bluuebunny/crossref_metadata_2025 huggingface dataset:
Características acústicas da oclusiva glotal associada à sequência de Pierre Robin: estudo de caso
Authors: Marino Viviane Cristina de Castro , Berti Larissa Cristina , Lima-Gregio Aveliny Mantovan
Published: March 2012

A fissura de palato, em associação à Sequência de Pierre Robin, pode favorecer o desenvolvimento de produções atípicas (compensatórias), na fala da criança, como é o caso da oclusiva glotal (golpe de glote) comumente observada em substituição aos sons oclusivos (vozeados ou não). No presente estudo, foi realizada a análise dos parâmetros fonético-acústicos da oclusiva glotal produzidas em /k/ e /g/ por uma criança do gênero feminino, com 5 anos, que apresentava fissura de palato reparada, associada à Sequência de Pierre Robin. Para isso, foram selecionadas seis palavras em que a oclusiva velar encontrava-se na posição inicial da palavra e combinada com as vogais /a/, /i/ e /u/ na posição acentuada. Foi ainda realizado julgamento perceptivo-auditivo por três fonoaudiólogos, que apresentou concordância quanto à presença da oclusiva glotal de 100% para ambas as relações (intra e inter-juízes). Na inspeção dos dados via espectrograma foi observada variabilidade dos parâmetros espectrais (burst e transição formântica) e essas variações também puderam ser computadas considerando as vogais separadamente. A análise estatística revelou diferença estatisticamente significante entre as duas consoantes velares (/k/ e /g/) nos parâmetros espectral (burst), temporal (VOT e duração relativa da oclusiva na palavra) e os relativos às características acústicas das vogais adjacentes às oclusivas (período estacionário de F3). Por fim, as características acústicas da oclusiva glotal sugeriram que a criança pode ter utilizado de estratégias para marcar contrastes fônicos na língua, ainda que os mesmos não tenham magnitude suficiente para serem resgatados auditivamente pelo ouvinte.
Qualidade de vida dos professores da área de ciências em escola pública no Rio Grande do Sul
Authors: Brum Liliani Mathias , Azambuja Cati Reckelberg , Rezer João Felipe Peres , Temp Daiana Sonego , Carpilovsky Cristiane Köhler , Lopes Luis Felipe , Schetinger Maria Rosa Chitolina
Published: March 2012

A investigação da qualidade de vida dos professores de ciências e a busca por melhorias que promovam um melhor desempenho desses profissionais no cotidiano das escolas podem ser uma forma de reduzir as desigualdades na educação no Brasil e favorecer o crescimento dos professores em nível educacional e social. Este estudo teve o objetivo de analisar indicadores físicos e mentais de qualidade de vida dos professores de ciências de uma escola pública localizada no interior do Rio Grande do Sul. Foram avaliadas informações acerca das características demográficas, econômicas, ocupacionais, atividades domésticas, esforços físicos, saúde física, saúde mental e os diagnósticos médicos mais referidos pelos professores desde o início do trabalho como docente. Como resultados, encontraram-se diversas queixas em relação à saúde e à qualidade de vida dos professores estudados, como nervosismo, rouquidão, dor nas costas, braços e pernas, além de formigamento e inchaço nas pernas. Conclui-se que o conhecimento dessas evidências pode contribuir para a construção de medidas para a reorganização da sistemática de trabalho e influenciar diretamente na qualidade de vida dos professores, gerando melhor desempenho na atividade de educar.
Um novo olhar sobre a elaboração de materiais didáticos para educação em saúde
Authors: Rossi Samuel Quinaud , Belo Vinícius Silva , Nascimento Bruno Warlley Leandro , Silva Jacqueline da , Fernandes Priscila Correia , Silva Eduardo Sérgio da
Published: March 2012

O presente artigo tem como objetivo lançar um olhar crítico sobre o processo de elaboração de um conjunto de materiais didáticos em Educação em Saúde, produzido a partir do ano de 2007 na Universidade Federal de São João del-Rei, para uso em um programa que visava o combate a parasitoses intestinais. Os materiais foram analisados de forma a se avaliar as potencialidades e as deficiências encontradas. Como resultado, obtevese a necessária reelaboração deles, com o objetivo de que sejam utilizados como meios educativos que respeitem identidades e contribuam para a construção de saberes em relação à saúde. Espera-se que as propostas de reelaboração e correção, juntamente com as características positivas analisadas, possam colaborar com a produção de novos materiais e contribuir para a melhoria da oferta de produtos que medeiem o processo de construção de conhecimentos na área da saúde.
Potential drug delivery system: study of the association of a model nitroimidazole drug with aggregates of amphiphilic polymers on aqueous solution
Authors: Salamanca Mejia Constain Hugo , Urbano Bruno Felipe , Olea Carrasco Andres Floreal
Published: March 2012

This study evaluated the association of N-hexyl-2-methyl-4-nitroimidazol, a model drug, to aggregates formed by anionic polyelectrolytes on aqueous solution. The alternating copolymers of maleic anhydride and N-vinyl-2-pyrrolidone were synthesized and then modified by reaction of the anhydride groups with aliphatic amines and alcohols of varying length of the alkyl chain. The partition of the model drug between water and the hydrophobic microdomains provided by the copolymers was studied using the pseudo-phase model to determinate the distribution coefficient K S, and the standard free energy of transfer ∆µ°t. The results indicate that all copolymers assessed are potential pharmaceutical reservoirs of the model drug. Nevertheless, the solubility of N-hexyl-2-methyl-4-nitroimidazol on the polymeric solutions is independent from the length of the alkyl chain of the copolymer.
Application of multivariate techniques in the evaluation of melt granulation products
Authors: Ochoa Andrade Ana Teresa
Published: March 2012

