989 resultados para Single Measuremnet Mode
Resumo:
We report the first steps of a collaborative project between the University of Queensland, Polyflow, Michelin, SK Chemicals, and RMIT University; on simulation, validation and application of a recently introduced constitutive model designed to describe branched polymers. Whereas much progress has been made on predicting the complex flow behaviour of many - in particular linear - polymers, it sometimes appears difficult to predict simultaneously shear thinning and extensional strain hardening behaviour using traditional constitutive models. Recently a new viscoelastic model based on molecular topology, was proposed by McLeish and Larson (1998). We explore the predictive power of a differential multi-mode version of the pom-pom model for the flow behaviour of two commercial polymer melts: a (long-chain branched) low-density polyethylene (LDPE) and a (linear) high-density polyethylene (HDPE). The model responses are compared to elongational recovery experiments published by Langouche and Debbaut (1999), and start-up of simple shear flow, stress relaxation after simple and reverse step strain experiments carried out in our laboratory.
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This study examines batch-to-batch variability in the production of dietary fluids and videofluoroscopy fluids of a single hospital. The material properties, such as viscosity, yield stress, and density, show significant variations between batches. Also waterbased products (i.e., cordial) provide (a) the most stability from week to week for both dietary and videofluoroscopy fluids and (b) the best dietary and videofluoroscopy fluid matches. The study also highlights the need for further research into how base substances, such as water, juice, and dairy products, react with different thickeners and with barium.
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We introduce a conceptual model for the in-plane physics of an earthquake fault. The model employs cellular automaton techniques to simulate tectonic loading, earthquake rupture, and strain redistribution. The impact of a hypothetical crustal elastodynamic Green's function is approximated by a long-range strain redistribution law with a r(-p) dependance. We investigate the influence of the effective elastodynamic interaction range upon the dynamical behaviour of the model by conducting experiments with different values of the exponent (p). The results indicate that this model has two distinct, stable modes of behaviour. The first mode produces a characteristic earthquake distribution with moderate to large events preceeded by an interval of time in which the rate of energy release accelerates. A correlation function analysis reveals that accelerating sequences are associated with a systematic, global evolution of strain energy correlations within the system. The second stable mode produces Gutenberg-Richter statistics, with near-linear energy release and no significant global correlation evolution. A model with effectively short-range interactions preferentially displays Gutenberg-Richter behaviour. However, models with long-range interactions appear to switch between the characteristic and GR modes. As the range of elastodynamic interactions is increased, characteristic behaviour begins to dominate GR behaviour. These models demonstrate that evolution of strain energy correlations may occur within systems with a fixed elastodynamic interaction range. Supposing that similar mode-switching dynamical behaviour occurs within earthquake faults then intermediate-term forecasting of large earthquakes may be feasible for some earthquakes but not for others, in alignment with certain empirical seismological observations. Further numerical investigation of dynamical models of this type may lead to advances in earthquake forecasting research and theoretical seismology.
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Antibodies have the potential to be therapeutic reagents for malaria. Here we describe the production of a novel phage antibody display library against the C-terminal 19 kDa region of the Plasmodium yoelii YM merozoite surface protein-1 (MSP1(19)). In vivo studies against homologous lethal malaria challenge show an anti-parasite effect in a dose dependent manner, and analysis by plasmon resonance indicates binding to the antigen is comparable to the binding of a protective monoclonal antibody. The data support the lack of a need for any antibody Fc-related function and hold great significance for the development of a therapeutic reagent for malaria. (C) 2002 Elsevier Science Ltd. All rights reserved.
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It has been reported that there is a relationship between a single-nucleotide polymorphism (SNP) in the promoter region of the CD 14 gene at position -159 (C-->T) and infectious diseases. The aim of the present study was to test the hypthesis that expression of this SNP correlates with periodontal disease in a Japanese population. The CD14 genotype was determined in 163 subjects with periodontitis and in 104 age- and gender-matched control subjects without periodontitis. The genotype distribution and allele frequency within the periodontitis patients were not significantly different from those of control subjects. There was, however, a significant difference in the genotype distribution between young patients (< 35 yrs) and older patients (greater than or equal to 35 yrs). These findings suggest that CD14-159C/T polymorphism is not related to the development of periodontitis in a Japanese population, but that, within the periodontitis subjects, expression of the SNP may be related to early disease activity.
