bluuebunny/crossref_metadata_2025 huggingface dataset:
Grupos de pesquisa em história da enfermagem: a realidade brasileira
Authors: Padilha Maria Itayra , Borenstein Miriam Susskind , Carvalho Maria Aline Lima , Ferreira Aline Coelho
Published: March 2012

Este estudo tem por objetivo analisar as atividades dos grupos de pesquisa em história da enfermagem existentes no Brasil e sua articulação com os cursos de graduação e pós-graduação em enfermagem. É um estudo exploratório qualitativo descritivo documental, realizado no período de julho de 2008 a março de 2010. Foram identificados 34 grupos de pesquisa com pelo menos uma de suas linhas de pesquisa em história da enfermagem. Os resultados indicaram que os grupos têm produzido um vasto material bibliográfico, linhas de pesquisa e ampla participação de estudantes de graduação e pós-graduação. Verifica-se também que ainda não há uma rede de comunicação entre os grupos da mesma linha de pesquisa. Conclui-se que é necessário trabalhar na interdisciplinaridade e no fortalecimento de algumas linhas de pesquisa que sustentem o conhecimento em história da enfermagem brasileira.
Utilização de metodologia ativa no ensino e assistência de enfermagem na produção nacional: revisão integrativa
Authors: Sobral Fernanda Ribeiro , Campos Claudinei José Gomes
Published: March 2012

Esta é uma revisão integrativa de literatura cujo objetivo foi identificar e analisar publicações científicas sobre o uso das metodologias ativas no ensino e assistência de enfermagem no Brasil. O levantamento bibliográfico incluiu publicações nacionais, no período de 1999 a 2009. Foram verificadas as bases de dados LILACS, BDENF, MEDLINE e a biblioteca eletrônica SciELO. Foram selecionados 28 artigos. Os resultados e a análise mostraram a problematização como a principal metodologia ativa utilizada, a falta de referenciais teóricos para planejar a ação pedagógica e o uso excessivo de técnicas de ensino que nem sempre caracterizam a inovação do método. Conclui-se que a implementação das metodologias inovadoras ainda carece de mais estudos e necessita de maior investimento em pesquisa e divulgação sobre o assunto.
Produção científica sobre liderança no contexto da enfermagem
Authors: Amestoy Simone Coelho , Backes Vânia Marli Schubert , Trindade Letícia de Lima , Canever Bruna Pedroso
Published: March 2012

O estudo tem por objetivo identificar a produção científica sobre liderança no contexto da enfermagem produzida nos últimos 10 anos (1999-2008). Trata-se de uma revisão bibliográfica na base de dados LILACS, na qual foram incluídos trabalhos publicados no formato de artigos, teses, dissertações, editoriais, apresentação de trabalho em eventos; em português, inglês ou espanhol; disponíveis na íntegra no formato eletrônico. Optou-se pela construção de um formulário para registrar os dados das produções, entre eles: referência, procedência dos manuscritos, ano, categoria, objetivos, metodologia e referencial teórico. Encontraram-se 57 publicações, das quais houve o predomínio de artigos originais, do tipo descritivo, no âmbito hospitalar e a escassa utilização de Teorias de Liderança fundamentando os estudos. A pesquisa aponta para a necessidade de adotar programas de desenvolvimento de líderes e projetos de educação permanente nos serviços de saúde, a fim de prepará-los para aplicar a liderança na enfermagem.
Control system for forced-air cooling of horticultural products
Authors: Silva João C. T. R. da , Mederos Bárbara J. T.
Published: March 2012

This work is a study of the implementation of a classical controller using a tuning method referred to as IMC (Internal Model Control) and aimed at the reduction of electrical energy consumption by the appropriate relation between energy consumption and the cooling time with forced air. The supervisory system installed was able to manipulate the variable of frequency of the signal power of the exhaust fan engine (forced air module), to accelerate or decelerate the loss of heat from the product to be cooled by airflow variation that passes through the mass of the produce. The results demonstrated a reduction in energy consumption from 64% and an increase of only 8% in the cooling time to the system using PI/IMC (Proportional - Integral with IMC) tuning method compared with the system in its operating nominal condition. This PI/IMC control may be implemented directly in a frequency converter, without the need to purchase a computer or PLC (programmable logic controller) to run the dedicated application, increasing its economical viability.
Terrain forms and spatial variability of soil properties in an area cultivatedwith citrus
Authors: Leão Marisol G. A. de , Marques Júnior José , Souza Zigomar M. de , Siqueira Diego S. , Pereira Gener T.
Published: March 2012

The technique of precision agriculture and soil-landscape allows delimiting areas for localized management, allowing a localized application of agricultural inputs and thereby may contribute to preservation of natural resources. Therefore, the objective of this work was to characterize the spatial variability of chemical properties and clay content in the context of soil-landscape relationship in a Latosol (Oxisol) under cultivation of citrus. Soil samples were collected at a depth of 0.0-0.2 m in an area of 83.5 ha planted with citrus, as a 50-m intervals grid, with 129 points in concave terrain and 206 points in flat terrain, totaling 335 points. Values for the variables that express the chemical characteristics and clay content of soil properties were analyzed with descriptive statistics and geostatistical modeling of semivariograms for making maps of kriging. The values of range and kriging maps indicated higher variability in the shape of concave topography (top segment) compared with the shape of flat topography (slope and hillside segments below). The identification of different forms of terrain proved to be efficient in understanding the spatial variability of chemical properties and clay content of soil under cultivation of citrus.
Performance during post-harvest storage of banana cv. 'prata', 'maçã' and 'nanica' exposed to physical and chemical treatments
Authors: Coelho Silvia R. M. , Werner Simone S. , Poncio Anna P. , Ferreira Letícia , Nóbrega Lúcia H. P.
Published: March 2012

