bluuebunny/crossref_metadata_2025 huggingface dataset:
Avaliação para melhoria da qualidade da estratégia saúde da família e a qualificação profissional
Authors: Silva José Mendes da , Caldeira Antônio Prates
Published: February 2017

A proposta Avaliação para Melhoria da Qualidade da Estratégia Saúde da Família (AMQ) foi desenvolvida para oferecer, aos gestores municipais, ferramentas de avaliação e gestão da qualidade da Estratégia Saúde da Família (ESF). No presente estudo, apresenta-se uma perspectiva de avaliação mediante a AMQ, focada na percepção dos profissionais de saúde. Foram realizadas entrevistas com os profissionais de nível superior das três categorias mais envolvidas com a ESF, utilizando-se os instrumentos da AMQ referentes à avaliação de equipes, as quais foram comparadas em relação à qualificação profissional e ao tempo de implantação. As médias dos escores das equipes foram comparadas pelo teste 't' de Student, assumindo-se um nível de significância de 5%. Registrou-se uma percepção positiva das equipes, exceto para as subdimensões 'participação comunitária e controle social' e 'saúde do adolescente'. Equipes qualificadas mediante residência na área de saúde da família mostraram melhor desempenho. Os autores recomendam a ampla utilização do instrumento como forma de divulgação e consolidação da proposta de avaliação e monitoramento da qualidade na ESF e reforçam o papel da residência como medida privilegiada para a qualificação dos profissionais de saúde na atenção primária
Proposta de metodologia para testes qualitativos de mapas 3d
Authors: Schmidt Marcio Augusto Reolon , Delazari Luciene Stamato
Published: February 2017

O uso de representações cartográficas tridimensionais para visualização agrega os últimos avanços tecnológicos para a manipulação e armazenamento de dados espaciais com a capacidade de transmitir informações através de mapas. No entanto, o conhecimento cartográfico necessário para a construção destas representações não acompanhou a evolução tecnológica. Como consequência não existem princípios gerais de projeto cartográfico para a criação de mapas 3D. Uma tarefa comum nessa área é a navegação virtual, que pode ser definida como o processo pelo qual uma pessoa determina sua posição em relação a outros elementos da paisagem e utiliza este conhecimento para chegar a outros locais. Entretanto, a determinação da orientação relativa não é uma tarefa trivial em ambientes virtuais. Alguns auxílios à navegação nesses ambientes foram propostos na literatura, geralmente baseados em técnicas de orientação (chamadas metáforas) utilizadas por usuários para navegar em ambientes reais. Este artigo busca avaliar a eficiência de algumas destas metáforas no desenvolvimento da capacidade de orientação e no cumprimento da tarefa geográfica de navegação. Para isso, foi desenvolvida uma metodologia de testes que associa os métodos qualitativos de registro do raciocínio do usuário (método think aloud) (Elzzaker, 2004), e a avaliação por questionários. O resultado é um procedimento de baixo custo e eficaz na identificação dos elementos de representação utilizados como referência.
Determining the optimal site location of GNSS base stations
Authors: Han Jen-Yu , Wu Yu , Liu Rou-Yu
Published: February 2017

The relative positioning technique plays an essential role in Global Navigation Satellite System (GNSS) surveys. Simultaneous observation at base and rover stations eliminates the majority of error sources thus the quality of a positioning solution can be substantially improved. However, topographic obstruction is still a key issue affecting positioning quality. In this study, an integrated approach for analyzing the impact of topographic obstruction on GNSS relative positioning has been developed. By considering varied satellite geometry according to actual terrain variation, this approach can be used to realistically determine satellite visibility condition for a specific base station with respect to any rover station. Furthermore, a base station quality index (BSQI) is proposed as an explicit indication of the sufficiency in a relative positioning. By incorporating the proposed approach, one can immediately identify an optimal site location for a GNSS base station with subsequent GNSS field survey thus achieved in a more reliable and cost-efficient manner.
Detecção de agrupamentos espaço-temporais para identificação de áreas de risco de homicídios por arma branca em João Pessoa, PB
Authors: Lucena Sadraque Eneas de Figueiredo , Moraes Ronei Marcos de
Published: February 2017

A estatística Scan tem sido comumente usada para identificar conglomerados espaciais de fenômenos adversos a estudos epidemiológicos. Dentre os possíveis modelos, o Poisson e o Permutação Espaço-Tempo são adequados a dados de contagem e assumem na hipótese nula que a distribuição espacial do fenômeno é aleatória. Em estudos espaço-temporais a aleatoriedade é tratada como sendo o risco de ocorrência semelhante em todas as regiões independente do período de tempo. O presente estudo teve por objetivo avaliar o comportamento da estatística Scan para os modelos probabilísticos citados, realizando determinadas alterações na restrição populacional de cada um deles. Para efeito de análise, foram utilizados dados de homicídios por arma branca ocorridos no município de João Pessoa, PB, nos anos de 2001 a 2009. A partir desses dados buscou-se identificar possíveis padrões na ocorrência de homicídios no município e analisar o comportamento espaço-temporal do fenômeno, identificando as áreas de maior risco. Após comparar os mapas do ponto de vista epidemiológico, foi verificado que a estatística Scan utilizando o modelo Poisson com restrição de 7% da população apresentou melhores resultados. O modelo indicou a presença de conglomerados ao longo dos anos nas regiões norte e oeste do município.
Impactos ambientais da mobilidade urbana: cinco categorias de medidas mitigadoras
Authors: Barczak Rafael , Duarte Fábio
Published: February 2017