In this work, principal component analysis and cluster analysis were applied as helping tools to extract useful information in the development of formulations and manufacturing processes of melt granulates. Two melt granulation processes that differ in the shear stress applied to the solid bed during melting step were designed. These processes employ equipment frequently used in the local pharmaceutical industry. The selected binders include both hydrophilic and hydrophobic excipients, which were used alone or in binary mixtures. Granulates were characterized regarding their physicomechanical properties, including their compaction behavior. The resulting tablets were also evaluated. The selected multivariate statistical methods proved to be useful in facilitating the interpretation of the collected data and the study of the properties of granulates and tablets, as well as the selection of more efficient production processes.
Determination of parabens in sweeteners by capillary electrochromatography
Authors: Bottoli Carla Beatriz Grespan , Gutiérrez-Ponce María de Jesús Santa , Aguiar Valeska Soares , Aquino Walkyria Moraes de
Published: March 2012

Parabens, common food preservatives, were analysed by capillary electrochromatography, using a commercial C18 silica (3 µm, 40 cm × 100 µm i. d.) capillary column as separation phase. In order to optimise the separation of these preservatives, the effects of mobile phase composition on the separation were evaluated, as well as the applied voltage and injection conditions. The retention behavior of these analytes was strongly influenced by the level of acetonitrile in the mobile phase. An optimal separation of the parabens was obtained within 18.5 minutes with a pH 8.0 mobile phase composed of 50:50 v/v tris(hydroxymethyl)aminomethane buffer and acetonitrile. The method was successfully applied to the quantitative analysis of paraben preservatives in sweetener samples with direct injection.
Evaluation of adherence to treatment by patients seen in a psychosocial care center in northeastern Brazil
Authors: Souza Thaís Teles , Silva Wellington Barros , Onofre Alexandre Sherlley Casimiro , Quintans Jullyana de Souza Siqueira , Onofre Fabiana Botelho de Miranda , Quintans-Júnior Lucindo José
Published: March 2012

In the treatment of mental disorders, nonadherence to medication, the main cause of psychiatric morbidity, is observed in about 50% of the cases and is responsible for numerous losses. This study evaluated adherence to drug treatment by patients seen in a Psychosocial Care Center (CAPS) in northeastern Brazil. Adherence to treatment was evaluated using the Haynes-Sackett and Morisky-Green-Levine tests. All patients registered in the CAPS were included in the study (n= 101). Only 11.88% of the patients adhered to drug treatment. The main reasons not to use medication were: oblivion (68.83%), feeling unwell after taking the medication (54.22%), not having money to buy the medication (43.83%), not finding the medication in the public health service (39.94%) and fear of harm that might be caused by the drug (28.90%). Furthermore, 85.1% of the patients did not know their diseases, 88.1% did not know their treatment, 86.4% did not feel good when they took their medication, and 88.1% took their medication incorrectly. The results revealed that the lack of information about diseases and drugs used, the nuisance posed by drug therapy and the low access to medications reduce adherence to treatment and, consequently, treatment effectiveness.
Memory retrieval improvement by Heteropterys aphrodisiaca in aging rats
Authors: Galvão Suzana Maria Pereira , Mendes Fúlvio Rieli , Oliveira Maria Gabriela Menezes de , Mattei Rita , Mello João Carlos Palazzo de , Roman Júnior Walter Antonio , Carlini Elisaldo de Araújo
Published: March 2012

Few data exists about the pharmacological properties of Heteropterys aphrodisiaca O. Mach. (Malpighiaceae), which is native to the scrubland regions of Brazil. The present study investigated the effects of oral treatment with H. aphrodisiaca extract (BST0298) on the learning and memory of young (3-6 months) and aged (21-23 months) rats, and compared the in vitro antioxidant activity of three lots collected in different years. An improvement in the number of sessions to learn the task was observed in the left/right discrimination test in aged rats treated for 45 days with 25 mg/kg (7.0 ± 0.5; p=0.005) or 50 mg/kg (7.6 ± 0.6; p=0.012) compared with control old rats (11.0 ± 1.6). On the other hand, pre-treatment did not improve the performance of scopolamine-treated mice in the passive avoidance test. The in vitro malondialdehyde test showed that all three different extracts presented similar antioxidant activity. The flavonoids astilbin, isoastilbin and neoastilbin were isolated from the extract and may contribute to the biological activity. These results suggest that repeated treatment with H. aphrodisiaca improves learning and memory, probably by a non-muscarinic mechanism.
Alginate/hydrophobic HPMC (60M) particulate systems: new matrix for site-specific and controlled drug delivery
Authors: Ghosal Kajal , Ray Sarbani Dey
Published: March 2012

