bluuebunny/crossref_metadata_2025 huggingface dataset:
Atividade pozolânica dos resíduos do beneficiamento do caulim para uso em argamassas para alvenaria
Authors: Menezes Romualdo R. , Neves Gelmires A. , Souza Jozilene , Melo Weyne A. , Ferreira Heber S. , Ferreira Heber C.
Published: October 2009

A indústria do beneficiamento do caulim gera enorme quantidade de resíduos, descartados indiscriminadamente no meio ambiente; assim, este trabalho tem por objetivo analisar a viabilidade técnica e a atividade pozolânica dos resíduos do beneficiamento do caulim para a produção de argamassas. Os resíduos foram caracterizados através da determinação de sua distribuição granulométrica e composição química, difração de raios X e análise térmica diferencial e gravimétrica; em seguida, determinou-se o índice de atividade pozolânica dos resíduos de caulim com a cal e o cimento Portland. Argamassas de cimento:cal:areia foram preparadas e o resíduo, na condição natural e após queima a 600 °C por 2 h, substituiu parcialmente o cimento nas proporções de 5, 10, 15 e 20% em massa. Corpos-de-prova foram moldados e determinada sua resistência a compressão simples. Conclui-se, com base nos resultados, que os resíduos são constituídos de caulinita, mica e quartzo e que a utilização do resíduo calcinado aumenta a resistência das argamassas após 28 dias de cura em até 150%.
Avaliação do conforto térmico e desempenho de frangos de corte sob regime de criação diferenciado
Authors: Nazareno Aérica C. , Pandorfi Héliton , Almeida Gledson L. P. , Giongo Pedro R. , Pedrosa Elvira M. R. , Guiselini Cristiane
Published: October 2009

Esta pesquisa foi conduzida com o objetivo de avaliar três sistemas de criação para frangos de corte industrial, visando caracterizar o ambiente térmico e o desempenho animal. O experimento foi realizado no decorrer de 42 dias, desenvolvido em módulos de produção, divididos em 15 boxes com 10 aves por box, submetidas a três sistemas de criação: semi-confinado com 3 m² por ave de área de piquete (SC 3), semi-confinado com 6 m² por ave de área de piquete (SC 6) e confinamento total (CONF). O delineamento experimental foi inteiramente casualizado (DIC) em parcelas subdivididas e médias comparadas pelo teste Tukey (P < 0,05). As variáveis meteorológicas e os índices de conforto apontam o sistema de criação SC 3 como o que permitiu melhor condicionamento térmico natural às aves, apresentando valores médios da ordem de 25,4 °C, 69,9 kJ kg-1 e 75,7 para temperatura de bulbo seco (Tbs), entalpia (h) e índice de temperatura de globo e umidade (ITGU), respectivamente. Os parâmetros fisiológicos freqüência respiratória (mov min-1) e temperatura cloacal (°C) indicaram valores médios mais adequados nas aves submetidas ao sistema de criação SC 3. Os sistemas de criação promoveram alterações no desempenho das aves para consumo de ração (CR) e peso corporal (PC) nos sistemas SC 3 e CONF, comparativamente ao SC 6, que apresentou prejuízo no desempenho.
Instrumento de avaliação de fala para análise acústica (IAFAC) baseado em critérios linguísticos
Authors: Berti Larissa Cristina , Pagliuso Alessandra , Lacava Francine
Published: October 2009

OBJETIVO: Elaborar um instrumento de avaliação da fala de crianças, que contemple todos os fonemas consonantais do Português Brasileiro, para viabilizar o uso de uma metodologia instrumental. MÉTODOS: A escolha das palavras foi baseada em critérios linguísticos do Português Brasileiro (PB), previamente definidos, pesquisados no banco de dados fônico-lexicais - CETENFolha, relativos: à classe gramatical, ao número de sílabas, ao acento e ao padrão silábico a partir da ocorrência das palavras-tipo. RESULTADOS: Com base nos critérios linguísticos o instrumento foi composto por 96 palavras que contemplavam pelo menos três ocorrências de todos os fonemas consonantais do PB que acompanhavam as vogais /i,a,u/ na posição acentuada. Dentre as palavras do instrumento houve a prevalência de substantivos dissílabos paroxítonos. Quanto ao padrão silábico, 57 palavras iniciavam com padrão silábico simples e 39 palavras envolviam a produção de padrão silábico complexo. CONCLUSÃO: O presente trabalho não só forneceu critérios linguísticos para elaboração de instrumentos de avaliação de produção e/ou percepção de fala, como também disponibilizou um instrumento de avaliação de fala para uso de uma metodologia instrumental para o campo da Fonoaudiologia.
Eficácia do emprego do espelho de Glatzel na avaliação da permeabilidade nasal
Authors: Bassi Iara Barreto , Franco Letícia Paiva , Motta Andréa Rodrigues
Published: October 2009