Banana is the most consumed fruit in the world and Brazil is the second largest producer. Despite its global position, Brazil has an average of 40% losses during the post-harvest period. So, this experiment aimed at evaluating the efficiency of post-harvest treatments to improve the storage of banana cultivars cv. 'Prata', 'Maçã' and 'Nanica'. The fruits were acquired at CEASA with green peel, and were submitted to six different treatments: T- immersion in drinking water for 3 minutes (control), H3 - hot water (50 °C for 3 minutes), H8 - hot water (50 °C for 8 minutes), HP - immersion in hypochlorite 0.2% for 3 minutes, OS - immersion in soybean oil 10% for 3 minutes, and OM - immersion in mineral oil 10% for 3 minutes. The fruits were stored at room temperature at about 21 °C for 14 days and evaluated in three periods (1, 7 and 14 days) comparing peel color, flesh/peel ratio, titratable acidity (TA), soluble solids (SS), SS/TA ratio, and pH. The fruits of cv. 'Prata' and 'Maçã' submitted to the treatments H3, H8 and HP ripened at the same time as the control for peel color, which showed increased soluble solids, flesh/peel ratio, acidity and a decrease in pH. On the other hand, the cv. 'Nanica' did not respond significantly different when compared to the applied treatments and the control. The fruits treated with OM and OS were kept green for a longer time for the cultivars 'Prata' and 'Nanica', but there were some changes on peel color due dark spots in 'Prata' banana and a softening aspect in 'Nanica', indicating some level of toxicity of these treatments. Fruits of the 'Maçã' cultivar continued green with the application of mineral oil, without toxicity symptoms. In conclusion, the treatments applied did not show any advantage for storage of these fruits.
Estrutura do dossel, consumo e desempenho animal em pastos de capim-marandu sob lotação contínua
Authors: Paula C.C.L. , Euclides V.P.B. , Montagner D.B. , Lempp B. , Difante G.S. , Carloto M.N.
Published: March 2012

Avaliaram-se o valor nutritivo, a estrutura do dossel, a ingestão de forragem e a produção animal de novilhos em pastos de capim-marandu submetidos a três intensidades de pastejo. O delineamento experimental foi de blocos completos ao acaso, com duas repetições e três intensidades de pastejo, representadas pelas alturas do pasto de 15, 30 e 45cm. Mensalmente, os pastos foram amostrados para as estimativas das características estruturais do dossel e o valor nutritivo da forragem. A ingestão de matéria seca pelos animais foi estimada no verão e no outono de 2008. A oferta de forragem decresceu à medida que aumentou a intensidade de pastejo. Pastos manejados com 15cm de altura apresentaram maior valor nutritivo e estrutura do dossel mais favorável à apreensão de forragem pelos animais. A oferta limitou a ingestão de forragem no pasto com 15cm de altura, consequentemente se verificaram menor ganho de peso e maior taxa de lotação. Foram observados ganhos por área semelhantes nos pastos com 15 e 30cm, e ganhos mais elevados no pasto com 45cm. Durante o período das águas, o capim-marandu deve ser utilizado entre 15 e 30cm de altura sob lotação contínua.
Productive performance of Nile tilapia (Oreochromis niloticus) fed at different frequencies and periods with automatic dispenser
Authors: Sousa R.M.R. , Agostinho C.A. , Oliveira F.A. , Argentim D. , Novelli P.K. , Agostinho S.M.M.
Published: March 2012

The performance of Nile tilapia (Oreochromis niloticus) raised in cages furnished with an automatic dispenser, supplied at different frequencies (once per hour and once every two hours) and periods (daytime, nighttime and both) was evaluated. Eighteen 1.0m³ cages were placed into a 2000m² pond, two meters deep with a 5% water exchange. One hundred and seventy tilapias, with initial weight of 16.0±4.9g, were dispersed into each 1m³ cage and the feed ration was adjusted every 21 days with biometry. Data was collected from March to July (autumn and winter). Significant difference to final weight (P<0.05) among treatments was observed. The increase in feeding frequency improves the productive performance of Nile tilapias in cages and permitted better management of the food. The better feed conversion rate for high feeding frequency (24 times day-1) can result in saving up to 360kg of food for each ton of fish produced, increasing the economic sustenance for tilapia culture and suggesting less environmental pollution.
Hematologia de tilápia-do-nilo alimentada com suplemento à base de algas frente a desafios de estresse agudo e crônico
Authors: Garcia F. , Schalch S.H.C. , Onaka E.M. , Fonseca F.S. , Batista M.P.
Published: March 2012