This study aimed to obtain site-specific and controlled drug release particulate systems. Some particulates were prepared using different concentrations of sodium alginate (Na-Alg) alone and others were formulated using different proportions of Na-Alg with hydroxypropyl methylcellulose (HPMC) stearoxy ether (60M viscosity grade), a hydrophobic form of conventional HPMC, using diclofenac potassium (DP) by ion-exchange methods. Beads were characterized by encapsulation efficiency, release profile, swelling, and erosion rate. The suitability of common empirical (zero-order, first-order and Higuchi) and semi-empirical (Ritger-Peppas and Peppas-Sahlin) models was studied to describe the drug release profile. The Weibull model was also studied. Models were tested by non-linear least-square curve fitting. A general purpose mathematical software (MATLAB) was used as an analysis tool. In addition, instead of the widely used linear fitting of log-transformed data, direct fitting was used to avoid any sort of truncation or transformation errors. The release kinetics of the beads indicated a purely relaxation-controlled delivery, referred to as case II transport. Weibull distribution showed a close fit. The release of DP from Na-Alg particulates was complete in 5-6 hours, whereas from Na-Alg hydrophobic HPMC particulate systems, release was sustained up to 10 hours. Hydrophobic HPMC with Na-Alg is an excellent matrix to formulate site-specific and controlled drug release particulate systems.
Anti-inflammatory and toxicity studies of atranorin extracted from Cladina kalbii Ahti in rodents
Authors: Melo Marcelia Garcez Dória de , Araújo Adriano Antunes de Souza , Serafini Mairim Russo , Carvalho Larissa Feitosa , Bezerra Marília Santos , Ramos Cledison Santos , Bonjardim Leonardo Rigoldi , Albuquerque-Júnior Ricardo Luiz Cavalcanti , Lima Julianeli Tolentino , Siqueira Rosana Souza , Fortes Vanessa Silveira , Fonseca Maria José Vieira , Quintans-Júnior Lucindo José
Published: March 2012

Atranorin (ATR) is the main compound from the lichen Cladina kalbii Ahti, which grows in the arid regions of northeastern Brazil. This study was conducted to evaluate the anti-inflammatory and toxicological properties of ATR. To evaluate anti-inflammatory properties, paw edema was induced by injecting 0.1 mL of carrageenan into the subplantar region of the right hind paw of rats, and leukocyte migration was induced by injection of 500 µL of carrageenan into the peritoneal cavity of mice. In addition, we determined ATR cytotoxicity in L929 cells by MTT assay and acute (5 g/kg-single dose) and subchronic (50 mg/kg-30 days) toxicity tests in Wistar rats. The results showed that ATR (100 mg/kg and 200 mg/kg) exhibited significant anti-inflammatory activity (paw edema and leukocyte migration). In the acute toxicity test, the animals showed hypoactivity and lethargy during the initial period (first 6 hours) and increase in total protein, total and indirect bilirubin, and alkaline phosphatase after 14 days in ATR-treated male rats. The subchronic toxicity test revealed increases in total protein, globulin, gamma-glutamyl transferase, alkaline phosphatase, and total and direct bilirubin in ATR-treated female rats. Histological analysis revealed no changes in the architecture and morphology of the organs. These results suggest that ATR has significant anti-inflammatory activity, with no significant acute and subchronic toxicity or cytotoxicity.
Efeitos imediatos do exercício vocal sopro e som agudo
Authors: Maia Maria Emilia Oliveira , Maia Mariana Oliveira , Gama Ana Cristina Côrtes , Behlau Mara
Published: March 2012

OBJETIVO: Investigar os efeitos imediatos do exercício vocal sopro e som agudo. MÉTODOS: Trata-se de estudo tipo observacional comparativo. Participaram 46 mulheres com idades entre 25 a 45 anos que foram divididas em dois grupos: 23 com queixa vocal (GQ) e 23 sem queixa vocal (GSQ). Foram realizadas a avaliação perceptivo-auditiva da qualidade vocal, análise acústica, videolaringoestroboscopia e autoavaliação da voz antes e após a execução do exercício sopro e som agudo em dez repetições. A avaliação perceptivo-auditiva e das imagens da configuração laríngea foram realizadas por três fonoaudiólogas especialistas em voz, que deveriam analisar dois trechos de cada sujeito, sem a identificação do momento do registro, assinalando o melhor trecho. Os parâmetros acústicos avaliados foram frequência fundamental, jitter e shimmer na vogal sustentada e frequência fundamental na fala encadeada. Na autoavaliação vocal, todos os participantes deveriam responder à pergunta: "Como você avalia a sua voz após a realização do exercício?". RESULTADOS: Na avaliação perceptivo-auditiva, ambos os grupos apresentaram melhor qualidade vocal no pós-exercício. Quanto à avaliação acústica, após o exercício houve diminuição dos valores shimmer, em ambos os grupos e nas medidas de jitter no GSQ. Observou-se aumento da frequência fundamental no GQ na vogal sustentada. A avaliação videolaringoestroboscópica mostrou melhor coaptação glótica e menor envolvimento do vestíbulo em ambos os grupos pós-exercício. A autoavaliação vocal indicou melhora na emissão da voz no GQ. CONCLUSÃO: O exercício vocal sopro e som agudo produz efeitos imediatos positivos nas avaliações perceptivo-auditiva, acústica, laríngea e na autoavaliação vocal.
Intervenção fonoaudiológica em grupo a cantores populares: estudo prospectivo controlado
Authors: Goulart Bárbara Niegia Garcia de , Rocha Jaqueline Garcia da , Chiari Brasilia Maria
Published: March 2012