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The effect of heating and cooling on heart rate in the estuarine crocodile Crocodylus porosus was studied in response to different heat transfer mechanisms and heat loads. Three heating treatments were investigated. C. porosus were: (1) exposed to a radiant heat source under dry conditions; (2) heated via radiant energy while half-submerged in flowing water at 23degreesC and (3) heated via convective transfer by increasing water temperature from 23degreesC to 35degreesC. Cooling was achieved in all treatments by removing the heat source and with C. porosus half-submerged in flowing water at 23degreesC. In all treatments, the heart rate of C. porosus increased markedly in response to heating and decreased rapidly with the removal of the heat source. Heart rate during heating was significantly faster than during cooling at any given body temperature, i.e. there was a significant heart rate hysteresis. There were two identifiable responses to heating and cooling. During the initial stages of applying or removing the heat source, there was a dramatic increase or decrease in heart rate ('rapid response'), respectively, indicating a possible cardiac reflex. This rapid change in heart rate with only a small change or no change in body temperature (
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Intervalley interference between degenerate conduction band minima has been shown to lead to oscillations in the exchange energy between neighboring phosphorus donor electron states in silicon [B. Koiller, X. Hu, and S. Das Sarma, Phys. Rev. Lett. 88, 027903 (2002); Phys. Rev. B 66, 115201 (2002)]. These same effects lead to an extreme sensitivity of the exchange energy on the relative orientation of the donor atoms, an issue of crucial importance in the construction of silicon-based spin quantum computers. In this article we calculate the donor electron exchange coupling as a function of donor position incorporating the full Bloch structure of the Kohn-Luttinger electron wave functions. It is found that due to the rapidly oscillating nature of the terms they produce, the periodic part of the Bloch functions can be safely ignored in the Heitler-London integrals as was done by Koiller, Hu, and Das Sarma, significantly reducing the complexity of calculations. We address issues of fabrication and calculate the expected exchange coupling between neighboring donors that have been implanted into the silicon substrate using an 15 keV ion beam in the so-called top down fabrication scheme for a Kane solid-state quantum computer. In addition, we calculate the exchange coupling as a function of the voltage bias on control gates used to manipulate the electron wave functions and implement quantum logic operations in the Kane proposal, and find that these gate biases can be used to both increase and decrease the magnitude of the exchange coupling between neighboring donor electrons. The zero-bias results reconfirm those previously obtained by Koiller, Hu, and Das Sarma.
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Free-space optical interconnects (FSOIs), made up of dense arrays of vertical-cavity surface-emitting lasers, photodetectors and microlenses can be used for implementing high-speed and high-density communication links, and hence replace the inferior electrical interconnects. A major concern in the design of FSOIs is minimization of the optical channel cross talk arising from laser beam diffraction. In this article we introduce modifications to the mode expansion method of Tanaka et al. [IEEE Trans. Microwave Theory Tech. MTT-20, 749 (1972)] to make it an efficient tool for modelling and design of FSOIs in the presence of diffraction. We demonstrate that our modified mode expansion method has accuracy similar to the exact solution of the Huygens-Kirchhoff diffraction integral in cases of both weak and strong beam clipping, and that it is much more accurate than the existing approximations. The strength of the method is twofold: first, it is applicable in the region of pronounced diffraction (strong beam clipping) where all other approximations fail and, second, unlike the exact-solution method, it can be efficiently used for modelling diffraction on multiple apertures. These features make the mode expansion method useful for design and optimization of free-space architectures containing multiple optical elements inclusive of optical interconnects and optical clock distribution systems. (C) 2003 Optical Society of America.
Resumo:
Complete biological nutrient removal (BNR) in a single tank, sequencing batch reactor (SBR) process, is demonstrated here at full-scale on a typical domestic wastewater. The unique feature of the UniFed process is the introduction of the influent into the settled sludge blanket during the settling and decant periods of the SBR operation. This achieves suitable conditions for denitrification and anaerobic phosphate release which is critical to successful biological phosphorus removal, It also achieves a selector effect, which helps in generating a compact, well settling biomass in the reactor. The results of this demonstration show that it is possible to achieve well over 90% removal of GOD, nitrogen and phosphorus in such a process. Effluent quality achieved over a six-month operating period directly after commissioning was: 29 mg/l GOD, 0.5 mg/l NH4-N, 1.5 mg/l NOx-N and 1.5 mg/l PO4-P (50%-iles of daily samples). During an 8-day, intensive sampling period, the effluent BOD5 was
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Throughout the latter months of 2000 and early 2001, the Australian public, media and parliament were engaged in a long and emotive debate about motherhood. This debate constructed the two main protagonists, the unborn 'child' and the potential mother, with a variety of different and often oppositional identities. The article looks at the way that these subject identities interacted during the debate, starting from the premise that policy making has unintended and unacknowledged material outcomes, and using governmentality as a tool through which to analyse and understand processes of identity manipulation and resistance within policy making. The recent debate concerning the right of lesbian and single women to access new reproductive technologies in Australia is used as a case study. Nominally the debate was about access to IVF technology; in reality, however, the debate was about the governing of women and, in particular, the governing of motherhood identities. The article focuses on the parliamentary debate over the drafting of legislation designed to stop lesbian and single women from accessing these technologies, particularly the utilization of the 'unborn' subject within these debates as a device to discipline the identity of 'mother'.