OBJETIVO: Comparar a medida do escape aéreo nasal, realizada por meio espelho de Glatzel, entre crianças com e sem obstrução de via aérea superior, de acordo com o sexo e a faixa etária. MÉTODOS: Amostra composta por 43 crianças, com média de 6,9 anos, separadas em quatro grupos: com indicação cirúrgica para desobstrução de via aérea superior (grupo cirúrgico), alérgicos com manifestação de obstrução (grupo alérgico), alérgicos com obstrução e indicação de cirurgia (grupo alérgico e cirúrgico) e crianças sem obstrução (grupo controle). A medida do escape foi realizada por meio do Espelho Nasal Milimetrado de Altmann e os dados mensurados em cm² pelo software AutoCAD 2002. Os dados foram analisados por meio de estatística descritiva e por testes de hipótese com nível de significância de 5%. RESULTADOS: O grupo controle foi o que apresentou a maior média (6,53 cm²) na medida do escape aéreo nasal, enquanto o grupo alérgico e cirúrgico apresentou a menor (3,07 cm²). As médias dos grupos alérgico e cirúrgico foram de 4,74 cm² e 5,91 cm², respectivamente. Apenas o grupo alérgico e cirúrgico apresentou diferença significante em relação ao grupo controles. Verificou-se ainda que a medida de escape não foi estatisticamente afetada pelas variáveis sexo e idade. CONCLUSÃO: O espelho de Glatzel demonstrou não ser um instrumento confiável para a avaliação da permeabilidade nasal na amostra investigada, exceto nos casos de grande obstrução nasal, ou seja, pacientes cirúrgicos e também alérgicos. Não foram observadas correlações com as variáveis: sexo e faixa etária.
Introdução da comunicação suplementar e alternativa na terapia com afásicos
Authors: Galli Juliana Ferreira Marcolino , Oliveira Jáima Pinheiro de , Deliberato Débora
Published: October 2009

Sabe-se que o tratamento fonoaudiológico de pacientes com afasia severa é limitado. A ausência de fala articulada, algumas vezes, impede o diagnóstico da afasia. O paciente "grave" pode não falar devido à inabilidade de articulação, como ocorre na disartria e/ou apraxia. Essa ausência de fala não permite afirmar se a linguagem está comprometida. O uso da comunicação suplementar e alternativa tem sido um método eficaz na reabilitação desses pacientes. Esse estudo visou descrever o uso da comunicação suplementar e alternativa associada a outras modalidades de linguagem (escrita, gestos), a partir do relato de dois casos de afasia. A análise dos dados foi composta por dois blocos: a introdução da comunicação suplementar e alternativa no diálogo; e o uso da leitura e escrita associado aos símbolos. A comunicação suplementar e alternativa foi um apoio para a oralidade, leitura e escrita dos pacientes.
Modelo de oposições múltiplas modificado: abordagem baseada em traços distintivos
Authors: Pagliarin Karina Carlesso , Ceron Marizete Ilha , Keske-Soares Márcia
Published: October 2009

O objetivo deste trabalho foi propor uma abordagem com enfoque em traços distintivos para o Modelo de Oposições Múltiplas e testar sua aplicação em um sujeito falante do Português Brasileiro. O Modelo foi aplicado em um sujeito do sexo masculino, com desvio fonológico moderado-severo e idade de seis anos e meio. Após avaliação fonológica, procedeu-se à seleção dos sons-alvo. Considerou-se o sistema fonológico inicial, bem como os traços distintivos alterados ([+voz], [+soante], [+aproximante], [coronal/±anterior], [-contínuo]). Os traços com maior número de alterações eram [+voz, +soante, +aproximante], justificando a escolha dos seguintes sons-alvo para tratamento: /r/ x /l/ x // x // x /z/, em onset medial.Tendo como base a aplicação desse modelo em falantes do inglês, percebeu-se a necessidade de introduzir alguns procedimentos, como: a escolha dos sons-alvo a partir dos traços distintivos alterados e a estrutura da sessão terapêutica. Ao final, o sujeito foi reavaliado a fim de verificar as aquisições no sistema fonológico. Após dez sessões de fonoterapia,o sujeito adquiriu os fonemas /l, , , z/, generalizando-os para outras posições na palavra (/Z/ e /l/ em onset inicial). Verificou-se, também, a ocorrência de generalização para a mesma classe e para outras classes de sons (/b/, /d/, /g/, /v/). No entanto, o fonema /r/ não foi adquirido. Esta proposta mostrou-se efetiva, pois o sujeito apresentou melhora em seu sistema fonológico com poucas sessões terapêuticas. Pôde-se observar que o Modelo de Oposições Múltiplas, utilizando a abordagem com base em traços distintivos é eficaz, pois favoreceu diversas mudanças fonológicas.
Mapping and evaluation of the state of conservation of the vegetation in and surrounding the Chapada Diamantina National Park, NE Brazil
Authors: Funch Roy Richard , Harley Raymond Mervyn , Funch Ligia Silveira
Published: October 2009

The Chapada Diamantina National Park (CDNP) was created in the midst of a densely populated area, and significant sections of the reserve are still undergoing processes of natural regeneration after intensive diamond mining activities were initiated in the mid-1800's. An up-to-date vegetation map was needed in order to indicate the types and distribution of regional vegetation assemblages in an easily interpretable manner and at an appropriate planning scale that could be easily consulted by decision makers and other interested groups at all levels of conservation (and development) planning. A vegetation map of the Chapada Diamantina National Park, and the areas immediately surrounding it, was prepared that: 1) delimits, describes, and maps the regional vegetation assemblages; 2) provides an indication of the degree of conservation of the mapped vegetation; 3) develops this information in a format that facilitates continued updating and revision as more information becomes available, enabling the monitoring of the evolution of the Park lands, and; 4) presents this information in a manner that can be easily interpreted and used for planning, management and conservation purposes. The resulting vegetation map revealed intensive anthropogenic disturbances in forested, savanna, and semi-arid areas subjected to intensive agricultural use outside of the Park boundaries. The National Park lands are generally well preserved but burning has replaced formerly extensive forest areas with open sedge meadows. In spite of intensive modification of the regional vegetation, two well preserved areas with high priority for conservation efforts beyond the National Park limits were identified and characterized. The vegetation mapping of the park itself can aid in the preparation of its management plan and in the reformulation of the existing boundaries of that reserve.
Description of two new species of Sycorax Curtis (Diptera, Psychodidae, Sycoracinae) from the Atlantic Rain Forest of Espírito Santo, Brazil
Authors: Santos Claudiney Biral dos , Bravo Freddy
Published: October 2009