Desde 1970, a emissão de CO2 no setor industrial cresceu 65% em todo o mundo, contra 120% no de transportes - e 80% da energia utilizada para a mobilidade área urbana têm origem na queima de combustíveis fósseis. Assim, a motorização da mobilidade urbana é um dos principais emissores de gases de efeito estufa. Para analisar este cenário, este artigo toma como base a produção científica internacional produzida do Protocolo de Kyoto (1997) à conferência de Copenhague (2008) para levantar quais principais medidas para a redução do impacto ambiental, especialmente das emissões de CO2. Argumenta-se aqui que são cinco os grupos de medidas a partir da discussão de textos técnicos de órgãos internacionais e produção científica, sendo: econômico-fiscais e financeiras; regulatórias; informação e comunicação; planejamento urbano; e tecnológicas.
Kleingärten: um componente da infraestrutura urbana: aspectos urbanísticos, ecológicos e sociais dos jardins arrendados na Alemanha
Authors: Costa Carlos Smaniotto
Published: February 2017

O presente trabalho traz a conceituação dos chamados kleingärten, um sistema de jardins arrendados, presentes nas cidades alemãs, e enfoca o seu relevante caráter social, bem como o seu potencial na integração à infraestrutura de espaços verdes, como uma alternativa para melhorar a qualidade do ambiente urbano. Esses espaços, que poderíamos chamar de pulmões verdes, pertencem, na maioria dos casos, às prefeituras, que os arrendam a associações de pessoas que queiram plantar verduras, árvores frutíferas e flores. O movimento para a implementação desses jardins, sustentado por uma estrutura institucional, surgiu inicialmente para melhorar a qualidade de vida dos operários nas grandes cidades industriais. Hoje, quase 150 anos mais tarde, o movimento se transformou em uma manifestação cultural, por oferecer uma opção de lazer e recreação ao ar livre para uma boa parte da população e por ser um elemento marcante da paisagem urbana na Alemanha. Isso faz com que os kleingärten, pela sua natureza utilitária, seu interesse paisagístico e urbanístico e sua força política, justifiquem um estudo mais aprofundado.
Full-scale testing to failure of a steel truss railway bridge
Authors: Häggström Jens , Blanksvärd Thomas , Collin Peter , Tu Yongming
Published: February 2017

Significant resources have been invested in maintaining existing infrastructure. Many structures are becoming old, do not meet current requirements, or are reaching the end of their life cycle. It is not feasible or sustainable to replace all of those that may be deemed obsolete; however, often their specified capacities are very conservative. So there is an urgent need to obtain more robust knowledge of their true status. This paper describes a unique project, in which a 33 m long steel truss railway bridge (over the Åby River) was tested to failure. The findings can be used to identify optimal solutions for other bridges of the same design that are still in use, notably the bridge over Rautasjokk (a river in Sweden). These two bridges were tested in three stages. This paper focuses on the second stage, wherein Åby Bridge was subjected to static full-scale testing to failure, by pulling it downwards. The global failure mode consisted of buckling of the top chord with yielding of the steel starting at a total load of 8 MN and the peak load being reached at around 11 MN, corresponding to a load approximately four to five times higher than the characteristic design load.
Genes de patogenicidade de Helicobacter pylori, polimorfismos de citocinas e fatores ambientais afetam o desenvolvimento de doenças gástricas: uma visão geral
Authors: Vianna Júlia Silveira , Almeida da Silva Pedro Eduardo , Bastos Ramis Ivy
Published: February 2017

Justificativa e objetivos: Helicobacter pylori é uma bactéria Gram negativa que coloniza o estômago de aproximadamente 50% da população humana mundial. Este microrganismo é o principal agente causal de gastrite e um importante fator de risco para o desenvolvimento de úlcera péptica e carcinoma gástrico. Os fatores que determinam essa diversidade de manifestações clínicas permanecem incertos, mas podem estar relacionados com a interação dos fatores bacterianos, sistema imune do hospedeiro e variáveis ambientais. O objetivo desta revisão é fornecer uma visão geral destes fatores que influenciam na susceptibilidade a desordens severas de infecção por H. pylori. Método: Para isso, foram selecionados artigos originais e de revisão através da pesquisa nas bases de dados bibliográficos PubMed, Portal de Periódicos CAPES e SCIELO. Resultados: H. pylori possui um conjunto de fatores de patogenicidade, tais como cagA, vacA, iceA, babA, para colonizar a mucosa gástrica e estabelecer infecção crônica. Estes fatores bacterianos são agentes essenciais em modular a resposta imune envolvida na iniciação da carcinogênesegástrica. Os fatores genéticos do hospedeiro contribuem para regular a resposta inflamatória e parao agravamento da lesão damucosa gástrica uma vez que a infecção gástrica por H. pylori induz a produção de várias citocinas pró e anti-inflamatórias no hospedeiro. O papel prejudicial dos fatores ambientais está relacionado com as precárias condições socioeconômicas, com o consumo de sal, com o tabagismo e com o consumo de álcool. Conclusão: Ao decifrar as regras deterministas - se houver - dessa interação entre fatores da bactéria, do hospedeiro e variáveis ambientais, será possível prever, tratar e, finalmente, prevenir graves doenças gastroduodenais.
Atuação do farmacêutico residente em uma unidade de pronto atendimento: contribuindo para a promoção da saúde
Authors: Moraes Greice Graziela , Da Rosa Karini , Frantz Mara Regina , Sulzbacher Batista Matheus , Helfer Schneider Ana Paula
Published: February 2017