OBJETIVO: Verificar os benefícios de um programa de aperfeiçoamento vocal em grupo a cantores populares. MÉTODOS: Trata-se de estudo de intervenção, quase experimental, realizado com 37 cantores populares de ambos os gêneros, com idades entre 18 e 40 anos e qualidade vocal adaptada. Os participantes foram divididos em dois grupos: Intervenção (GI) e Controle (GC). O GI contou com 21 indivíduos que receberam orientações sobre anátomo-fisiologia do aparelho fonador, cuidados de higiene vocal e realização de exercícios vocais, em um total de sete encontros. O GC contou 16 participantes, que mantiveram suas atividades normais durante o período de realização da pesquisa e não receberam as orientações sobre o aperfeiçoamento vocal. Nos períodos pré e pós-intervenção todos os participantes responderam a um questionário sobre hábitos e demandas relacionadas à voz e foram avaliados em relação a: ressonância, articulação, projeção, pitch, loudness, tempo máximo de fonação e relação s/z. RESULTADOS: O trabalho de aperfeiçoamento vocal mostrou-se positivo na percepção dos cantores, que referiram melhora em suas vozes. Os tempos máximos de fonação e a relação s/z não apresentaram diferença entre os grupos (p=0,57). Não houve modificação dos comportamentos potencialmente nocivos à saúde vocal (p=0,24) em até 60 dias após a intervenção. Não foi observada diminuição considerável das queixas vocais (p=0,1), ainda que a porcentagem de redução de queixas do GI (22,2%) tenha sido maior que a do GC (11,1%). CONCLUSÃO: A intervenção fonoaudiológica em grupo a cantores populares é positiva no que se refere à percepção do indivíduo sobre sua produção vocal, ainda que estes apresentem voz adaptada desde o início do processo.
Processamento temporal de crianças com transtorno fonológico submetidas ao treino auditivo: estudo piloto
Authors: Vilela Nadia , Wertzner Haydée Fiszbein , Sanches Seisse Gabriela Gandolfi , Neves-Lobo Ivone Ferreira , Carvallo Renata Mota Mamede
Published: March 2012

OBJETIVO: Comparar o desempenho em processamento temporal de crianças com transtorno fonológico submetidos a treino auditivo formal e informal. MÉTODOS: Quinze indivíduos com transtorno fonológico (limiares tonais ≤20 dBNA de 0,50 a 4 kHz e idades entre 7 anos e 10 anos e 11 meses) foram avaliados e divididos em três grupos: Grupo Controle - composto por cinco indivíduos (média de idade de 9,1 anos) sem transtorno do processamento auditivo, que passaram por duas avaliações do processamento auditivo (central) com intervalo de seis a oito semanas, sem receber qualquer intervenção; Grupo Treino Formal - composto por cinco indivíduos (média de idade de 8,3 anos), com transtorno do processamento auditivo, submetidos a oito sessões de treino formal; e Grupo Treino Informal - composto por cinco indivíduos (média de idade de 8,1 anos) com transtorno do processamento auditivo, submetidos a oito sessões de treino informal. RESULTADOS: Após oito sessões, o grupo treino formal apresentou melhora de 8% e o grupo treino informal de 22,5% no que se refere ao teste padrão temporal de frequência. Para o teste padrão temporal de duração, o grupo treino formal melhorou 12,9% e o grupo treino informal 18,7%. No desempenho nos testes padrão de frequência e padrão de duração, não houve diferença estatística entre as médias obtidas pelos dois grupos após a intervenção. CONCLUSÃO: Embora os resultados não tenham apresentado significância estatística, o estudo piloto apresentado sugere que ambos os treinos, formal e informal, proporcionam melhora das habilidades de processamento temporal em crianças com transtorno fonológico e do processamento auditivo.
Estimulabilidade: medida auxiliar na identificação de dificuldade na produção dos sons
Authors: Castro Márcia Mathias de , Wertzner Haydée Fiszbein
Published: March 2012

OBJETIVO: Analisar a efetividade da estimulabilidade como prova complementar ao diagnóstico do transtorno fonológico (TF) e descrever o desempenho de crianças com ausência de sons no inventário fonético quanto a sons ausentes estimuláveis, gravidade, gênero, idade e ocorrência de diferentes processos fonológicos. MÉTODOS: Participaram 130 crianças de ambos os gêneros, entre 5 anos e 10 anos e 10 meses de idade, distribuídas em dois grupos: Grupo Pesquisa (GP), composto por 55 crianças com TF; e Grupo Controle (GC), composto por 75 crianças sem alterações fonoaudiológicas. A partir da aplicação da prova de Fonologia, foi calculada a gravidade do TF por meio do Percentual de Consoantes Corretas-Revisada (PCC-R) e verificado o inventário fonético. Para cada som ausente do inventário foi aplicada a estimulabilidade em imitação de palavras. O GP foi dividido em GP1 (27 crianças que apresentaram sons ausentes) e GP2 (28 crianças com inventário completo). RESULTADOS: Nenhuma criança do GC apresentou som ausente no inventário e no GP1 49% apresentaram sons ausentes. Houve ausência da maioria dos sons da língua. As médias do PCC-R foram menores no GP1, indicando maior gravidade. No GP1, 22 crianças foram estimuláveis e cinco não o foram a qualquer som. Houve associação entre os processos fonológicos mais ocorrentes no TF e a necessidade de avaliação da estimulabilidade, o que indica que a dificuldade em produzir os sons ausentes reflete dificuldade de representação fonológica. A estimulabilidade sofre influência da idade, mas não do gênero. CONCLUSÃO: A prova de estimulabilidade é efetiva para identificar dentre crianças com sons ausentes do inventário, aquelas que são estimuláveis. Tais crianças com TF, que apresentam sons ausentes do inventário, são mais graves uma vez que os valores do PCC-R são mais baixos. As crianças com sons ausentes são estimuláveis em sua maioria, e podem não ser estimuláveis para sons com estrutura silábica ou gesto articulatório complexos. A dificuldade em produzir os sons ausentes reflete dificuldade de representação fonológica. A produção motora da fala demonstrou receber influência da maturação de forma semelhante entre meninos e meninas.
Comparação dos instrumentos Childhood Autism Rating Scale e Autism Behavior Checklist na identificação e caracterização de indivíduos com distúrbios do espectro autístico
Authors: Santos Thaís Helena Ferreira , Barbosa Milene Rossi Pereira , Pimentel Ana Gabriela Lopes , Lacerda Camila Andrioli , Balestro Juliana Izidro , Amato Cibelle Albuquerque de la Higuera , Fernandes Fernanda Dreux Miranda
Published: March 2012