Two new species of Sycorax Curtis from the Atlantic Rain Forest of Espírito Santo, S. cariacicaensis Santos & Bravo sp. nov. and S. espiritosantensis Santos & Bravo sp. nov., are described and illustrated.
[NO TITLE AVAILABLE]
Authors: Kitahara Marcelo Visentini
Published: October 2009

A pesca demersal voltada as espécies de peixes (i.e. Lophius gastrophisus, Urophisys brasiliensis, Genipterus brasiliensis) e crustáceos (Chaceon ramosae e Chaceon sp.), com grande valor comercial no talude continental superior do sul do Brasil aumentou significativamente nas últimas décadas. A compilação de todos os dados até então publicados acerca dos pontos de ocorrência dos corais escleractíneos azooxantelados em águas sul-brasileiras entre 24° e 35° S, sobrepostos com as principais áreas de atuação das quatro modalidades de pesca demersais (arrasto de profundidade, emalhe e espinhel de fundo e covos), demonstrou que as frotas em questão vêm utilizando as áreas com ocorrência de corais, como principais áreas de esforço, indicando que os recifes de profundidade possuem elevada importância ecológica perante os ecossistemas da plataforma e talude continental, sendo importantes reservatórios da biodiversidade marinha profunda. Entretanto, desde as fases iniciais desta exploração evidenciou-se através de relatos de observadores de bordo, a captura, como "bycatch", de grandes quantidades de corais de profundidade. Desta maneira, visando não só apenas a proteção dos ecossistemas coralíneos de profundidade, mas também a sustentabilidade econômica da pesca, é recomendada a criação de áreas de exclusão da pesca demersal em locais com ocorrência de Scleractinia azooxantelados.
Ácaros em fruteiras e outras plantas no Estado de Amapá
Authors: Mineiro Jeferson Luiz de Carvalho , Silva Wilson Rodrigues da , Silva Ricardo Adaime da
Published: October 2009

Este trabalho teve como objetivo registrar as espécies de ácaros que ocorrem em frutíferas e outras plantas de importância econômica no Estado do Amapá. O levantamento foi realizado nos municípios de Macapá e Calçoene. Nove espécies de plantas pertencentes a sete famílias foram estudadas, tendo sido identificados 226 espécimes de ácaros, das famílias Ascidae, Phytoseiidae, Cunaxidae, Eriophyidae, Stigmaeidae, Tarsonemidae, Tenuipalpidae, Tetranychidae e Tydeidae. A família Tetranychidae apresentou cinco espécies, tendo sido a de maior riqueza.
Composição, uso de hábitat e estações reprodutivas das espécies de anuros da floresta de restinga da Estação Ecológica Juréia-Itatins, sudeste do Brasil
Authors: Narvaes Patrícia , Bertoluci Jaime , Rodrigues Miguel Trefaut
Published: October 2009

Apresentamos aqui dados sobre a composição de espécies, o uso de hábitat e as estações reprodutivas dos anuros da floresta de restinga da Estação Ecológica Juréia-Itatins, sudeste do Brasil. Entre fevereiro e dezembro de 1993, foram realizadas visitas mensais à área de estudo, com permanência de três ou quatro dias, totalizando 28 dias de trabalhos de campo. Três poças pré-selecionadas foram investigadas diariamente entre 18:00 e 22:30 horas, quando foi estimado o número de machos vocalmente ativos nas agregações observadas, tentando-se localizá-los visualmente em seus substratos característicos de vocalização. A fauna é composta por 20 espécies, a maior riqueza já registrada em um ambiente de restinga do Brasil. De acordo com os critérios da IUCN, oito dessas espécies possuem populações em declínio, devido principalmente à perda de hábitat. Onze espécies apresentaram machos em atividade de vocalização e reprodução nas poças monitoradas mensalmente durante todo o período de estudo; a maioria dos hilídeos apresentou segregação vertical em seus sítios de vocalização sobre a vegetação marginal. Scinax hayii e S. littoralis foram consideradas de reprodução contínua, mas o período reprodutivo da maior parte das espécies mostrou-se associado à estação chuvosa. A alta riqueza de espécies observada na área e a indicação de declínios populacionais de algumas espécies em outras regiões sugerem que a região da Juréia apresenta uma grande relevância como área de preservação de anuros.
Consumo de frutos e abundância de Tucano Toco (Ramphastos toco) em dois hábitats do Pantanal Sul
Authors: França Leonardo Fernandes , Ragusa-Netto Jose , Paiva Luciana Vieira de
Published: October 2009