Justificativa e objetivos: A prática da Farmácia Clínica em hospitais é de fundamental importância, na qual o farmacêutico presta cuidado ao paciente, possibilitando assim otimizar a farmacoterapia, promover a saúde e bem-estar, além de prevenir doenças e desenvolver a qualidade do cuidado à saúde. Assim, o objetivo deste estudo foi quantificar a ocorrência de potenciais interações medicamentosas, incompatibilidades e intervenções farmacêuticas realizadas em prescrições de pacientes atendidos em uma unidade de Pronto Atendimento (PA). Métodos: É um estudo descritivo e quantitativo. As atividades foram desenvolvidas em um hospital de ensino localizado no interior do Rio Grande do Sul no período de abril a julho de 2016, por profissionais Farmacêuticos Residentes. A amostra deste estudo foi composta por 265 prescrições de 107 pacientes. Resultados: Houve predominância do sexo masculino (51,4%), com média de 63,41 anos. Foram identificados 2.087 medicamentos prescritos, com média de 7,9 (± 3,4) medicamentos por prescrição. Das 265 prescrições analisadas, foram encontradas interações medicamentosas em 25,6% e 2,3% de incompatibilidades medicamentosas. Realizaram-se intervenções de trocas de horários em 5,66% e 4,52% de reconciliação medicamentosa. Conclusões: O farmacêutico clínico é de fundamental importância no ambiente hospitalar, visto que o estudo revelou-se uma frequência de 25,66% de interações medicamentosas e 2,26% de incompatibilidades. Realizou-se ainda, intervenções farmacêuticas de trocas de horários de administração de medicamentos em 5,66% das prescrições e em 4,52% de reconciliação medicamentosa, ressaltando assim, que o Serviço de Farmácia Clínica tem grande impacto no aumento da segurança ao paciente e prevenção de eventos adversos.
Los beneficios fiscales en las tasas locales
Authors: Sánchez Robert Trinidad
Published: February 2017

El establecimiento de beneficios fiscales en la Hacienda local constituye una exigencia de la necesidad de respetar los principios constitucionales de justicia tributaria y, en particular, el principio de capacidad económica. En este trabajo se va a analizar la problemática del establecimiento de  beneficios fiscales en las tasas locales, partiendo de un necesario estudio sobre la evolución del concepto de tasa, así como de su naturaleza y fundamento. Pero sobre todo, se tendrá en cuenta, y este tema también afecta al ámbito estatal y autonómico, la especial dificultad que entraña la caracterización de esta categoría tributaria en orden a su adaptación al principio de capacidad económica.Palabras clave.- Beneficios fiscales, tasas locales.
LGBT Family Camp as Cultural Immersion for Social Work Students
Authors: Mercier Lucy , Harold Rena , Johnson Kimberly , Pond Debora
Published: February 2017

This article presents a model, based on traditional study-abroad programs, for social work students' cultural immersion with local populations. Students who volunteered at an LGBT-parent family camp reported on the impact of the experience in the areas of knowledge about diversity, professional and personal identity, skill development, and managing emotional reactions. Data analysis suggested that learning occurred in all areas identified in the model. BSW students reported increased awareness of the importance of social policy and advocacy skills, leadership characteristics, ability to work with others, and self-awareness as foundations in working across cultural difference. The authors suggest that participants acquired skills generalizable across cultures and applicable to the diverse settings in which social workers practice. Implications include suggestions for social work pedagogy relevant to the development of meaningful goals for teaching about culture in social work programs.
Appendicular lump: comparative study of immediate surgical versus conservative management
Authors: Agarwal Vimal K. , Agrawal Sonal
Published: February 2017

Background: At present acute appendicitis is leading cause of acute surgical abdomen. Treatment of choice for non-complicated appendicitis is appendicectomy. Delayed presentation of appendicitis cause lump formation in 2-6% case. Traditional treatment of appendicular lump is conservative treatment followed by interval appendicectomy. Our study was done to make a better management plan for lump patients.Methods: In this retrospective study 52 patients having appendicular lump randomly divided in two group, Group 1 conservative treatment followed by interval appendicectomy after 6-8 weeks and group 2 immediate surgery. Highest incidence of appendicular lump was found in age group of 21-30 year. Average hospital stay in group 1 was 12 days as compare to 4 day in group 2.Results: Immediate surgery in our study suggest better management plan for appendicular lump in term of less hospital stay, less economic burden, no need of readmission in hospital and no major complication.Conclusions: Early exploration for appendicular lump is preferred option rather than conservative treatment followed by interval appendicectomy.
Role of procalcitonin in early diagnosis of neonatal sepsis
Authors: Hasan Fareedul , Khan Shamshad A. , M. K. Maharoof , Muhammed Niyaz
Published: February 2017