OBJETIVO: Comparar as respostas dos instrumentos Childhood Autism Rating Scale e Autism Behavior Checklist na identificação e caracterização de indivíduos com Distúrbios do Espectro Autístico. MÉTODOS: Participaram 28 indivíduos que estavam em atendimento fonoaudiológico e possuíam diagnósticos inseridos no Espectro do Autismo. Todos foram avaliados por meio dos instrumentos Autism Behavior Checklist e Childhood Autism Rating Scale a partir de informações obtidas, respectivamente, com pais e terapeutas. Os dados foram analisados estatisticamente em relação à concordância das respostas obtidas. Foram considerados concordantes os resultados de alta ou moderada probabilidade para autismo no Autism Behavior Checklist e com autismo leve-moderado ou grave na Childhood Autism Rating Scale, e respostas de baixa probabilidade no Autism Behavior Checklist e sem autismo na Childhood Autism Rating Scale. RESULTADOS: Houve concordância na maior parte das respostas obtidas. Casos em que houve discordância entre os resultados obtidos a partir dos protocolos corroboram dados da literatura, evidenciando que os instrumentos podem não ser suficientes, quando aplicados isoladamente para a definição do diagnóstico. CONCLUSÃO: Enquanto a Childhood Autism Rating Scale pode não diagnosticar crianças efetivamente autistas, o Autism Behavior Checklist pode incluir como autistas, crianças com outros distúrbios. Portanto, recomenda-se o uso complementar dos dois instrumentos.
Identification of Secondary & Tertiary Precipitants of Sandstone Acidization Allows Minimization of Formation Damage: A Laboratory Study
Authors: Kumar Ajay , Yadav N. , Rao YRL , Singhal C. P. , Kumar Ajit
Published: March 2012

The Nandasan field discovered in 1969 is a multi-layered reservoir in western part of India and producing oil & gas with little problem as it is having good porosity and permeability. Deeper multi layered mehsana formation comprises of 45% silicon, 9%aluminium, 18%iron, 0.23%calcium, 0.47%potesium, 12%other heavy metal having montmorillonite, Kaolinite and Chamosite clay. Several mud acid treatments have been performed successfully in the shallow depth but the same is not quite effective for deeper pay zone (1700-1800m). Core flow study with mud acid through indicates some precipitation resulting in formation damage and its success in field is limited. Therefore, greater understanding of down hole chemistry and assess the extent of the much slower secondary and tertiary reactions under reservoir conditions is critical for the acid treatment success. Monitoring of metallic ion generation during / after various acidizing treatments gives insight into actual chemical acid-spending processes that occur in the formation.

In the laboratory study, four type of different acid system has been tried with representative core and the resultant dissolution and metallic ion generation processes has been monitored for 3 hours using atomic absorption spectrometry followed by core flow study. Aluminium, Silicon and Iron complexes precipitation observed during secondary and tertiary reaction has been successfully tailored by changing the ratio of HCl:HF and other additives in traditional mud acid system. Results show that RA-1(AlCl3+ HF) acid is little reacting with Silicon whereas RA-2(Phosphonic acid+ ABF) creates Silicon & Calcium precipitation since beginning, thus not suitable. Similarly, RF(HCl+HBF4) creates Silicon precipitation after 150 min in tertiary reaction, whereas, MHF(HCl-HF) acid creates Al precipitation in secondary reaction and Iron precipitation since beginning that is resolved by increasing HCl:HF ratio and adding iron sequestering agent. Core flow study confirms the success of MHF by observing permeability improvement, therefore, suitable for matrix acidization of mehsana formation.

This paper presents a new, effective and economical technique to assess and understand the extent of secondary & tertiary reactions under reservoir conditions that will help in additives selection and making acid formulation for effective matrix acidization of sand stone reservoir that leads to improved field practice.
A New Petrophysical Interpretation Approach To Characterize The Thinly Laminated Reservoir Using Conventional Tools
Authors: Voleti Deepak , Tyagi Anil , Singh Amit , Mundayat Vidya , Pandey Vikram , Saxena Kamlesh
Published: March 2012

Reservoir characterisation in laminated sand shale reservoir has always been a very challenging task. The presence of conductive shales between the resistive hydrocarbon bearing sand reduces its resistivity drastically. It happens as the current flows through them as resistors in parallel. Therefore, the classical shaly sand interpretation grossly underestimates the hydrocarbon potential of laminated reservoir.

Over the years many techniques have been developed to solve this problem. The development of latest resistivity tools like triaxial resistivity has also helped in addressing this problem. The introduction of these tools has helped upto a great extent to unlock the reservoir potential. However, the technology is very costly and sometimes may not be possible to run due the limited extent of the reservoirs. In those cases, it is important to find some alternate approach to addres the problem of low resistivity by using conventional logging tools.