Tucano Toco (Ramphastos toco) é um dos grandes frugívoros de dossel, tanto de florestas contínuas quanto ambientes semi-abertos. No Pantanal Sul o Tucano Toco é comum em paisagens que intercalam ambientes fechados e abertos. Neste estudo avaliamos a abundância de Tucano Toco em capões de mata e mata ciliar, bem como a produção e consumo de frutos carnosos durante a estação seca. Apenas seis espécies frutificaram em capões de mata, e cinco em mata ciliar. Nos capões de mata a maior abundância do gênero Ficus, cuja frutificação foi assincrônica, proporcionou disponibilidade constante de frutos. Na mata ciliar a oferta de frutos carnosos foi variável e as figueiras foram raras e não foram detectadas pelo método de quadrante centrado. Nos dois hábitats os tucanos exploraram frutos de Cecropia pachystachya, Genipa americana e Ficus. A ocorrência de Tucano Toco foi sempre maior em capões de mata do que em mata ciliar, sendo mais elevada em um dado hábitat, quando pelo menos duas espécies disponibilizavam frutos carnosos. A maior regularidade na ocorrência dos tucanos em capões de mata pode ter sido conseqüência da oferta constante de frutos carnosos, a qual ocorreu devido à presença das espécies do gênero Ficus neste hábitat. Porém, a presença da espécie nos hábitats avaliados deve decorrer da combinação de todos os frutos comuns na sua alimentação.
Micro-himenópteros associados com galhas de Cecidomyiidae (Diptera) em Restingas do Estado do Rio de Janeiro (Brasil)
Authors: Maia Valeria Cid , Azevedo Maria Antonieta Pereira de
Published: October 2009

Os microhimenópteros são muito freqüentes em galhas de Cecidomyiidae (Diptera) e representam o principal inimigo natural dessa família de Diptera. Apesar de sua importância ecológica, pouco se conhece sobre a composição faunística dessa guilda de parasitóides em ambientes de Restinga. A coleção de micro-himenópteros do Museu Nacional abriga um grande número de exemplares coletados ao longo de 16 anos de coleta e identificados em nível de família. Inclui representantes de Aphelinidae, Bethylidae, Braconidae, Elasmidae, Encyrtidae, Eulophidae, Eupelmidae, Eurytomidae, Mymaridae, Platygastridae, Pteromalidae, Scelionidae, Tanaostigmatidae, Torymidae e Signophoridae, totalizando 15 famílias. Esses micro-himenópteros estão associados com 45 espécies de plantas hospedeiras (35 gêneros e 25 famílias) e 26 gêneros de Cecidomyiidae, sendo mais freqüentes em galhas de Asphondylia, Bruggmannia, Clinodiplosis, Dasineura, Lopesia, Neolasioptera e Stephomyia. A grande maioria é parasitóide, mas alguns representantes (Tanaostigmatidae e algumas espécies de Torymidae e Eulophidae) são fitófagos inquilinos de galhas. Eulophidae, Eupelmidae e Platygastridae destacaram-se como as famílias de Hymenoptera mais freqüentes, ocorrendo em um número maior de famílias, gêneros e espécies de plantas. Myrtaceae, Fabaceae e Malpighiaceae destacaram-se como as famílias de planta com maior número de famílias de Hymenoptera associadas. Cerca de 135 registros novos de parasitóides em galhas de Cecidomyiidae são apresentados.
Chromosome number and microsporogenesis of two accessions of Brachiaria dura Stapf (Poaceae)
Authors: Risso-Pascotto Claudiceia , Pagliarini Maria Suely , Valle Cacilda Borges do
Published: October 2009

The two accessions of B. dura analyzed (DU01 and DU02) are hexaploid (2n = 6x = 54), derived from x = 9. Meiotic abnormalities, such as precocious chromosome migration to the poles, laggards and micronuclei, were recorded in low frequency in both accessions. The few multivalent chromosome association at diakinesis and meiotic stability suggested that hexaploidy probably resulted from chromosome doubling. In DU02, chromosome transfer (cytomixis) among meiocytes, involving part or the entire genome was observed. The implication of these findings for the Brachiaria breeding is discussed.
Range extension of the Peale's Free-tailed Bat Nyctinomops aurispinosus (Molossidae) in Brazil
Authors: Bianconi Gledson Vigiano , Gregorin Renato , Carneiro Daniel Carvalho
Published: October 2009

There is a lack of knowledge of the biology and distribution of Nyctinomops aurispinosus. Herein, we report the southernmost record of this species, from the city of Curitiba (25° 25' S and 49° 15' W, 920 m), state of Paraná, Brazil, and summarize its distribution in South America.
Spontaneous splenic rupture in a patient receiving thrombolytic therapy
Authors: Revesz Elizabeth , Grimaldi John A. , Clark Elizabeth T. , Podbielski Francis J.
Published: October 2009

We describe the case of a 67-year-old female patient with a history of femoral-distal bypass graft with sudden onset of unremitting leg pain, who had recently received tissue plasminogen activator (t-PA). The patient reported non-compliance with her warfarin regimen. Angiography revealed occlusion of the bypass graft. Infusion of t-PA was performed via a right femoral artery approach. On hospital day two, the patient developed nausea and abdominal pain with associated hypotension. A CT scan showed a massive intra-abdominal and pelvic free fluid consistent with blood. The spleen was enlarged and fluid noted around the liver. At laparotomy, a grade III splenic laceration at the hilum was identified and a splenectomy performed. The patient recovered completely. Although rare, spontaneous splenic rupture should be considered in the differential diagnosis of patients undergoing thrombolytic therapy who develop signs of hemodynamic instability.
Race and Unhealthy Behaviors: Chronic Stress, the HPA Axis, and Physical and Mental Health Disparities Over the Life Course
Authors: Jackson James S. , Knight Katherine M. , Rafferty Jane A.
Published: October 2009

Objectives. We sought to determine whether unhealthy behaviors play a stress-buffering role in observed racial disparities in physical and mental health.

Methods. We conducted logistic regressions by race on data from the first 2 waves of the Americans' Changing Lives Survey to determine whether unhealthy behaviors had buffering effects on the relationship between major stressors and chronic health conditions, and on the relationship between major stressors and meeting the criteria for major depression.