Background: Neonatal sepsis is the most common cause for neonatal mortality and morbidity in India, Therefore it is essential that we diagnose early onset sepsis using clinical signs and symptoms and rapid diagnostic techniques and start appropriate treatment without any delay. Various diagnostic tests that differentiate infected and non-infected neonates particularly in the first few days of life can potentially make significant impact on the neonatal care.Methods: This was a hospital based clinical prospective study, done in the NICU department of pediatrics at Yenepoya medical college hospital, from January 2013 to December 2013. Sample size in this study was 50. All consecutive neonates fulfilling the inclusion and exclusion criteria were subjected to investigations like serum Procalcitonin, CRP, Total count, Gastric aspirate, Peripheral smear and Blood culture before starting treatment with antibiotics. Positive blood culture was taken as proven sepsis. The results obtained from our study parameters were statistically compared with cases of proven sepsis. Results: In our study 16(32%) out of 50 neonates had proven sepsis. In comparison to the other  markers of neonatal sepsis Elevated levels of serum Procalcitonin was found to be the most sensitive test with sensitivity of 100%, specificity of 50%, positive predictive value of 48.5%and negative predictive value of 100% and with a very highly significant p value of <0.001.Among the levels of PCT moderately elevated (2-10ng/dl) had sensitivity of 100%, specificity of 84.5%, PPV of 62.5% and NPV of 100% and highly elevated (>10ng/dl) had sensitivity of 100%, specificity of 80%, PPV of 75% and NPV of 100%.Conclusions: The use of procalcitonin in the diagnosis of neonatal sepsis has proved to be very useful compared to other regular sepsis markers. Procalcitonin performs better than CRP in the diagnosis of neonatal infection. Serum Procalcitonin levels >2 ng/dl has got a better sensitivity; PPV and NPV thus help us not only in the early diagnosis and also in the prognosis of the treatment and helps us in guiding in reducing the unwanted usage on antibiotics.
Evaluation of predictive value of total leukocyte count in acute serious bacterial infections in children 1 month to 5 years
Authors: A. Dharmalingam , C. Vignesh , N. S. Raghupathy , M. Sowmiya
Published: February 2017

Background: Fever in a young child is a frequently encountered clinical problem with various causes. Most of them run a benign self-limiting course that requires only symptomatic treatment. However, in a few children the underlying etiology can be a life threatening serious bacterial infection (SBI). Early identification of SBI is warranted because of the need to start antibiotic therapy, often empirical, as soon as possible to prevent morbid sequela. Total leukocyte count (TLC) is with neutrophil predominance is considered to be a surrogate marker of a bacterial infection and facilitating decision - making regarding further evaluation and empiric antibiotic therapy. The purpose of this study was to determine the utility of leukocyte in predicting SBI in a young febrile child and to correlate the leukocyte count with non-serious infection.Methods: One fifty children, age of 1 month to 60 months with fever > 38°c are included and were analyzed for demographic details, presenting symptoms, physical examination findings, clinical diagnosis, total leukocyte count, peripheral smear study, blood culture, stool culture, CSF analysis, x-ray chest, abdominal ultrasound, CT-brain. Results: Out of 150 children included in the study, the mean age was 26.7±14.54 months and the average duration of fever was 4.3±1.02 days. The mean leukocyte count was 15016.43±5801.98 cells/cu.mm. 74 children had proven serious bacterial infection (49.3%) and were categorized in Group I and remaining non-serious infection were 50.66% are belonged to Group 2. Urinary tract infection and pneumonia were the most common SBI encountered (31/20/68.91%). The highest TLC counts were seen in children with UTI. Analysis of variance (ANNOVA) did not reveal significant differences in TLC between children with different diagnosis. In Group 2, majority of the etiology was lower respiratory tract infection/inflammation and short febrile illness.Conclusions: SBI comprise only half of the febrile children with leukocytosis. The predictive accuracy of leukocytosis in diagnosing SBI is poor. Vomiting and seizures probably incite stress mediated leukocytosis and are commonly encountered in febrile child with a high TLC without SBI. Further models with addition of clinical data and other surrogates of infection need to be developed to improve prediction of SBI in a febrile child.
European Capitals of Culture
Authors: Sianos Alexandros
Published: February 2017

Using English-language newspaper articles retrieved from digital repositories, this article examines the cultural asymmetrical encounter between Western and Eastern Europe after 1989. It argues that due to the rise of the Iron Curtain after 1948 and the post-war progress of the Western European integration project after 1950, the idea of ‘Europe’ was confined to the West until 1989. After 1989, however, the Eastern European nations were free to ‘return to Europe’, and in order to do so they followed the ‘reference model’ of the West. Taking the institution of the European Capital of Culture (ECOC) as a case study, the article demonstrates how both Western and Eastern European cities used the ECOC title as a gateway to modernity, why it acquired an extra functionality in the East as a stage where they could showcase their ‘European’ credentials, and how it gradually developed into one of the EU’s ‘soft power’ resources.
¿Por qué Bogotá no tiene al menos una línea metro? Y las razones por las que probablemente no la tendrá
Authors: Alfonso Roa Óscar A.
Published: February 2017

