antibodies were generated that cross-react with the extracellular domains of human, dog, rat, mouse, and chicken EDAR. Their half-life in adult mice was about 11 days. They induced tail hair and sweat gland formation when administered to newborn EDA-deficient Tabby mice, with an EC(50) of 0.1 to 0.7 mg/kg. Divalency was necessary and sufficient for this therapeutic activity. Only some antibodies were also agonists in an in vitro surrogate activity assay based on the activation of the apoptotic Fas pathway. Activity in this assay correlated with small dissociation constants. When administered in utero in mice or at birth in dogs, agonist antibodies reverted several ectodermal dysplasia features, including tooth morphology. These antibodies are therefore predicted to efficiently trigger EDAR signaling in many vertebrate species and will be particularly suited for long term treatments.
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The recently measured inclusive electron-proton cross section in the nucleon resonance region, performed with the CLAS detector at the Thomas Jefferson Laboratory, has provided new data for the nucleon structure function F2 with previously unavailable precision. In this paper we propose a description of these experimental data based on a Regge-dual model for F2. The basic inputs in the model are nonlinear complex Regge trajectories producing both isobar resonances and a smooth background. The model is tested against the experimental data, and the Q2 dependence of the moments is calculated. The fitted model for the structure function (inclusive cross section) is a limiting case of the more general scattering amplitude equally applicable to deeply virtual Compton scattering. The connection between the two is discussed.