Results. Among Whites, unhealthy behaviors strengthened the relationship between stressors and meeting major-depression criteria. Among Blacks, however, the relationship between stressors and meeting major-depression criteria was stronger among those who had not engaged in unhealthy behaviors than among those who had. Among both race groups there was a positive association between stressors and chronic health conditions. Among Blacks there was an additional positive association between number of unhealthy behaviors and number of chronic conditions.

Conclusions. Those who live in chronically stressful environments often cope with stressors by engaging in unhealthy behaviors that may have protective mental-health effects. However, such unhealthy behaviors can combine with negative environmental conditions to eventually contribute to morbidity and mortality disparities among social groups.
CHANGES in SKIN TANNING ATTITUDES Fashion Articles and Advertisements in the Early 20th Century
Authors: Martin Jo M. , Ghaferi Jessica M. , Cummins Deborah L. , Mamelak Adam J. , Schmults Chrys D. , Parikh Mona , Speyer Lark-Aeryn , Chuang Alice , Richardson Hazel V. , Stein David , Liégeois Nanette J.
Published: October 2009

Historical reviews suggest that tanning first became fashionable in the 1920s or 1930s. To quantitatively and qualitatively examine changes in tanning attitudes portrayed in the popular women's press during the early 20th century, we reviewed summer issues of Vogue and Harper's Bazaar for the years 1920, 1927, 1928, and 1929. We examined these issues for articles and advertisements promoting skin tanning or skin bleaching and protection. We found that articles and advertisements promoting the fashionable aspects of tanned skin were more numerous in 1928 and 1929 than in 1927 and 1920, whereas those promoting pale skin (by bleaching or protection) were less numerous. These findings demonstrate a clear shift in attitudes toward tanned skin during this period.
Improving Injectivity To Fight Gravity Segregation in Gas Enhanced Oil Recovery
Authors: Jamshidnezhad M.. , Shen C.. , Kool P.. , Mojaddam Zadeh A.. , Rossen W.R.. R.
Published: October 2009

Models for gravity segregation in gas enhanced oil recovery (EOR) indicate that the distance injected gas and water travel together before complete segregation scales with the injection rate Q. Therefore, in cases where injection pressure is limiting, increasing injectivity can improve sweep efficiency. We examine several strategies. Reducing skin resulting from damage at the wellbore face directly increases volumetric sweep of gas. Even in the absence of damage at the wellbore face, most of the injection pressure is dissipated near the injection well, but most of segregation of gas and water occurs much further from the well. Therefore, if injection pressure is limited, increasing mobility near the injection well has a large impact on Q, with a direct benefit in delaying gravity segregation. There is also a relatively small increase in gravity segregation in the near-well region. An analytical model for gravity segregation in homogeneous reservoirs can be extended to a case where permeability is stimulated within a cylindrical region inside a larger cylindrical reservoir. The effect of this stimulation in increasing Q at fixed injection pressure can be estimated as well. One can increase the volume swept by gas before segregation by as much as 170%, though a large volume must be stimulated to reach this optimum.

The model represents schematically a number of ways proposed in gas EOR for delaying segregation beyond the possibilities with uniform, steady coinjection of Newtonian fluids: alternate injection of gas and liquid [water alternating gas (WAG) or surfactant alternating gas (SAG) with foam]; injection of gas above water; and injection of shear-thinning foam. In all these cases, the process gives higher mobility near the well, allowing an increase in injection rate, and thereby increases the distance to the point of segregation.

The model can be extended directly to the case of shear-thinning (power-law) foam. One obtains a differential equation for the segregation process, in place of the algebraic equation that results for Newtonian fluids. In the limit of extremely shear-thinning behavior, it is possible to double the distance to the point of segregation with no increase in injection pressure. The model can also be applied to foams that are shear-thinning only at high superficial velocity (i.e., near the well). Simulations fit the theoretical prediction well.
Modeling of an Underbalanced-Drilling Operation Using Supercritical Carbon Dioxide
Authors: Al-Adwani Faisal , Langlinais Julius , Hughes Richard
Published: October 2009

A mechanistic model of an underbalanced-drilling (UBD) operation using carbon dioxide (CO2) is developed in this study. The use of carbon dioxide in UBD operations eliminates some of the operational difficulties inherent with gaseous drilling fluids, such as generating enough torque to run a downhole motor. The unique properties of CO2, both inside the drillpipe and in the annulus, are shown in terms of optimizing the drilling operation by achieving a low bottomhole pressure range. Typically, CO2 becomes supercritical inside the drillpipe at this high density; thus, it can generate enough torque to run a downhole motor. As the fluid exits the drill bit, it evaporates to a gas, hence achieving the required low density for UBD. The latest CO2 equation of state (EOS) to calculate the required thermodynamic fluid properties is used. In addition, a heat-transfer model that takes into account varying properties of both pressure and temperature has been developed. A marching algorithm procedure is developed to calculate the circulating fluid pressure and temperature, taking into account the varying parameters. Both single-phase CO2 and a mixture of CO2 and water have been studied to show the effect of produced water on corrosion rates. The model also is capable of handling different drillpipe and annular geometries.
Use of Dynamic Simulation To Assist Commissioning and Operating a 65-km-Subsea-Tieback Gas Lift System
Authors: Salman Yaser , Wittfeld Chad , Lee Adrian , Yick Chevy , Derkinderen Wim
Published: October 2009

The Penguins field comprises of a cluster of reservoirs in the northern North Sea. The need for gas lift was foreseen during the early stages of field-development planning. Five oil wells were completed for gas lift service. A 65-km 4-in. gas lift line was laid in 2006, running alongside the production line and tied into the drill centers by flexible 2-in. jumpers.