No obstante que la decisión sobre la primera línea metro para Bogotá se esbozó hace 75 años, en la actualidad la ciudad no cuenta con ella, pero tampoco existe una reflexión académica acerca de las razones para tal rezago. Durante este lapso de tiempo, el capital físico e institucional destinado a la movilidad se ha deteriorado al punto de llevar al colapso al sistema de transporte masivo de pasajeros, que tiene varias manifestaciones, siendo las más notables el incremento sustancial en los tiempos improductivos de viaje, la congestión vehicular, la saturación del parque automotor destinado a la movilidad colectiva y la inseguridad personal a la que se exponen los usuarios. En este artículo se sustenta la idea de que en una metrópoli de ocho millones de habitantes, con poderosas inflexibilidades infraestructurales, el trazado de la línea prioritaria del metro debe resolverse en favor de conectar las zonas más densamente pobladas de la ciudad, con lo que se resolverían secuencialmente los rezagos de inversión y se dotaría de mayor sostenibilidad ecológica y financiera al sistema de transporte masivo de pasajeros.
Urgency Competence of Media Literacy for Archivist
Authors: Santoso Agus
Published: February 2017

The study of media literacy has been conducted by the earlier scientists. That research uses population that have different characteristics to each other. So this studies of media literacy have various models or patterns. This models or patterns of media literacies will be used as basic data to the next study that generated will usually be the basis for the further research. Basically, the model of media literacy generated by some researchers only can be applied in the population which become objects of research. To day, the archives faced many challenges due to the presence of information technology, so that the competence of media literacy as one of the important competencies to have. Through this competency, archivist are expected to manage archives organization effectively and efficiently. This paper uses a descriptive method to describe how media literacy becomes important for archives.
The Analysis Condition of Special Library for Street Children at UPTD "Kampung Anak Negeri” Institutions
Authors: Mutia Fitri
Published: February 2017

The existence of special library UPTD the "Kampung Anak Negeri" became one medium that can be used to develop the potential of street children themselves a growing number from year to year. This study conducted descriptive quantitative research that aim to describe the condition of special libraries in UPTD “Kampung Anak Negeri", especially in terms of collections, facilities and infrastructure, library services and human resources (librarian). The four aspects are then compared with the standard of the special library collated by the National Library in 2011. In this study, data collection technique conducted in July 2016 using interview techniques as a primary technique performed on librarians and include interviews with street children as well as staff of Colleagues   staff UPTD.  Based on the data obtained can be concluded that the amount of the book collection of about 752 titles of books, collection development has not reached 5% per year, spacious room just 35m² and has only 2 rack collection. Services available are services in place read, circulation services and information search services, while the librarians who manage only one person with a background in library and information science education. In general, special libraries UPTD condition does not meet the standard, so this affects is not maximized to support learning process as well as in facilities that match the information needs of street children.
Eco-Safety Assessment of Glyoxal-Containing Cellulose Ether on Freeze-Dried Microbial Strain, Cyanobacteria, Daphnia, and Zebrafish
Authors: Park Chang-Beom , Song Min Ju , Choi Nak Woon , Kim Sunghoon , Jeon Hyun Pyo , Kim Sanghun , Kim Youngjun
Published: February 2017

The objective of this study is to investigate the aquatic-toxic effects of glyoxal-containing cellulose ether with four different glyoxal concentrations (0, 1.4, 2.3 and 6.3%) in response to global chemical regulations, e.g., European Union Classification, Labeling and Packaging (EU CLP). Tests of the aquatic-toxic effects of glyoxal-containing cellulose ether on 11 freeze-dried microbial strains, Microcystis aeruginosa, Daphnia magna and zebrafish embryos were designed as an initial stage for toxicity screening, and were performed with the standardized toxicity test guidelines. Glyoxal-containing cellulose ether showed no significant toxic effects in the toxicity tests for the 11 freeze-dried microbial strains, Daphnia magna and zebrafish embryos. Alternatively, 6.3% glyoxal-containing cellulose ether led to more than a 60% reduction of Microcystis aeruginosa growth after 7 days of exposure. Approximately 10% developmental abnormalities (e.g., bent spine) in zebrafish embryos were also observed in the group exposed to 6.3% glyoxal-containing cellulose ether after 6 days of exposure. These results imply that <6.3% glyoxal-containing cellulose ether results in non-toxic effects on the acute toxicity of aquatic organisms. However, ≥6.3% glyoxal-containing cellulose ether may affect the health of aquatic organisms with long-term exposure. In order to better evaluate the eco-safety of cellulosic products contained in glyoxal, further studies regarding the toxic effects of glyoxal-containing cellulose ether with long-term exposure are required. The results from this study allow us to evaluate the auatic-toxic effects of glyoxal-containing cellulosic products, under EU chemical regulations, on the health of aquatic organisms.
Effect of PEG-2000 on saturation magnetization Fe3O4 particles synthesized with coprecipitation method
Authors: Puryanti Dwi , Andani Dori , Thressia Merry
Published: February 2017