Avaliou-se o efeito da suplementação com produto à base de algas, ergosan, em dietas para tilápias Oreochromis niloticus, submetidas ao desafio de estresse agudo e crônico sobre as características hematológicas. O ensaio foi realizado com tilápias jovens (15g) em caixas de 500L de capacidade de estocagem, em sistema com recirculação da água, com fluxo constante, na densidade de 35 peixes por caixa. Os peixes foram alimentados com as dietas-teste durante 10 dias e, ao final deste período, voltaram a receber dieta isenta de ergosan, quando foram submetidos aos desafios de estresses agudo e crônico. Utilizou-se o delineamento inteiramente ao acaso (DIC), em esquema fatorial 4x2, sendo testados: quatro porcentagens do suplemento 0; 0,25; 0,5 e 1% de ergosan na ração em dois tipos de estresse, agudo e crônico. Os resultados permitem concluir que os estímulos de estresse aplicados foram capazes de provocar alterações fisiológicas nos peixes, incluindo redução no número de eritrócitos, eritroblastos e leucócitos e aumento do volume corpuscular médio dos eritrócitos. A administração oral de 1% de suplemento durante 10 dias para juvenis de tilápia-do-nilo, em condição de estresse agudo, induz o incremento de 69% no número de trombócitos circulantes.
Presença do vírus da síndrome da mancha branca em crustáceos decápodes silvestres em lagoas costeiras no Sul do Brasil
Authors: Costa S.W. , Fraga A.P.M. , Zamparetti A.S. , Marques M.R.F. , Andreatta E.R.
Published: March 2012

A presença do vírus da síndrome da mancha branca (em inglês WSSV) nas principais espécies de camarões, siris e caranguejos de cinco lagoas que recebem o efluente de fazendas afetadas pela enfermidade foi detectada por nested PCR, e inclusões virais nos camarões por histologia. Pela nested PCR encontrou-se a presença de WSSV em 13 de 16 (81,2%) amostras de camarões da espécie Farfantepenaeus paulensis, em 13 de 14 (92,8%) de Litopenaeus schmitti, em uma de duas de Farfantepenaeus brasiliensis (50%), em 13 de 15 (86,6%) de siri da espécie Callinectes danae e em 11 de 12 (91,6%) de Callinectes sapidus, e não foi detectada no caranguejo Chasmagnathus granulata em 10 amostras. Inclusões características de WSSV foram observadas em três amostras histológicas de 50 (6,0%) no epitélio gástrico e cuticular e nas brânquias de dois exemplares de F. paulensis e um de L. schmitti. É o primeiro relato da presença de WSSV em camarões L. schmitti e no siri C. danae silvestres. As principais espécies de camarões e siris dos ambientes de entorno das fazendas foram contaminadas pelo WSSV, constituindo-se em vetores potenciais do vírus.
Funcionalização de superfícies vítreas por plasma de SiCl4 para a retenção de compostos orgânicos
Authors: Assis O. B. G. , Paterno L. G.
Published: March 2012

Superfícies planas de vidro comercial, de composição básica soda-lime-silicato, foram tratadas em ambiente de plasma frio de O2 e SiCl4. Após a ação do plasma os vidros foram submetidos a uma seqüência de reações químicas (derivatização) em ambiente gasoso para a inserção de grupos funcionais reativos. Ao final do processo dois compostos orgânicos de interesse biotecnológico foram separadamente imobilizados: a enzima peroxidase e o polissacarídeo quitosana. Cada estágio do tratamento foi acompanhado por espectroscopia de fotoelétrons (XPS) identificando a variação dos principais elementos na superfície vítrea. O objetivo do presente estudo foi avaliar uma seqüência de funcionalização indicada para vidros e confirmar a imobilização dos compostos. Os resultados são de interesse para a confecção de biossensores e reatores de catálise tendo o vidro como suporte sólido.
Influência do Y2O3 na sinterização rápida de mulita comercial
Authors: Souto P. M. , Menezes R. R. , Kiminami R. H. G. A.
Published: March 2012

A mulita tem se tornado um material forte candidato para uso como cerâmica avançada e funcional. Nesse sentido, muito interesse tem sido devotado no estudo de aditivos de sinterização. Assim, este trabalho tem por objetivo analisar a influência do Y2O3 na queima rápida de mulita comercial. Pó de mulita comercial foi dopado com 0,5, 1,0 e 2,0% de Y2O3 prensado isostaticamente e submetida a ciclos de sinterização rápida a 1600 ºC. Foi determinada a densidade dos corpos sinterizados e executada sua análise por difração de raios X e microscopia eletrônica. A sinterização rápida da mulita gera corpos com baixa densidade, enquanto a adição de Y2O3 possibilita atingir elevadas densificações nos corpos mulíticos. O aumento do teor de Y2O3 não provoca alterações significativas na distribuição de tamanho de grão da mulita quando de sua sinterização rápida. Elevadas taxas de aquecimento permitem a obtenção de microestruturas com distribuições de tamanho de grão mais estreitas.
Ocorrência de uma nova bentonita brasileira nos basaltos intemperizados da formação Mosquito, bacia do Parnaíba, sul do Maranhão
Authors: Paz S. P. A. , Angélica R. S. , Neves R. F. , Neumann R. , Costa G. M. da
Published: March 2012