Because of the unconventionally long distance of the field from the platform, it was necessary to carry out transient modeling of the full commissioning and gas lift startup process. Particular attention was required, both in design and operating procedure, to avoid hydrates and excessive velocities in the high-pressure, low-temperature system.

Dynamic simulation with the industry-renowned transient software package (OLGA v5.1 2006) has proved to be valuable for the commissioning of this gas lift system. It also explained discrepancies between anticipated behavior of the shear orifice valve and the actual behavior seen in the field.

The overall project outcome was a success, with excellent improvements in field stability and production. The project was justified on the basis of kickoff capability only, but continuous gas lift is required to maintain stable flow from all of the wells.
Resolving Created, Propped, and Effective Hydraulic-Fracture Length
Authors: Cipolla C. L. , Lolon E. P. , Mayerhofer M. J.
Published: October 2009

Recent advances in hydraulic-fracture-mapping technologies have provided a wealth of information on the created fracture length in numerous geologic settings. Before having such measurements, fracture length was estimated using "uncalibrated" fracture-propagation models, but there was significant uncertainty in the results that cascaded into subsequent production analyses. However, we also need to understand how the created fracture length relates to the location of proppant in the fracture and to the producing or effective length to evaluate well performance and improve stimulation designs. Unfortunately, the advanced fracture-mapping technologies that provide accurate measurements of the created fracture length cannot provide any insights (yet) into the propped and effective fracture lengths. Advanced production-data analyses (PDAs), pressure-transient testing, and/or numerical reservoir modeling are required to determine the effective fracture length.

This paper begins with a comparison of the strengths, weaknesses, and limitations of fracture modeling, PDA, pressure-transient analysis (PTA), and numerical reservoir modeling to estimate effective fracture length and conductivity. This work also evaluates how the complexities (in the hydraulic fracture) associated with non-Darcy flow, multiphase flow, and complex fracture geometries affect the results from the various techniques. This work documents the significant differences in "effective" fracture length that, in many cases, can result from each technique and how these uncertainties can impact fracture treatment designs and field-development decisions.

The paper concludes with several field case histories that illustrate the integration of multiple technologies to determine the created, propped, and effective fracture length. The case histories illustrate the dramatic differences in created and effective fracture length that can occur in some reservoirs, while also showing that in some cases, effective fracture lengths can be very similar to the created length (and quite long). Integrating the results from multiple diagnostic techniques in a consistent and coherent manner can provide significant insights into created, propped, and effective fracture length that are otherwise unattainable from each technique alone.
Phosphorus Sorption as Affected by Soil Properties and Termite Activity in Eastern and Southern Africa
Authors: Mamo Martha , Wortmann Charles
Published: October 2009

Phosphorus is often the limiting nutrient to crop production in eastern Africa. Efficient management of P requires an understanding of the factors affecting availability of soil native P and applied fertilizer P. The objectives of this study were (i) to evaluate the relationships between soil properties and P sorption characteristics, and (ii) to assess the effect of termite activities on soil properties and P sorption characteristics. Phosphorus sorption isotherms were determined for 36 soils, including 7 samples from termite mounds and surrounding non‐termite soils from Uganda and Mozambique. Ammonium‐oxalate extractable Al (Alox) was the most important property explaining over 90% of the variation in P sorption maximum (Smax) for Uganda and Mozambique soils. However, for the Ethiopia soils 88% of the variation was explained by Mehlich‐3 extractable Ca, ammonium‐oxalate extractable P (Pox), and sand content. The Smax of Uganda and Mozambique soils increased by 44 to 390% due to increased clay content from termite activities. The higher Smax of termite mounds implies a greater demand for P fertilizer for low P soils but also a higher P storage capacity and reduced risk of P leaching. Termite mound could be considered as a potential soil amendment.
Plant‐Available Calcium Varies Widely in Soils on Serpentinite Landscapes
Authors: McGahan Donald G. , Southard Randal J. , Claassen Victor P.
Published: October 2009

Serpentinitic landscapes are characterized by unusual plant species composition and vegetation patchiness. We hypothesized that soil extractable Ca content is correlated with vegetation Ca concentration and may contribute to the unusual vegetation characteristics. Eleven pedons from California were sampled within soil survey mapping polygons containing the modal location for a classic “serpentine soil.” Soil NH4OAc‐extractable Ca/Mg ratio varied from 0.1 to 1.5 and total elemental Ca/Mg ratio varied from <0.01 to 1.9. Soil extractable Ca content was influenced by parent material mineralogy: soils with a Ca/Mg ratio of 0.2 or less were derived from serpentinite parent materials with only trace Ca‐bearing minerals; soils with a Ca/Mg ratio >1.0 were derived from non‐serpentinite parent materials, and soils with a Ca/Mg ratio from 0.2 to 1.0 were derived from serpentinite parent material that had minor amounts of accessory Ca‐bearing minerals. Based on greenhouse studies, the Ca concentration of the leaf of the grass Vulpia microstachys (Nutt.) Monro correlated better with soil‐extractable Ca (r2 = 0.69, P < 0.01) than with total elemental analysis Ca (r2 = 0.40, P > 0.05). The shallow soil depths of the pedons, together with the generally high coarse fragment content, limit the soil volume available to roots. Pedons with the highest extractable Ca/Mg (1.34 and 1.89) also had the greatest extractable Ca pool, 1169 and 394 g m−2, respectively. Among the 11 pedons, extractable Ca/Mg ratio, extractable‐Ca pool, and the distribution of the Ca pool within the pedon all varied, and these variables were important determinants of plant performance, as determined by leaf Ca content. Of these variables, soil extractable‐Ca content was the best determinant of plant performance as indicated by leaf Ca concentration.
Electromagnetic Induction Sensor Data to Identify Areas of Manure Accumulation on a Feedlot Surface
Authors: Woodbury Bryan L. , Lesch Scott M. , Eigenberg Roger A. , Miller Daniel N. , Spiehs Mindy J.
Published: October 2009