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Low-temperature (15 K) single-crystal neutron-diffraction structures and Raman spectra of the salts (NX4)(2)[CU(OX2)(6)](SO4)(2), where X = H or D, are reported. This study is concerned with the origin of the structural phase change that is known to occur upon deuteration. Data for the deuterated salt were measured in the metastable state, achieved by application of 500 bar of hydrostatic pressure at similar to303 K followed by cooling to 281 K and the subsequent release of pressure. This allows for the direct comparison between the hydrogenous and deuterated salts, in the same modification, at ambient pressure and low temperature. The Raman spectra provide no intimation of any significant change in the intermolecular bonding. Furthermore, structural differences are few, the largest being for the long Cu-O bond, which is 2.2834(5) and 2.2802(4) Angstrom for the hydrogenous and the deuterated salts, respectively. Calorimetric data for the deuterated salt are also presented, providing an estimate of 0.17(2) kJ/mol for the enthalpy difference between the two structural forms at 295.8(5) K. The structural data suggest that substitution of hydrogen for deuterium gives rise to changes in the hydrogen-bonding interactions that result in a slightly reduced force field about the copper(II) center. The small structural differences suggest different relative stabilities for the hydrogenous and deuterated salts, which may be sufficient to stabilize the hydrogenous salt in the anomalous structural form.
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Problematiza a constituição do currículo (e da “formação docente” no campo curricular), no cotidiano escolar, na dimensão das conversações. Objetiva acompanhar os movimentos curriculares concernentes ao Proeja entre formas e forças complexas no cotidiano do Ifes – campus Venda Nova do Imigrante (VNI). Compõe com as linhas de pensamentos principalmente de Alves (2008, 2010, 2012); Carvalho (2004, 2008a, 2008b, 2009, 2012); Deleuze (1988, 2002, 2010); Deleuze e Guattari (1995); Ferraço (2007, 2008a, 2008b); Garcia (2011); Guattari (1987, 2004, 2012); Kastrup (2009, 2013); Lopes e Macedo (2011); Lopes (2010, 2011); Oliveira (2005, 2009, 2012); Paiva (2004, 2009); Rolnik (1989); e Spinoza (2013), entremeando os conceitos de movimentos e afetos no campo do currículo em redes na relação híbrida com os encontros-formações docente do/no Proeja. Adota a (não) metodologia cartográfica ao acompanhar movimentos curriculares (des)(re)territorializantes nas redes de conversações, especialmente nos encontrosformações: “Rodas de conversas com professores e demais servidores do Proeja”. Utiliza como principais instrumentos metodológicos a observação participante, a gravação das vozes e o registro em diário de campo. Contribui para outros movimentos de pesquisa ao capturar produzir e analisar dados em que se percebe que: ainda que tenha ocorrido um planejamento coletivo, outras temáticas surgiram nos encontros formações (que não se pretendiam engessados e não objetivavam a paralisação dos fluxos que pedem passagem), e tais assuntos puderam ser usados como disparadores para criação de outros movimentos curriculares; as concepções dos professores sobre a “dificuldade/facilidade” em ministrar aulas para o Proeja e os lugares estabelecidos entre estudantes e docentes no processo ensino-aprendizagem não estão relacionados diretamente, em relação de causa e efeito, à disciplina/área de conhecimento específica que ministram, mas aos agenciamentos, aos ligamentos e às rupturas produzidas nas relações com essas redes de saberes fazeres poderes que envolvem múltiplos agentes: docentes, outros servidores, alunos, experiências e encontros múltiplos dentro fora no espaço tempo do Ifes; uma tríade-refrão coopera para a criação de uma fôrma triangular que enfatiza a noção de um padrão em um processo molar enraizado nas árvores do conhecimento: perfil, seleção e nivelamento, contudo, algumas linhas de fuga dissonantes são criadas por entre as fissuras dos pretensos tons harmônicos; as frases “os professores do IF não estão preparados para ministrar aulas para o Proeja” ou “não há formação/qualificação para os docentes se relacionarem com o Proeja” são utilizadas, em alguns discursos, como escudos-argumentos para a opção-política de não oferta de vagas para a modalidade EJA em composição com fios que afirmam tal especificidade da educação básica, dentro da rede federal, como um “favor social”; processos