No município de Formosa da Serra Negra, sul do Maranhão, às margens da rodovia MA006, encontram-se afloramentos de basaltos intemperizados da Formação Mosquito, apresentando textura bastante argilosa e potencial de ser um material bentonítico. Neste trabalho, esse material que vem sendo considerado uma nova ocorrência de bentonita no Brasil e, batizado de Formosa, foi caracterizado por difração de raios X, fluorescência de raios X, microscopia eletrônica de varredura, espectroscopia Mössbauer e capacidade de troca catiônica, em amostra total e após separação granulométrica, e ainda, comparada com duas das principais bentonitas brasileiras, Chocolate e Bofe. Apesar das variações químicas e mineralógicas encontradas, muito comuns nesse tipo de argila, as semelhanças observadas convencem o promissor uso da argila Formosa como bentonita, uma vez que o ponto principal da caracterização está na presença dominante de montmorillonita e baixa concentração de outras fases minerais, mostrando que esse material apresenta mineralogia importante do ponto de vista tecnológico.
Atividade biológica e alcalóides indólicos do gênero Aspidosperma (Apocynaceae): uma revisão
Authors: Oliveira V.B. , Freitas M.S.M. , Mathias L. , Braz-Filho R. , Vieira I.J.C.
Published: March 2012

Embora sejam conhecidas principalmente como fonte de madeira nobre para aplicação na construção de móveis, as espécies do gênero Aspidosperma apresentam muitos estudos na área da fitoquímica e poucos estudos na área da farmacologia. As espécies do gênero Aspidosperma são largamente aplicadas por populares como potenciais agentes antimaláricos, no tratamento da leishmaniose, de inflamações do útero e ovário, como anticonceptiva, em diabetes e em problemas estomacais, contra câncer, febre e reumatismo. Do ponto de vista químico, a grande maioria das espécies constituintes do gênero já foi submetida a algum estudo de isolamento e identificação dos alcalóides indólicos presentes nas mais diversas partes das plantas. Já do ponto de vista farmacológico poucos testes foram realizados até então para justificar a grande aplicação das mesmas por populares e a importância dos alcalóides indólicos presentes nas representantes do gênero. Visando contribuir para um maior conhecimento sobre a importância da presença dos alcalóides indólicos no gênero Aspidosperma e sua relação com as atividades farmacológicas atribuídas ou testadas, é que apresentamos uma revisão das principais publicações envolvendo estudos químicos e biológicos do gênero Aspidosperma.
Performance and metabolic pattern of feedlot lambs using soyabean hulls associated to different non-protein nitrogen sources
Authors: Ziguer Evaneo Alcides , Roll Victor Fernando Büttow , Bermudes Rogério Fôlha , Montagner Paula , Pfeifer Luiz Francisco Machado , Del Pino Francisco Augusto Burkert , Corrêa Marcio Nunes , Dionello Nelson José Laurino
Published: March 2012

The aim of this study was to evaluate the metabolic profile of the use of soyabean hulls associated with two sources of non-protein nitrogen (NPN) on the finishing of feedlot lambs. Eighty crossbred Suffolk non-castrated lambs aging 69±6 days and weighing 23.11±1.78 kg were used. Lambs were randomly allocated into 4 experimental groups according to the NPN source: conventional urea (1%); protected urea; 1% protected urea + 0.5% conventional urea; and a control group, which did not receive urea supplementation. Blood samples were collected weekly to determine the plasma concentrations of urea, albumine, γ-glutamiltransferase (GGT), calcium and phosphorus. The control group had higher average daily gain and final weight than protected urea and protected urea + conventional urea groups; however, it did not differ from the conventional urea group. No differences between the groups were observed for dry matter intake, feed conversion or warm carcass yield and carcass finishing. Regarding the serum protein profile, the o group fed conventional urea had higher serum concentration of urea than that of protected + conventional urea. Urea supplementation did not improve the performance of feedlot lambs fed diets with high level of soybean hulls.
Aprendizagem situada, participação e legitimidade nas práticas de trabalho
Authors: Gudolle Lucas Socoloski , Antonello Claudia Simone , Flach Leonardo
Published: March 2012

O presente estudo tem por objetivo identificar e analisar o processo de aprendizagem situada a partir da participação e legitimidade nas práticas dos grupos de trabalho da Dublin Irish Pub. O arcabouço teórico envolve a aprendizagem situada, aprofundada junto com o estudo da participação periférica legitimada e diferentes níveis de participação nas práticas de trabalho dos grupos de trabalho. Com base no método qualitativo básico, a coleta de dados ocorreu por observação direta, diário de campo, entrevistas em profundidade. O período de observação de seis meses totalizou 32 idas a campo e oito entrevistas realizadas na empresa estudada. Assim, por meio da análise interpretativista, as informações da pesquisa permitem elucidar de que maneira a participação e legitimidade nas práticas de trabalho podem auxiliar na aprendizagem. Entre os resultados encontrados no estudo, destacam-se as formas de aprendizagem situada que surgiram em três grupos: garçons, barmen e cozinha. Descrevendo de forma analítica o engajamento e participação dos aprendizes nas práticas de trabalho e nas comunidades de prática, argumenta-se, com base neste trabalho, que esse processo de atuação nas comunidades de prática passa pela fase inicial de participação periférica legitimada, já que, a partir do engajamento e da atuação com os mais experientes, desenvolve-se a aprendizagem. Além disso, os ganhos de legitimidade e pertencimento são elementos relevantes no processo de aprendizagem, e pode-se identificar que o processo de aprendizagem situada não ocorre somente em comunidades de prática e que o pertencimento e a participação periférica legitimada são características a serem fomentadas nas organizações. A partir da negociação e renegociação de significados, pelo estabelecimento de relacionamentos sociais e comunidades de prática, cria-se um sistema por meio do qual os modos de ver, interpretar, compreender e praticar se constituem e são compartilhados.
Management of the Invasive Hill Raspberry (Rubus niveus) on Santiago Island, Galapagos: Eradication or Indefinite Control?
Authors: Renteria Jorge Luis , Gardener Mark R. , Panetta F. Dane , Crawley Mick J.
Published: March 2012