A study was initiated to test the validity of using electromagnetic induction (EMI) survey data, a prediction‐based sampling strategy, and ordinary linear regression modeling to predict spatially variable feedlot surface manure accumulation. A 30‐ by 60‐m feedlot pen with a central mound was selected for this study. A Dualem‐1S EMI meter (Dualem Inc., Milton, ON, Canada) pulled on 2‐m spacing was used to collect feedlot surface apparent electrical conductivity (ECa) data. Meter data were combined with global positioning system coordinates at a rate of five readings per second. Two 20‐site sampling approaches were used to determine the validity of using EMI data for prediction‐based sampling. Soil samples were analyzed for volatile solids (VS), total N (TN), total P (TP), and Cl− A stratified random sampling (SRS) approach (n = 20) was used as an independent set to test models estimated from the prediction‐based (n = 20) response surface sample design (RSSD). The RSSD sampling plan demonstrated better design optimality criteria than the SRS approach. Excellent correlations between the EMI data and the ln(Cl−), TN, TP, and VS soil properties suggest that it can be used to map spatially variable manure accumulations. Each model was capable of explaining >90% of the constituent sample variations. Fitted models were used to estimate average manure accumulation and predict spatial variations. The corresponding prediction maps show a pronounced pen design effect on manure accumulation. This technique enables researchers to develop precision practices to mitigate environmental contamination from beef feedlots.
Nitrogen Fertilizer Sources and Timing before Flooding Dry‐Seeded, Delayed‐Flood Rice
Authors: Norman R. J. , Wilson C. E. , Slaton N. A. , Griggs B. R. , Bushong J. T. , Gbur E. E.
Published: October 2009

Urea is the primary N source used for the large preflood N application in delayed‐flood rice (Oryza sativa L.) production in the southern United States. Urea is prone to substantial NH3 volatilization losses, however, if fields are not flooded quickly. Most delayed‐flood rice fields require 5 to 10 d to flood. Consequently, a study was conducted to evaluate the use of less NH3–volatile N sources for the preflood N application. The objectives were to evaluate the NH3 volatilization loss and impact on N uptake and rice yield when urea, urea plus the urease inhibitor N‐(n‐butyl)thiophosphoric triamide (NBPT), (NH4)2SO4, or a urea‐(NH4)2SO4 (UAS) blend were applied preflood and a flood established 1, 5, or 10 d after N application. When flooding was delayed for 5 or 10 d after N application, NH3 volatilization was the least for urea + NBPT (2–10%) and (NH4)2SO4 (4–5%) and they produced the highest rice N uptake and yield. The UAS blend that had NH3 volatilization losses (11–15%) at 5 and 10 d after application that were intermediate between urea (17–24%) and (NH4)2SO4 or urea + NBPT also had N uptake and grain yield intermediate between these N sources. Urea should only be used if ∼2 d are required to flood a field. If 3 to 5 d are required to flood a field, then UAS has some merits but it is not as consistent as (NH4)2SO4 or urea + NBPT. When >5 d are required to flood, (NH4)2SO4 or urea + NBPT should be used.
On the Definition of the Natural Capital of Soils: A Framework for Description, Evaluation, and Monitoring
Authors: Robinson David A. , Lebron Inma , Vereecken Harry
Published: October 2009

The unknown consequences and potential impacts of mankind's ability to destroy, alter, or manipulate ecosystems on a vast scale drives our need to better understand the earth system. A fundamental challenge for soil science in the 21st century is to understand the role of soil processes in relation to the function of the earth system. The rationale for developing a definition of soil natural capital stems from the premise that we value ‘things’ based on their perceived value to human well‐being. As a consequence, ignorance of the value of a resource, or system, may lead to its neglect and omission from decision making. Therefore, there is a need to develop a definition of soil natural capital, fitting within a broad framework, which can be used to assess soil ecosystem services that contribute to the function of the earth system. Though various definitions of soil natural capital have been proposed, mostly in the agricultural context, it still remains a nebulous and ill‐defined term. The objective of this paper is to develop an embracing definition of soil ‘natural capital’ focusing on (i) mass, (ii) energy, and (iii) organization/entropy. Mass is further subdivided into solid, liquid and gas phases, and organization into physicochemical, biotic, and spatiotemporal structure. We differentiate between two aspects of capital, the quantity and the quality. As a result of our definition, soil moisture, temperature, and structure emerge as valuable stocks, alongside the more traditionally viewed stocks such as inorganic (mineralogy, texture) and organic materials (OM content). We go on to demonstrate how natural capital fits within the ecosystem services framework, and how using integrated valuation and process based models it can be evaluated. Finally we discuss measurement and monitoring needs that fit with this vision of evaluation.
Controls on the Spatial Patterns of Carbon and Nitrogen in Adirondack Forest Soils along a Gradient of Nitrogen Deposition
Authors: Bedison James E. , Johnson Arthur H.
Published: October 2009