The current study deals with the case history from the East coast deep water field in India. The field has many drilled wells where the latest resistivity tools have been run. Petrophysical interpretations are done using this resistivity anisotropy data and are available for validation with the new technique. The latest approach uses the conventional resistivity data. The critical part in the study is the type and distribution of the shale within the reservoir. If we can find out the same then using this information true resistivity can be inverted. The approach has been tried on several wells across the different fields and has given good results. The results from the resistivity anisotropy data and the new technique are comparable. Thus a very cost effective method of predicting true resistivity has been developed, which ultimately gives realistic hydrocarbon saturation in the laminated sand shale sequences.
Combining State-of-the-Art Uncertainty Management Approaches with Conventional Reservoir Assessment Techniques for an Integrated Brownfield Redevelopment Study
Authors: Hofmann Richard A. , Rana Yogesh , Ratha Bishnu P.
Published: March 2012

This paper describes the results of an integrated study to assess redevelopment options in a mature field with over 40 years of production. The field has been produced under gas cap drive and partly under an internal gas injection scheme to increase oil recoveries. The objective of the study was to confirm the effectiveness and possible expansion of the gas injection scheme and to assess merits of waterflooding.

A two phased modeling approach was adopted and a coarse Phase 1 model for the entire reservoir stack was built using existing interpretations and data available from previous studies while seismic reinterpretation and petrophysical reevaluation to feed the detailed Phase 2 models was ongoing. The Phase 1 model helped to understand the plumbing between the sands and fault blocks and the key parameters impacting field level pressure and cumulative fluid history matches. In Phase 2, two separate models were built for groups of reservoirs at a much finer vertical scale to address sand specific saturation changes and individual well performance.

A structured experimental design (ED) methodology using SUM (Shell proprietary software) was used to explore the full uncertainty space for potential history matches and use calibrated models with the remaining uncertainties to generate a range of forecasts. With the large number of reservoirs involved even a modest number of uncertainties resulted in a large number of ED parameters. The number of parameters and their associated uncertainties was partly narrowed down and constrained in Phase 1 allowing focusing on detailed reservoir specific parameters in Phase 2. In parallel with and complementing the simulation work, conventional contact mapping integrating the historical pressure, water cut and GOR data was carried out to locate potential areas with remaining oil.

This paper will highlight how the phased modeling approach facilitated early integration of reservoir and well performance data for detailed static model construction, ways of managing uncertainty in a brown field with multiple reservoirs, large number of wells and more than 40 years of production history, and finally how traditional reservoir assessment techniques can complement reservoir modeling work.
Injection Water Breakthrough Patterns in Bassein Formation Of Heera Field-A Case Study, Western Offshore, India
Authors: Jha Mamta , Sharma S. S. , Virmani R. K. , Kumar Ajit
Published: March 2012

Heera field is located 70kms south-west of Mumbai city and 140 kms south-east of Mumbai High at an average water depth of about 50m. The field was put on production in November ’84. The oil production is mainly from Bassein, Mukta (carbonates) and Panna (basal clastics) formations. The general dip of the field is towards west. The field produced under depletion drive for about six years till Sept. 90. By this time the reservoir pressure dropped to 1300psi from 2150psi and the field experienced sharp decline in production. Water flooding in Bassein formation started in September ’90. The production stabilized for some time and then again started declining with a sharp rise in water cut. Current average oil rate from the field is 55,892 bopd with water cut of 56% and GOR 145 v/v through 152 producing strings. The average water injection is 1,36,800 bwpd.

The present study aims to identify injection water breakthrough patterns in the producers of Bassein formation of Heera field. The study area is the upper part of mid-Heera field comprising of wells of platforms HD, HQ, HR and HA. The sudden rise in high water content could be due to the breakthrough of injection water in to the producers. Spider diagrams and contour maps were used to interpret the injection water breakthrough patterns in the study area.

Areal distribution pattern as indicated by contour maps of different ions in the study area suggest that there is more influx of injection water in the wells lying on the rising flank of the basin. In the down dip effect of injection water is less. Wells of HA and HD lying on the eastern side are more affected by influx of injection water than wells of platform HR and HQ.
Production Simulator Utilisation for Deep Water Field Optimisation
Authors: Shedd Timmie D , Krishna Sivarama V , Misra Deepti , Mahra Anuradha
Published: March 2012

This paper describes the wide application of Production Simulator System in deep water gas field, its benefits and effectiveness. Deep water and subsea production system requires transportation of a mixture of gas/water through long subsea tiebacks from the producing well to existing production facilities.

Production Simulator System is extensively utilised by Subsea operators for planning their day to day operations and predicting the systems response to current conditions and/or operator actions. The networked production software allows users to optimise and improve the system performance by monitoring wells and facilities.

The optimisation process goes beyond basic operations, but extends into predicting impact of wells/manifolds start-up/shut down, subsea interventions on system performance and its deliverability. The tool also provides study on the integrity of subsea pipelines and critical flow for mid water pipelines to prevent shutdown of manifolds. Simulation studies have presented results, which were precisely similar to the real time data.

While use of long subsea tie backs allows for better project economics, long flowlines causes additional backpressure on the well tending to reduce flow rates due to liquid hold up and/or backpressure increase thereby affecting ultimate recoveries. The succeeding sections in this paper will discuss how such tie-backs tend to under-utilise reservoir energy and presents alternatives for improving field life and enhance the system efficiency.