The eradication of an invasive plant species can provide substantial ecological and economic benefits by eliminating completely the negative effects of the weed and reducing the high cost of continuing control. A 5-yr program toward the eradication of hill raspberry (Rubus niveusThunb.) in Santiago Island is evaluated using delimitation and extirpation criteria, as well as assessment of the ecological community response to management techniques. Currently, hill raspberry is located in the humid zone of Santiago island. It is distributed over three main infestations, small patches, and many scattered individuals within an area of approximately 1,000 ha. New infestations are constantly being found; every year, new detections add an area of approximately 175 ha. Adult and juvenile individuals are still found, both beyond and within known infestations. Both plant and seed bank density of hill raspberry decreased over time where infestations were controlled. Species composition in the seed bank and existing vegetation were significantly different between areas under intensive control and adjacent uninvaded forest. After 5 yr of intensive management, delimitation of hill raspberry has not been achieved; new populations are found every year, increasing the infested area that requires management. Off-target effects on native species resulting from control efforts seem to be substantial. Although a vast increase in economic investment would allow intensive searching that might enable all individuals to be found and controlled, the resultant disturbance and off-targets effects could outweigh the conservation benefits of eradication.
Roads as Corridors for Invasive Plant Species: New Evidence from Smooth Bedstraw (Galium mollugo)
Authors: Meunier Geneviève , Lavoie Claude
Published: March 2012

Roads function as prime habitats and corridors for invasive plant species, and can contribute significantly to the spread and establishment of weeds inside protected areas. Smooth bedstraw (Galium mollugo) populations have recently expanded in the abandoned agricultural fields of Bic National Park (Quebec, Canada), and may represent a threat to the preservation of plant diversity and to the quality of visitor experience. The main objective of this study was to map the distribution of the species in the park and to delineate factors influencing the abundance of the plant in fallow fields. We hypothesized that road proximity was the main factor explaining the presence and abundance (frequency of recording) of smooth bedstraw in fields. Vegetation surveys were conducted in abandoned agricultural fields, and two logistic regression models were built to examine the relationship between the presence and abundance of smooth bedstraw and environmental and historical variables. Smooth bedstraw populations were also mapped along transportation corridors. The abundance of smooth bedstraw significantly increases within 125 m (410 ft) of a paved road. The recent proliferation of smooth bedstraw in Bic National Park is likely associated with the construction of road embankments during the paving of gravel roads. The paved road network has probably acted as a dispersal corridor for smooth bedstraw, while the abandoned agricultural fields located close to the paved roads provided suitable habitats facilitating population establishment over large areas. We recommended to the park's authorities to cease paving all remaining gravel roads in the park, not only to stop smooth bedstraw invasion, but also the spread of other invasive species of concern.
Long‐term data reveal patterns and controls on stream water chemistry in a forested stream: Walker Branch, Tennessee
Authors: Lutz Brian D. , Mulholland Patrick J. , Bernhardt Emily S.
Published: March 2012

We present 20 years of weekly stream water chemistry, hydrology, and climate data for the Walker Branch watershed in eastern Tennessee, USA. Since 1989, the watershed has experienced a ∼1.0°C increase in mean annual temperature, a ∼20% decline in precipitation, and a ∼30% increase in forest evapotranspiration rates. As a result, stream runoff has declined by ∼34%. We evaluate long‐term trends in stream water concentrations and fluxes for nine solutes and use wet deposition data to calculate approximate watershed input–output budgets.

Dissolved constituents were classified as geochemical solutes (Ca2+, Mg2+, and SO42−) or nutrients (NH4+, NO3−, soluble reactive phosphorus [SRP], total soluble nitrogen [TSN], total soluble phosphorus [TSP], and dissolved organic carbon [DOC]). Geochemical solutes are predominantly controlled by discharge, and the long‐term changes in catchment hydrology have led to significant trends in the concentrations and fluxes of these solutes. Further, the trends in geochemical solute concentrations indicate shifting soil flowpath contributions to streamflow generation through time, with deep groundwater having a greater proportional contribution in recent years.

Despite dramatic changes in watershed runoff, there were no trends in inorganic nutrient concentrations (NH4+, NO3−, and SRP). While most nutrients entering the watershed are retained, stream fluxes of nutrient solutes have declined significantly as a result of decreasing runoff. Nutrient concentrations in the stream exhibit large seasonality controlled by in‐stream biological uptake. Stream benthic communities are sensitive to hydrologic disturbance, and changes in the frequency or intensity of storm events through time can affect nutrient fluxes. Stream NO3− concentrations are also sensitive to drought, with concentrations decreasing (increasing) if conditions during the three years prior to the time of sampling were drier (wetter) than the long‐term mean. Future changes in the incidence of storm events, as well as the number and duration of droughts, have the potential to significantly alter watershed nutrient losses.