Synthesis of Fe3O4 particles was performed using coprecipitation method. Iron sand base material obtained by processing the iron rocks by means of destruction and extraction. Iron rocks were taken from the village Surian, South Solok of West Sumatera. Iron sand that has been extracted reacted with HCL and NH4OH. Furthermore, the PEG-2000 were added to see its effect on the resulting magnetization saturation. Variations in the composition ratio of iron sand and PEG-2000 are 1:0, 1:1, 1:2 and 1:4. The crystal structure of the sample was confirm using x-ray diffraction method. Characterization of magnetic properties carried out using vibrating Sample Magnetometer (VSM). The results of magnetic properties show that the saturation magnetization decreases with increasing of PEG-2000 content in the range of 99.50emu/g - 0,84 emu/g.
Application of problem based learning model to learning outcomes of student in light matter in the class VIII SMP Negeri 1 Ledo kabupaten Bengkayang
Authors: Sari Ira Nofita , Wahyudi Wahyudi , Hendrias Hendrias
Published: February 2017

This study aims to determine: (1) student learning outcomes after application of the model Problem Based Learning on the material light in class VIII SMP Negeri 1 Ledo Bengkayang, (2) student learning outcomes after application of conventional learning models on the material light in class VIII SMP Negeri 1 Ledo Bengkayang, and (3) a comparison between student learning outcomes after application of Problem Based learning and conventional learning models in light of the material in class VIII SMP Negeri 1 Ledo Bengkayang. This study design is Nonequivalent Groups Post-Test Only Design. The study population was all students of class VIII SMP Negeri 1 Ledo consisting of four classes, namely class VIII A, VIII B, C VIII and VIII D. The research sample was determined by random cluster sampling technique and obtained a class VIII A as the experimental class and class VIII C as the control class. The data collection technique used is the technique of measurement, with the data collection tool is test description. The hypothesis was tested using the t test of the parties. Based on the analysis concluded that: (1) the average student learning outcomes after application of the model Problem Based Learning on light material in class VIII SMP Negeri 1 Ledo Bengkayang is 73.24, (2) student learning outcomes after application of conventional learning model in the light of the material in class VIII SMP Negeri 1 Ledo Bengkayang is 69.82, and (3) student learning outcomes after application of the model Problem Based learning is better than the student learning outcomes after application of conventional learning models in light of the material in class VIII SMP Negeri 1 Ledo Bengkayang

 
A Modeling Study of EOR Potential for CO2 Huff-n-Puff in Tight Oil Reservoirs - Example from the Bakken Formation
Authors: Kanfar M. S. , Ghaderi S. M. , Clarkson C. R. , Reynolds M. M. , Hetherington C.
Published: February 2017

The most commonly used technology for development of unconventional liquid-rich and light oil reservoirs is horizontal wells combined with large multi-stage hydraulic fracture treatments. However, even with these technological advancements, primary recovery factors are generally less than 10% (Shoaib and Hoffman, 2009) of the original oil in place (OOIP). Logically, operators have investigated the use of waterflooding to improve recovery in some tight oil reservoirs, but the success has been mixed. Low matrix permeability in some unconventional (tight) oil reservoirs will not allow effective displacement or movement of water through the reservoir. In some cases, even flooding with a gas will be a challenge, if matrix permeabilities are too low.

This study investigates the feasibility of enhanced oil recovery (EOR) in a prominent tight oil reservoir in North America using cyclic solvent injection (CSI, sometimes referred to as "huff-n-puff") with carbon dioxide (CO2) as the solvent. CSI is a single well process, with the solvent remaining in the vicinity of the wellbore, as flow of the solvent through the reservoir to another well is not necessary. This type of process may be attractive from a capital cost point-of-view, as large expenditures on specialized facilities, in-field pipelines and well conversions are unnecessary.

In this study, the success and profitability of huff-n-puff is evaluated for the Bakken tight oil reservoir. Knowledge gained from a parallel study (Kanfar and Clarkson, 2017) served to provide guidelines for optimizing the huff-n-puff process. Importantly, a genetic algorithm (GA) is utilized to find the optimum huff-n-puff program that maximizes net present value (NPV). Optimized parameters include: the number of cycles; duration of injection, soaking and production periods; and the start time of huff-n-puff operations. The target reservoir for evaluation is the US Bakken deep tight oil reservoir in North Dakota.