Efficient monitoring of subsea gas well behavior, subsea system integrity, analyzing subsea pipelines performance and predicting problems with the software optimisation tool has resulted in significantly decreased downtime and effectively assisted in taking decisions for maintaining well production.
ASP Flood Pilot in Jhalora (K-IV) - A Case Study
Authors: Jain Adarsh Kumar , Dhawan A. K. , Misra T. R.
Published: March 2012

Jhalora field, discovered in 1967, is located in the Ahmedabad-Mehsana tectonic block of Cambay basin in India. Reservoir and crude oil properties of all the three main producing sands K-III, K-IV and K-IX+X are quite different. Viscosity of K-IV sand is ~30-50 cp and permeability varies between 1.9 to 8.7 Darcy. Acid number of crude oil is quite high. Water cut is between 80-85%. The mature stage of the Jhalora K-IV with heterogeneous reservoir characteristics and unfavourable mobility ratio makes it an ideal choice for application of chemical EOR technique to enhance the recovery. Based on extensive laboratory and simulation studies one inverted 5-spot pilot was designed. The laboratory studies envisaged additional displacement efficiency of about 23% of Oil Initially in Place (OIIP). Pilot envisaged injection of 0.3 pore volume (PV) Alkali-Surfactant-Polymer (ASP) slug, 0.3PV graded polymer buffer followed by 0.4PV chase water. In order to check preferential movement in the pilot area, profile modification job was done before initiation of pilot. To monitor flood front movement, chemical tracer was also injected.

A meticulous monitoring schedule was drawn. Monitoring is done by measurements of pH, turbidity, Dissolved Oxygen, concentrations of alkali, surfactant & polymer of ASP slug being injected on regular basis. Monitoring schedule also involves fortnightly checking of production rates for each well & weekly testing of water cut. Well head samples from pilot wells are collected on weekly basis and analysis of produced water for presence of tracer & chemical breakthrough is carried out.

In this paper brief results of laboratory investigation leading to implementation of ASP pilot are given. Detailed results of monitoring, problems encountered along-with various steps taken to ensure smooth injection and performance analysis of this pilot so far are given.

Initial results of the ASP pilot are encouraging with additional oil gain of about 47000 bbls after injection of about 0.17 PV ASP slug and expansion of the pilot project is being planned.
Making Good HPHT Invert Emulsion Fluids Great!
Authors: Wagle Vikrant , Maghrabi Shadaab , Teke Kushabhau , Gantepla Anita
Published: March 2012

Barite sag and poor hole cleaning are not problems; they are symptoms of well control and stuck pipe problems. Issues with barite sag and hole cleaning are routinely encountered while drilling high pressure high temperature (HPHT) wells. Maintaining optimal mud rheology in HTHP conditions (350°F+) can be very difficult. Adding organo-clays or low gravity solids (LGS) to boost rheology can lead to high equivalent circulating densities (ECD) and low rates of penetration (ROP).

The new HPHT organic rheology modifier (ORM) imparts optimal rheological properties to low, medium and high density clay-free invert emulsion fluids (IEF). Clay-free systems have previously demonstrated superior gel strength and rheological profiles over conventional organo-clay and lignite treated fluids. Although significant improvement in these systems seemed unlikely, this was accomplished with the new ORM chemistry.

These IEFs exhibit enhanced low shear rheology (even at 9.0 ppg) with lower or similar plastic viscosity (PV) values when compared to IEFs formulated without the new HPHT rheology modifier. When tested at up to 400°F and 18,000 psi, the IEFs formulated with ORM show similar or higher low shear rheology with low PV than under ambient condition. A good low shear rheology implies better hole cleaning and sag control. A low PV improves ECD control.

Treatment with ORM imparts fragile gel characteristics to 9.0 to 18.0 ppg clay-free IEFs. The rapid gel-to-flow transition helps to minimize surge and swab pressures and reduce mud losses. The new HPHT rheology modifier with a biodegradability of 67% in 28 days also stabilizes the IEF and provides comparatively low fluid loss values. It also eliminates the need to add LGS to boost rheology. The paper presents experimental data demonstrating both the environmental and rheological performance of the HTHP rheology modifier as well as comparative data from the conventional clay-free fluids without the ORM.
Meeting the Ultra HTHP Fluid Challenge
Authors: Stamatakis Emanuel , Young Steve , De Stefano Guido
Published: March 2012

Ultra high temperature, high pressure (uHTHP) conditions have a different definition depending on the region and the operator and Service Company. In this paper the definition used for uHTHP fluid performance is that of a fluid able to perform above 500°F and 30,000 psi. This paper describes the development of innovative drilling fluids specific to these well conditions. When bottomhole temperatures exceed 400°F, the design and engineering of drilling fluids can be challenging. Drilling fluids that destabilize can cause a variety of fluid control problems that could lead to drilling and completion issues. With Invert emulsion fluids, the major challenges encountered under these conditions are related to the thermal degradation of the emulsifier and wetting package that can lead to gelation and syneresis. Another challenge is fluid loss which is related to the emulsion stability and to the degradation of the fluid loss control additives. Finally, efficient control over the rheological properties – critical to the success of any well - can also be challenging, where effects from emulsion instability, filtration control degradation and rheology control additive degradation are coupled with increases in drilled solids, rapidly leading to rheological instability. This can manifest itself as high fluctuating rheologies and gelation, or loss of rheological properties that can give rise to sag of weight material, both potentially leading to associated well control problems.