Our analysis indicates that changing climates can differentially affect watershed element cycles either through changes in biogeochemical process rates or through changes in catchment hydrology. Furthermore, climate change can include both long‐term trending in mean climate variables, as well as changes in the frequency and intensity of storms and droughts, with each of these types of change having distinct effects on the biological and geochemical processes governing different solutes.
Incorporating Into Reservoir Models How Nonreservoir Effects Impact Production Data
Authors: Hoffman B. Todd , Gopalan Karthik
Published: March 2012

There are a number of factors that can affect a well's production response that are not caused by the reservoir such as a fluid level in the wellbore, downhole pump inefficiencies, completion irregularities, a poor cement job, undetected formation damage and many others. The first part of this paper demonstrates the variability in the "measured" production data when these issues arise, and shows that the impact can lead to a well that produces significantly less than well that is influenced only by reservoir behavior.

Some of the non-reservoir effects (NRE) are known and included in reservoir models, but many are not known and not included in the models. When reservoir properties are modified to match data that is a function of non-reservoir behavior, we show that model predictions do not perform as well as when the NRE are incorporated. The next section of the paper presents ways to account for the NRE with a conventional reservoir simulator. Techniques are developed to automatically change the simulation models based on historical impact and frequency of the NRE.

The techniques were tested on a real field example with 25 years of historical production. We assumed that only the first 5 years were known and matched just that data, and then predicted the next 20 years using both a traditional model and one that included non-reservoir effects. The model with NRE has the same look as the real data and the prediction error was reduced from 47% to 8%.

In petroleum operations, there are other aspects besides the reservoir that impact the measured production data, and this work shows how to account for those effects. When included, models more accurately predict actual reservoir behavior, which should lead to better decision making about the reservoir.
Integrating Wellbore Hydraulics, Reservoir Properties, and Thermal Transient Analysis for SAGD Injector Well Completion Design with Multiple Outflow Control Devices: A Case Study
Authors: Medina Max , Wat Rex
Published: March 2012

The industry’s approach on SAGD injector well completion design is evolving in complexity by increasing the amount of steam-outflow distribution points along the horizontal wellbore. The main drivers in this evolution process are improved steam conformance and uniform chamber growth. Despite this trend, there are not many technical papers covering the criteria for selecting steam outflow locations, quantity and steam flow rate ratio at each distribution point.

This paper describes a case study of a SAGD injector well completion design comprised of two parallel strings and multiple outflow control devices placed along the well’s long string. We modeled the steam outflow profile into the reservoir with a commercial thermal wellbore simulator, which is coupled to a series of reservoir cells along the horizontal wellbore.

We based the preliminary completion design on the subsurface parameters that control steam flow into the reservoir (i.e. permeability, thickness, bitumen saturation, etc.). We derived these parameters from an up-to-date geological model based on core data, open-hole logs and cuttings analysis. At the end of the well’s circulation phase, we ran a series of temperature falloff logs from planned shut-in periods. We used fiber optic and thermocouple temperature data sets to perform thermal transient analysis, which allowed identifying the location of local/preliminary steam chambers and fingering phenomena. This diagnostic analysis generated a revision on the well’s preliminary completion design and steam outflow reservoir parameters.

We carried out a final design using real SAGD performance data obtained from thermal transient analysis. The design objective was to negate the uncharacteristic steam chamber growth features, developed during the circulation phase, to promote uniform development along the wellbore. This paper provides a methodology and criteria for SAGD injector completion design that can be broadly applied across the industry, integrating wellbore hydraulics, reservoir properties and thermal transient analysis into the design process.
Production Optimization and Forecasting of Shale Gas wells Using Simulation Models and Decline Curve Analysis
Authors: Ikewun Peter , Ahmadi Mohabbat
Published: March 2012

This paper involves the use of simulation models and the decline curve analysis (DCA) as a production optimization and forecasting tools. Production data from three neighboring counties (with high, medium and low cumulative gas productions) of the Eagle Ford shale, an analogue to the Shublik shale of Alaska, was analyzed using the DCA to correlate production performance with completion (horizontal leg/stages of fracture) and length of horizontal leg. We built and run generic simulation models using realistic range of properties. Simulation results provided a better understanding of interplay between static properties and dynamic behavior. The simulation results highlight how and when the key influential elements such as gas desorption, fracture closure with depletion, varying medium and fracture properties, different hydraulic fracture configuration, and various natural fracture networks will affect the well production.

The use of the method proposed in this paper would result in better and more reliable production forecast at the Eagle Ford and other young producing shale reservoirs possessing short production history. The modeling of these complex reservoir geometry and fracture networks would give an extensive understanding of the flow mechanics in shale reservoirs and identify the key parameters affecting production performance. It would also serve as a screening tool for fracturing/re-fracturing operations and give optimal hydraulic fracture configuration for various mediums and natural fracture networks.