que envolvem a (des)organização da matriz curricular são considerados por alguns participantes como início, “produto” e objetivo das conversas curriculares e provocam tensões que (i)mobilizam, (não) movimentam entre os afetos dos corpos, podendo levar à (não) ação coletiva; a noção de “mercado de trabalho” ainda impera nos discursos, ciclicamente, enquanto início fim das problematizações do currículo do Ensino Médio e da EJA; a expressão “integração curricular” é constantemente usada nos discursos que circulam o campus, no entanto, os sentidos produzidos, as concepções e as teorias curriculares que embasam a noção de “integração” no currículo são bem diversos; não há totalidades nos discursos, não há homogeneização, não foi efetivada nenhuma coesão/única voz representante (e esse também não era o objetivo desta pesquisa); ainda que o tema da roda se propusesse às conversas curriculares do/no Proeja, nesses encontros, os participantes manifestaram a necessidade de intensificar os movimentos produzidos nas rodas visando à discussão dos currículos textos de todos os cursos e modalidades ofertados pelos campus VNI e na intensificação de espaços para trocas de experiências curriculares cotidianas; na potencialização das diferenças como possibilidades de inventividade nos encontros-formações docente e nas danças curriculares que envolvem diversas relações de aprendizagem no Ifes, algumas experimentações foram produzidas, entre afetos, criando composições(des)(re)territorializantes e ressonando com movimentos que não se restringiram às rodas de conversas, contudo, enredaram-se em fios de outros espaços tempos do campus em tentativas de propagações de currículos multidão.
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It is shown that electrospun poly(vynilidene fluoride) nanofibers are fully poled right after preparation and show b-phase contents of 70%, therefore being able to be implemented into electroactive devices without further processing steps. Further,the local piezoelectric properties of individual electrospun fibers have been studied by piezoresponse force microscopy. Piezoelectric response, polarization switching, and nanoscale patterning of the fibers have been demonstrated.
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The use of cover crops is important for the agricultural crop and soil management in order to improve the system and, consequently, to increase yield. Therefore, the present study analyzed the effect of crop residues of black oat (Avena strigosa Schreb.) (BO) and a cocktail (CO) of BO, forage turnip (Raphanus sativus L.) (FT) and common vetch (Vicia sativa L.) (V) on the emergence speed index (ESI), seedling emergence speed (SES) plant height and soybean yield in different intervals between cover crop desiccation with glyphosate 480 (3 L ha-1) and BRS 232 cultivar sowing. Plots of 5 x 2.5 m with 1 m of border received four treatments with BO cover crops and four with CO as well as a control for each cover crop, at random, with five replications. The plots were desiccated in intervals of 1, 10, 20 and 30 days before soybean seeding. The harvest was manual while yield was adjusted to 13% of moisture content. The experimental design was completely randomized with splitplots and means compared by the Scott and Knott test at 5% of significance. The results showed that CO of cover crops can be recommended for soybean to obtain a more vigorous seedling emergence, from 10 days after cover crop desiccation.
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NBPT (N-(n-butyl) thiophosphoric triamide), a urease inhibitor, has been reported as one of the most promising compounds to maximize urea nitrogen use in agricultural systems. The objective of this study was to evaluate the performance of irrigated wheat fertilized with urea or urea + NBPT as single or split application. The experiment was conducted from June to October 2006 in Viçosa, MG, Brazil. The experimental design followed a 2×2 factorial scheme, in which urea or urea + NBPT were combined with two modes of application: full dose at sowing (60kg ha-1) or split (20kg ha-1 at sowing + 40kg ha-1 as topdressing at tillering), in randomized blocks with ten replications. The split application of nitrogen fertilization does not improve the yield wheat under used conditions. The use of urease inhibitor improves the grain yield of wheat crop when urea is applied in topdressing at tillering, but its use does not promote difference when urea is applied in the furrow at planting.