The huff-n-puff EOR scheme was found to be successful, but only after the aforementioned operational parameters are optimized with GA. In particular, it is important to delay huff-n-puff until production rates decline and boundary-dominated flow (after fracture interference) is reached. Importantly, as with the parallel study (Kanfar and Clarkson 2017), the gridding scheme used in the simulation is found to have a profound impact on results of huff-n-puff.
Adaptive Fracturing to Avoid Frac Hits and Interference: A Wolfcamp Shale Case Study
Authors: Paryani M. , Smaoui R. , Poludasu S. , Attia B. , Umholtz N. , Ahmed I. , Ouenes A.
Published: February 2017

This paper presents a new integrated workflow that couples geology, geomechanics and geophysics (3G) with a constrained asymmetric frac model as applied to a Wolfcamp well to address the concerns of well interference. The proposed workflow enables the ability to adapt the frac design of each stage based on the in-situ geologic and geomechanical variability. The objective of this approach is to identify the variable treatment parameters required to overcome the stress heterogeneity and estimate the impact of the adaptive frac design on the final fracture geometry.

The lateral stress gradients resulting from the pressure depletion due to a nearby producing well and the fluid leak-off due to opening of natural fractures are fine-tuned to account for asymmetry observed in the geomechanical modeling. The role of the natural fractures is emphasized and practical approaches to estimate a validated natural fracture model are described and illustrated. A validation well is used to highlight the importance of the input natural fracture model in calculating validated differential stress and strain that reproduce the main features of the microseismic. With this validated strain model, a constrained frac design provides the proper asymmetric fracture geometry able to pinpoint the poor and good frac stages. Once the workflow is extensively validated, it can be used on target wells to avoid frac hits.

In this Wolfcamp example, the challenge was to find the optimal frac design to minimize interference of an infill well with existing offset producers. To address the possible zones of interference, the stage spacing was locally increased to 152 m (500 ft), and the treatment was especially modified in the middle stages of the well. This resulted in reducing the number of stages from 40 to 34, specifically in zones indicating high probability of interference. The design was altered from pumping a mixture of 320,000 lb of 100 mesh and 40/70 mesh sand to 220,000 lb of 40/70 mesh sand, and the injected fluid viscosity was increased from 10 centipoise (cP) for slick water to 30 cP for linear gel as better carrying capacity was required to pump only 40/70 mesh sand. Additonally, the injection rate was reduced from 105 bbl/min to 80 bbl/min.

The integrated approach allows for the ability to adapt the frac design to in-situ conditions including heterogeneity in the stress fields and the pressure depletion from existing producers. Adaptive frac design significantly reduces the probability of frac hits and well interference. The proposed modeling workflow enables greater investment efficiency and overall field development optimization.
Lithofacies Classification for Earth Modeling: Letting the Data Speak For Itself
Authors: Gevirtz Joel , Ovalle Adriana
Published: February 2017

Common earth modeling practice propagates rock properties into the model from depositional lithofacies obtained from log and core analyses. The primary objection to this method is that the rocks, particularly carbonates, do not truly reflect the depositional framework. Diagenetic and other post-depositional processes have extensively modified the rocks. These processes tend to homogenize depositional fabrics, thus obliterating specific relationships needed to accurately predict and propagate properties.

Geologically reliable lithofacies for conventional and unconventional reservoir modeling can be obtained with unsupervised multivariate classification procedures applied to suites of log curves. Data analytics applied to log data can provide lithologies and flow units across the reservoir. Important rock properties that are critical inputs for a static earth model are included as part of the lithofacies definition.

Because lithofacies obtained from logs are partially based on the analysis of crossplots calibrated to rocks when possible, log-based facies definitions are subject to the experience-based bias of the project interpreter. Crossplots used for facies analysis often show complex patterns that suggest the multivariate nature of relationships between individual logs. Incorrect facies specification can lead to an inaccurate depiction of the lithologic geometry, which is a key shortcoming of this approach. The paper describes data analytics as applied to log data, developed as an aid to understanding lithologies and flow units across a stratigraphic interval.

A workflow was created that enables natural groups inherent in the data to be obtained. This approach does not require a priori rock type information. Multivariate procedures are applied to a selection of curves that comprise a log suite over an interval of interest to obtain log response groups based on log curve variation. These response groups can be used to propagate critical porosity and permeability data into the model.

The workflow described in this paper was successfully applied in several mature areas that include unconventional plays in the Delaware and Midland basins of west Texas and the Burgos basin of Mexico. New well locations and horizontal drilling targets selected with the recommended methods have performed significantly better than wells drilled without using this approach.

The new approach to rock typing presented in this paper is compatible with modern earth modeling methods and can improve drilling success by highlighting areas with more favorable rock properties. The sequence in which individual methods are applied is important in this workflow. Assumptions regarding distributional properties of the individual data elements are not required. Experience shows that this workflow provides improved understanding of lithological variation over the volume of interest, increasing the probability of better well performance.
Multiscale Imaging of Gas Adsorption in Shales
Authors: Aljamaan Hamza , Ross Cynthia M. , Kovscek Anthony R.
Published: February 2017

Four intact one-inch diameter cores from different shale plays (Barnett, Haynesville, Eagle Ford, and Permian Basin) were analyzed for their gas storage capacity using a novel multiscale imaging methodology spanning from cm- to nm-scale. Gas storage capacity was investigated at the core-scale with carbon dioxide (CO2) and krypton (Kr) using X-ray computed tomography (CT) with voxel dimensions of 190×190×1000 μm. Also, 2D tiled images were acquired using a scanning electron microscope (SEM) and stitched together to form one-inch diameter mosaics with a pixel resolution of 1.5 μm. Multiscale image registration was then carried out to align the CT data with the SEM mosaics. Energy dispersive spectroscopy (EDS) generated elemental spectra maps and subsequent component maps for regions with either substantial or minimal gas storage to assess the interplay of structural features (e.g., fractures) and matrix composition with respect to gas accessibility and adsorption.