Results from the decline curve analysis of 24 producing wells with production histories of 9-57 months showed an increase in reserves with more fracture stages but not at all instances which makes the use of simulation models very valuable and necessary in obtaining further results and explanations. DCA generated different forecast depending on which part of data were used. This clearly indicated the need for running simulations. Simulation runs can generate more reliable production forecast of which the decline part can be used to evaluate the capability of DCA to reproduce the production profiles. The results from simulation can provide a clear picture of the role of key influencing parameters from both reservoir and well stimulation/completion on well production performance.

The results from this study will provide answer to the following questions: How long the production history needs to be for DCA to generate reliable forecasts?
 What are the key reservoir and completion elements that strongly affect the production? And what parameters control the choice of well spacing?
The Vedder Lease, Section 9, Mt. Poso Field, California: A Unique Case History
Authors: Evans Barry L.
Published: March 2012

Oil production from the Vedder lease began in 1926 with the discovery of the Mount Poso oil field. Oil production has continued for 86 years and development is continuing. The Vedder lease is in the heart of the Main Area of the field. Following primary production, steamflooding the three Vedder sands resulted in very high recovery factors. The Vedder sands had strong aquifers and each sand required a specific design for steamflooding. Later development has been in the Pyramid Hills sands. This development has featured vertical and horizontal drilling and hydraulic fracturing. It is believed that the Pyramid Hills sands have waterflood potential and could further increase the oil reserves and economic life of the field.

The field was sold by a major oil company in March 1999. Operations have been conducted by three other oil companies since 1999. The field is an example of how smaller oil companies can use new technologies to increase oil production and oil reserves resulting in extending the life of an oil field. The implementation of all these processes has required the use several legal agreements. Over the 86 years the Vedder lease has involved three generations of the Vedder family.
Analytical Study of Effects of Flow Rate, Capillarity and Gravity on CO2/Brine Multiphase Flow System in Horizontal Corefloods
Authors: Kuo Chia-Wei , Benson Sally M.
Published: March 2012

This paper presents an approximate semi-analytical solution for predicting the average steady-state saturation during multiphase core flood experiments over a wide range of capillary and gravity numbers. Recently, the influences of flow rate, gravity, and sub-core heterogeneity on the brine displacement efficiency have been studied using the 3-D simulator TOUGH2 (Kuo et al. 2010). These studies have demonstrated that the average saturation depends on the capillary and gravity numbers in a predictable way.

The purpose of this paper is to provide a simple approximate semi-analytical solution for predicting the average saturation during core flood experiments, thus avoiding the need for 3-D simulations. A two dimensional analysis of the governing equations for the CO2/brine multiphase flow system at steady-state is used to develop the approximate semi-analytical solution. We have developed a new criterion to identify the viscous-dominated regime at core scale. Variations of interfacial tension, core permeability, length of the core, and the effects of buoyancy, capillary and viscous forces are all accounted in the theoretical solutions. We have also shown that three dimensionless numbers (NB, Ngv, Rl) and two critical gravity numbers (Ngv, c1, Ngv, c2) are required to properly capture the balance of viscous, gravity, and capillary forces. There is good agreement of the average saturations between the 3-D simulations and the model. This new model can be used to design and interpret multiphase flow core-flood experiments.
Real-Time Downhole Monitoring of Electrical Submersible Pumps Rated to 250°C Using Fiber Optic Sensors: Case Study and Data Value in the Leismer SAGD Project
Authors: Medina Max , Torres Carlos , Sanchez Julio , Boida Lindsey , Leon Alfredo , Jones Jason , Yicon Carlos
Published: March 2012

Leismer is the first Statoil operated steam-assisted gravity drainage (SAGD) project in the Athabasca region of Alberta, Canada. Electrical submersible pumping systems (ESPs) are the standard artificial lift method for this project. A field trial was planned for newly developed ESPs rated to 250°C. The increased temperature rating allows operating SAGD chambers at higher pressures, thus providing more operational flexibility for increasing recovery and dealing with common exploitation problems. The field trial required reliable and comprehensive down-hole monitoring, so that thorough ESP performance analysis could be performed under real field conditions.

Given the extreme conditions at which ESP systems operate in SAGD, fiber optic pressure and temperature sensors were selected for real-time down-hole monitoring. These sensors were placed at the pump intake, inside the motor and at the discharge. The fiber optic gauges’ performance is comparable to standard SAGD measurement devices, but without some of the disadvantages.

The sensing system configuration, ESP interface and installation will be described. This paper will also present the value of real-time ESP monitoring. The pump operation is controlled by continuously history matching performance with well performance software and adjusting parameters to changing down-hole conditions. This ensures the ESPs are run near the best efficiency point. Pump intake sub-cool is controlled to minimize steam flashing occurrence. ESP motor temperature is monitored to boost reliability and run time. Finally, discharge pressure measurement has been used for history matching multiphase flow correlations. This improves ESP performance calculation accuracy in the field’s other wells.