The paper describes the development of the new fluid system designed for such uHTHP environments, highlighting the chemical differences and compares the test data of the system with more conventional HTHP invert emulsion fluids. Data is presented showing the stability and performance of the new fluid over extended exposure to temperature >500°F, demonstrating tolerance to various contaminations and showing the rheological behavior and stability to 600°F and 40,000 psi.
An Integrated Cost Effective Approach for Development of Marginal Fields through Cluster system: A Case Study from Western Offshore Basin, India
Authors: Maji Ashish , Mudiar Binod , Raisinghani Chandar
Published: March 2012

Development of marginal fields in recent time is gaining popularity in view of higher crude oil prices and declining production from brown fields. The discoveries of large fields in mature basins world over are increasingly rare with time. Crude oil production in India is mainly contributed by Western Offshore Basin fields and is undergoing steady decline. To support and sustain the production, marginal fields which have been discovered and remained undeveloped for economical reasons are being taken up for development through innovative strategies and cost optimization. With improved infrastructure and technologies like Sub-sea completion, minimum facility well platform, availability of FPSO, MOPU, Multi Phase Pumps, host of other new ideas available and utilization of various lift technologies will make these marginal discoveries economically viable.

The Cluster-A consisting of three marginal fields (M-1, M-2 and M-3) located East of Mumbai High field and integrated with M-4 additional development (1 new & 1 Side Track well in M-4 field, 1 new well in M-5 Structure) is the case study of cost effective approach for development and early monetization. The bathymetry of the fields ranges from 40-55m. Hydrocarbon accumulations are established in thin multilayered reservoirs consisting of carbonates and finer clastics having in-place oil and gas of around 109 MM BBL and 0.363 TCF respectively.

These fields were discovered in early nineties. Development of these fields remained uneconomical on standalone basis; however, they become viable through cluster system using existing infrastructure and integrating with redevelopment of a nearby brown field and a recent gas discovery.

The development scheme envisages depletion drive, 11 Producers, MOPU for processing; oil evacuation through shuttle tanker and gas to SHG process complex after compression at wellhead platform and a new pipeline from M-4 to BPB Process complex.

This paper presents the technical and business approaches which are critical for development of these smaller isolated fields / prospects through cluster system.
Wellbore Stability in Unconventional Shale - The Design of a Nano-particle Fluid
Authors: Riley Meghan , Stamatakis Emanuel , Young Steve , Price Hoelsher Katerine , De Stefano Guido , Ji Lou , Guo Quan , Friedheim Jim
Published: March 2012

Shale-gas plays and other unconventional resources have gained significant importance worldwide. Historically, synthetic-base drilling fluids (SBM) are used in these plays when no environmental concerns are in place and are preferred when wellbore stability is necessary. In this paper, we study the use of an improved water-base drilling fluid (WBM) that is simple in formulation and maintenance that shows excellent rheological properties, maintains wellbore stability, and a good environmental profile. A combination of well-known and economically affordable materials is combined with new technology to achieve desired rheological properties and wellbore stability.

The use of nanoparticles to decrease shale permeability by physically plugging nanoscale pores holds the potential to remove a major hurdle in confidently applying water-base drilling fluids in shale formations, adding a new advantage to the studied fluid. Silica nanomaterials were investigated for this purpose. Due to their commercial availability, these materials can be engineered to meet the specifications of the formation. Characterization of the nanoparticles was completed with Transmission Electron Microscopy (TEM), dynamic light scattering, and X-ray photoelectron spectroscopy. Rheological properties and fluid loss are studied together with other important properties such as shale stability and anti-accretion properties. The authors will describe new laboratory methods used to investigate these properties, from a modified API fluid loss test to the Shale Membrane Test that measures both fluid loss and plugging effects and illustrate additional future research that includes adding reactive species, and anchoring them to the pores, thus stabilizing the shale further.
A Parallel GA-EDA Hybrid Algorithm for History-Matching
Authors: Abdollahzadeh Asaad , Reynolds Alan , Cristie Mike , Corne David
Published: March 2012

To make prudent decisions regarding the exploitation and management of hydrocarbon reservoirs, we need to carry out history matching, a process for conditioning the reservoir simulation model to observation data collected over time. History matching is an inverse problem which requires an optimisation technique to match the simulation results to the measurements. Many techniques have been applied to address this optimisation problem effectively and in efficient time since reservoir simulation runs are computationally expensive.

Genetic algorithms (GAs) and Estimation of Distribution Algorithms (EDAs) are two popular types of evolutionary algorithms. In GAs, new candidate solutions are obtained by applying crossover and mutation operators to a population of feasible solutions according to the principle of ‘survival of the fittest’ in natural evolution. The Estimation of Distribution Algorithm (EDA) is a modern class of EA in which new candidate solutions are generating by sampling from a probability distribution inferred from the better members of the population.

A suitable hybrid of the GA and EDA algorithms can combine beneficial characteristics from each of GA and EDA, while addressing each other’s sources of inefficiency. The main difference between these two EAs is the way they generate new individuals, which results in different exploration/exploitation properties. GAs may sample bad representatives of good search regions and good representatives of bad regions, while the EDA may suffer from fitting a single probability distribution to diverse and distinct regions of good solutions. The hybrid algorithm performs a cooperative search that improves the exploitation and the exploration power of both algorithms.

In this paper, we applied GA, EDA, and a new hybrid GA-EDA algorithm to optimisation of three cases, a test function, the IC-Fault synthetic reservoir model, and one real reservoir, Teal South. The results show that each of these algorithms can be used for exploring the parameter search space in history matching problem. Depending on the problem type, GA, EDA, and Hybrid GA-EDA can achieve good quality matches while they perform a global seach in the space.