We sampled 42 permanent vegetation plots in the Adirondack Mountains, NY to characterize the spatial patterns of, and controls on soil C and N contents. Average C (24 kg m−2) and N (1.1 kg m−2) contents of the combined organic and mineral horizons were high for northeastern U.S. forests. Contrary to our expectations, whole‐profile C and N amounts were not different among northern hardwood (NH), spruce‐fir (SF), and pine‐dominated (PW) plots. Most of the C and N were stored in organic horizons in the high‐elevation SF plots, and in the mineral horizons in NH and PW plots. Regression analyses of the pooled set of sites revealed that the factors that explained the most variability in soil C and N contents were different for organic and mineral horizons and differed between forest types. Overall, growing season degree‐days (GSDD) was the variable most closely correlated with C and N contents in both organic and mineral horizons, and varying combinations of N deposition, conifer importance, and soil texture were the principal secondary influences. Spruce‐fir plots received the most atmospheric N deposition, and multivariate regression tree (MRT) analysis indicated that N deposition rate was the environmental variable that explained the most variation in organic horizon C (sums of squares [SS] explained = 54%) and N (79% SS explained) amounts in these high‐elevation stands. However, even in the unlikely case of 100% retention of the atmospheric inputs of N deposited over the past 50 yr, this source only accounted for a small portion of soil N, and the differences in N among the plots along the deposition gradient. It is likely that differences in GSDD accounted for most of the differences in C and N amounts.
Increased Soil Sorption of Pendimethalin due to Deposition of Guayule‐Derived Detritus
Authors: Williams C. F. , Coffelt T. A. , Watson J. E.
Published: October 2009

Laboratory sorption experiments were conducted to determine the extent to which soil organic matter derived from guayule (Parthenium argentatum A. Gray) residues can affect the sorption of pendimethalin [N‐(1‐ethylpropyl)‐3,4‐dimethyl‐2,6‐dinitrobenzenamine]. Soils where guayule had been grown for 0 to 38 mo were collected for sorption experiments from beneath actively growing plants. An additional treatment was collected before planting cotton (Gossypium hirsutum L.) in a field 1 yr after the final harvest of guayule that had been grown for 36 mo was also included. Continuous guayule cultivation resulted in a modest increase in soil organic C from 0.29% (±0.01%) to 0.76% (±0.03%) after 38 mo of production. Pendimethalin sorption to the soil increased with increasing guayule organic deposition as measured by time under cultivation. Soils where guayule was grown for 38 mo had an organic C distribution coefficient, KOC, 23 times greater than the control soil where guayule had not been grown (389,400 vs. 16,900 L kg−1). In the treatment before planting cotton, however, the combination of time and cultivation resulted in a reduction of KOC from 389,400 to 21,500 L kg−1 The use of pendimethalin in a guayule–cotton rotation requires sufficient time and primary tillage before planting cotton. In addition, the use of pendimethalin during regrowth of guayule from the stump following harvest may require higher application rates to control weeds. Adsorption of pendimethalin to soil using batch equilibrium indicated that soil beneath actively growing guayule has a higher sorption capacity for pendimethalin than soil without guayule.
Assessment of Potassium Supply for Corn by Analysis of Plant Parts
Authors: Mallarino Antonio P. , Higashi S.L.
Published: October 2009

Tissue testing of corn (Zea mays L.) ear leaves often is used to diagnose K deficiencies. However, little attention has been given to study how testing of different corn tissues evaluates K supply especially in the optimum to excess range. We evaluated tissue tests for corn based on the K concentration of young plants (V5 to V6), ear leaves at silking, lower stalks at maturity (sections cut from 15 to 35 cm aboveground), and grain. Twenty‐eight field trials were conducted in Iowa during 2 yr with fertilizer rates of 0, 56, 112, and 168 kg K ha−1 Initial soil‐test K (STK) by the ammonium acetate extractant (15‐cm sampling depth, air‐dried samples) was 80 to 266 mg K kg−1 across sites. Fertilizer K increased grain yield at one site testing 84 mg K kg−1; and increased the K concentration of plants, leaves, stalks, and grain at 11, 13, 21, and 5 sites, respectively. Published critical K concentrations for corn plants and leaves would have incorrectly indicated deficient soil K supply for yield in many sites. There were upper limits in plants, leaves, and grain K concentrations response to K supply that varied among sites. The limits occurred at STK values of 123, 140, and 148 mg kg−1, respectively, which are near STK values optimum for grain yield. The lack of an upper limit in corn stalks shows promise for using this tissue to assess K availability from deficiency to luxury uptake or excess. However, the large site‐dependent variability in the stalk K concentrations should be recognized as a limitation.
Boron Sorption on Wastewater Dissolved Organic Matter: pH Effect
Authors: Keren R. , Communar G.
Published: October 2009

Although it is well known that B interacts with organic matter, no information is available yet on B adsorption by dissolved organic matter (DOM) from treated sewage effluent. This study aimed to determine the effect of pH on B adsorption by DOM in sewage effluent, and to develop a B adsorption model for DOM as a function of pH. The DOM used in this study was separated from effluent from a municipal wastewater treatment plant. The B adsorption isotherms for the DOM were determined at various pH levels ranging from 5.1 to 10.9. Boron adsorption by DOM increased significantly as the pH increased from 5.8 to 9.25, and maximized at pH 9.3. The B adsorption values at any given constant pH, as calculated by using the Langmuir adsorption equation fitted every single adsorption isotherm well, but the adsorption parameters kB–DOM and bmDOM were both pH dependent. The competitive adsorption model simulated well B adsorption by DOM only at the high pH range, but failed at the lower range. The deviation between the predicted values and the experimental data in the low pH range is probably due to changes in DOM structure and acidic functional groups content. Good agreement between calculated and experimental results at the lower pH range was obtained by introducing a correction factor in the competitive adsorption model to account for these changes.