Integrating ESP advances with fiber optic measurement has allowed effective local technology qualification under real operating conditions. This project has provided abundant information and knowledge for field-wide production optimization.
Combining Absorption and AVO Seismic Attributes Using Neural Networks to High-Grade Gas Prospects
Authors: Rahimi Zeynal A. , Aminzadeh F. , Clifford A.
Published: March 2012

A seismic attribute is a transformation of the original seismic data that can help determine the rock type and fluid characters. AVO attribute analysis is a proven method for confirming seismic amplitude anomalies associated with gas anomalies. AVO analysis examines the intensity of seismic reflections at varying source-receiver distances (offset). The major risk with AVO analysis is whether seismic amplitude anomalies represent commercial or non-commercial gas accumulations. Combining AVO and absorption attributes using ANN reduces this risk. Further risk reduction is accomplished thorough investigation of the different types of absorption attributes and enhancing the ANN training with petrophysical information derived from well logs. We demonstrate that the high frequency content of the seismic response attenuates more as it propagates through gas-bearing reservoirs and, unlike AVO, the absorption attribute is impacted by the amount of gas saturation. Furthermore, we demonstrate how the correlation between shallow gas and shallow seismic amplitudes improves as we include different types of well logs with proper calibration. The ANN, trained by the suite of logs and different frequency-related attributes, enhances the ability to detect undeveloped pockets of shallow gas. Gas has a very marked effect on both density and neutron logs, resulting in lower bulk density and lower apparent neutron porosity. Therefore, combining neutron and density logs and training neural networks based on the well logs with AVO and AQF attributes, instead of just training based on attributes alone, increases the certainty of suspected gas pockets. The real power comes from being able to tie absorption and AVO anomalies with other frequency attributes.
Acidizing Optimization: Monterey Shale, California
Authors: Trehan Rakesh , Jones Norman , Haney James
Published: March 2012

Hydrofluoric (HF) acidizing in the Monterey shale has had a long history of success, dating back to a case study performed in 1999 (Rowe et al. 2004). A proper acid-design program is critical to the success of these types of treatments. However, proper placement technique carries the same importance as the acid design. This paper will review a placement technique that not only provided proper placement but also reduced placement time significantly.

Monterey shale intervals commonly reach 1,500 to 2,000 ft in vertical height. To further complicate downhole work, intervals are not homogeneous; there are differences in natural fractures, permeability, and porosity. The goal of matrixacidizing treatments is to place the acid below fracture pressures. Formation differences, including degree of damage, can limit injection rates and increase the pump time necessary to place the acid. Physical well conditions, such as the cement bond, create other challenges to overcome. Placement time for these acid treatments often takes several days to complete and can require multiple service providers, such as production rigs, downhole tools, remedial cement work, and coiled tubing (CT) units. With consideration to these issues, several questions arise, such as how can the entire interval be successfully acidized, the number of required services reduced, and placement time decreased.

Using the new placement technique, the entire planned completion interval can be perforated in a rigless manner, acid equipment can be moved in that is capable of producing sufficient injection rates to exceed the formation’s ability to accept fluid below the fracture gradient, and real-time downhole monitoring equipment is installed to provide the operator and service provider adequate data to make decisions and adjust as necessary while pumping.
Impact of California's Greenhouse Gas Law on the Upstream Oil & Gas Industry
Authors: Winslow Don
Published: March 2012

The California legislature passed the "Global Warming Solution Act?? (Assembly Bill 32) in 2006. Although the AB32 bill was only 12 pages long, it spawned numerous initiatives that will create the first comprehensive multi-sector greenhouse gas (GHG) reduction program in the US, and arguably, the world. This effort has engaged hundreds of people within the California state government and generated thousands of pages of detailed rules and studies. The upstream oil and gas production industry in California will be directly impacted by multiple initiatives that have arisen due to AB32 including: (1) Cap-and-Trade; (2) mandatory GHG reporting; and indirectly through (3) additional environmental factors to be considered in the context of CEQA permitting of new projects.

Note that the greenhouse gas (GHG) regulations and programs in California are still very much in flux and thus, statements in this paper could become inaccurate. Court cases have been filed in 2010 and 2011 which challenge specific programs associated with AB32. One such example was a recent court decision related to the implementation of the low carbon fuel standard. Finally, this paper is not meant to be a comprehensive treatise on the specific rules of AB32. Instead it is intended to be a short introduction to the various California-sponsored GHG initiatives that impact the oil and gas sector. CARB has generated hundreds of pages of documentation for individual components of the AB32 program such as Cap-and-Trade or reporting. Thus, this paper is intended as a summary of the programs and the regulations for technical personnel in the upstream sector. Finally, this paper does not purport to represent the views of Chevron Corp. Any errors or opinions are solely those of the author.
Saving phosphorus removal at the Henderson NV plant
Authors: Barnard J. , Houweling D. , Analla H. , Steichen M.
Published: March 2012

While the mechanism of biological phosphorus removal (BPR) and the need for volatile fatty acids (VFA) have been well researched and documented to the point where it is now possible to design a plant with a very reliable phosphorus removal process using formal flow sheets, BPR is still observed in a number of plants that have no designated anaerobic zone, which was considered essential for phosphorus removal. Some examples are given in this paper. A theory is proposed and then applied to solve problems with a shortage of VFA in the influent of the Henderson NV plant. Mixed liquor was fermented in the anaerobic zone, which resulted in phosphorus removal to very low levels. This paper will discuss some of the background, and some case histories and applications, and present a simple postulation as to the mechanism and efforts at modelling the results.