Registration of CT scans (vacuumed and gas-filled) as well as 190 µm-resolution CT-derived gas storage maps with 1.5 µm-resolution SEM mosaics is straight forward for samples with dense features (such as calcite-filled fractures) that are resolvable by CT imaging. Alignment methods were developed for samples lacking these features including registration marks using silver paint and intermediate resolution microCT scans with cubic voxel dimensions of 27 μm. Once aligned, the relationship of enhanced adsorption zones with open fractures and reduced adsorption regions with secondary mineralization (such as nodules) is apparent for the carbonaceous samples. For the clay-rich Barnett sample, fracture-filling calcite is associated with reduced adsorption similar to the other samples; however, secondary carbonate cementation within the clay matrix aligns with regions with substantial Kr and CO2 gas storage. In contrast, clay-rich matrix regions lacking secondary carbonate cementation exhibit minimal gas storage potential. Causes for this unexpected result include reduced gas accessibility and, possibly, low organic matter content in the clay-rich matrix compared to secondary cemented matrix.

These gas adsorption experiments prove the feasibility of dynamic core- to nm-scale CT/SEM/EDS image registration to improve sample characterization. To our knowledge, this is the first investigation of core-scale CO2 gas adsorption employing multiscale imaging. CT and SEM image registration reveal spatial details regarding gas accessibility and storativity at the core-scale. This work also supports the potential of carbon storage in shale formations as well as guides engineers toward optimal CO2 injection zones for enhanced gas recovery.
Historical Terminal Decline Rates Review of Unconventional Reservoirs in the United States
Authors: Hale Brent W , Hall Russell K
Published: February 2017

The United States has had a significant oil and gas industry since Mr. Drake's oil well in Pennsylvania in 1859 attracted attention to the drilling of wells to produce oil. In the last decade, technology advances in both drilling and completion technology have had a significant impact on the ability to develop oil and gas reserves and have produced a new generation of wells for which extensive histories are not available at this time. A review of available historical data helps establish reasonable limits for decline trends of newer developments.

In order to better place limits on terminal decline rates for unconventional plays, data are presented showing terminal decline rates for a selected vertical developments and for selected horizontal developments in the United States. The curves reviewed include 292 type wells in 54 different producing horizons in the United States.

Some oil and gas developments have over 60 years of history and low decline rates. Others have high initial decline rates which do not flatten as expected for horizontal wells in low permeability reservoirs. The data for many of the developments also shows that decline trends beyond 10 to 20 years are frequently impacted by workovers and recompletions which have a significant impact on projected decline rates for a large number of long life wells.

Where both vertical and horizontal wells have been developed in an unconventional play, vertical well decline rates are generally less than horizontal well decline rates. The data also shows that gas decline rates are generally less than oil decline rates. When considered as a group, there is a band of decline rates which establishes reasonable upper and lower limits for newer developments using horizontal drilling and newer completion technology.
Experimental Investigation for Microscale Stimulation of Shales By Water Imbibition During the Shut-in Periods
Authors: Gupta Aadish , Xu Mingxiang , Dehghanpour Hassan , Bearinger Doug
Published: February 2017

Imbibition of water into the shale matrix is known as the primary reason for inefficient water recovery after hydraulic fracturing treatments. The hydration of clay minerals may induce microfractures in clay-rich shale samples. The increased porosity and permeability due to induced microfractures has been considered to be partly responsible for 1) excessive water uptake of gas shales, and 2) increase in hydrocarbon production rate after prolonged shut-in periods. To test this hypothesis, it is necessary to measure imbibition-induced strain and stress under representative laboratory conditions.

In this study, we conduct laboratory tests to 1) measure the strain and stress induced by water imbibition in gas shales and 2) investigate the effect of confining load on the rate of water imbibition. We conduct a three-phase study on rock samples from the Horn River Basin (HRB) and the Duvernay (DUV) Formation, located in the Western Canadian Sedimentary Basin. In the first phase, we measure baselines for water and kerosene imbibition into the rock samples by conducting spontaneous imbibition tests. In the second phase, we measure expansion of the rock samples during imbibition of water and kerosene, in separate tests, using a linear variable differential transformer (LVDT). In the third phase, we measure imbibition-induced tensile stress during water imbibition into the samples.

The results show that both HRB and DUV shale samples imbibe more water than kerosene, due to water adsorption by clay minerals. Imbibition of water increases the porosity of the HRB and the DUV samples by up to 0.94 and 0.25 percentage points, respectively. Expansion of all samples is anisotropic, with higher expansion perpendicular to the depositional lamination. Water imbibition into the samples induces an expansive stress as high as 17 psi. Moreover, applying confining stress reduces the imbibition of water by up to 18.1% and 33.7% in the HRB and DUV samples, respectively.