bluuebunny/crossref_metadata_2025 huggingface dataset:
A feasibility study on beef tallow conversion to some esters for biodiesel production
Authors: Ghazavi Mohamad Ali , Fallahipanah Majid , Jeshvaghani Hamed Shahmirzae
Published: March 2013

Background

Nowadays, management and recycling of industrial by-products are one of the most important issues in developing and developed countries. Beef tallow is one of these residues produced in slaughter houses and primarily is utilized in soap production industry. However, when this industry is overloaded, the extra fats are usually incinerated or disposed in a sanitary landfill. However, beef tallow may be consumed in biodiesel production. Therefore, in this work, the process of biodiesel production in a pilot plant has been studied using beef tallow as raw material with methanol and potassium hydroxide as catalyst. The quality of the produced biodiesel is evaluated using Fourier transform infrared spectroscopy (FTIR) method.

Results

FTIR analysis showed that the final product contains ester compositions which can be used as biodiesel fuel in diesel engines. The viscosity of natural beef tallow was very high, and actually, it was solid; however, after transesterification the viscosity of the final product decreased, and it became liquid. The viscosity of the final product measured at 40°C was 5.3 mm2 s−1, and the comparison of this biodiesel with the data of ASTMD-445 standard resulted in the similarity of this product with petroleum diesel (3 to 12 mm2 s−1).

Conclusions

Alkaline transesterification of beef tallow with methanol decreases the viscosity of the final synthesized product and produces a high quality biodiesel for diesel engines. Beef tallow is one of the low cost residual materials available in slaughter houses. Therefore, the slaughter houses can be considered as one of the available sources to produce biodiesel. In this research, the process of biodiesel production from beef tallow was validated, but the economical viability must be improved by recovering methanol and glycerol.
Modeling the heterogeneity in risk of progression to Alzheimer's disease acrosscognitive profiles in mild cognitive impairment
Authors: Tatsuoka Curtis , Tseng Huiyun , Jaeger Judith , Varadi Ferenc , Smith Mark A , Yamada Tomoko , Smyth Kathleen A , Lerner Alan J ,   The Alzheimer's Disease Neuroimaging Initiative
Published: March 2013

Introduction

Heterogeneity in risk of conversion to Alzheimer's disease (AD) among individualswith mild cognitive impairment (MCI) is well known. Novel statistical methods thatare based on partially ordered set (poset) models can be used to create modelsthat provide detailed and accurate information about performance with specificcognitive functions. This approach allows for the study of direct links betweenspecific cognitive functions and risk of conversion to AD from MCI. It also allowsfor further delineation of multi-domain amnestic MCI, in relation to specificnon-amnestic cognitive deficits, and the modeling of a range of episodic memoryfunctioning levels.

Methods

From the Alzheimer's Disease Neuroimaging Initiative (ADNI) study, conversion at24 months of 268 MCI subjects was analyzed. It was found that 101 of thosesubjects (37.7%) converted to AD within that time frame. Poset models were thenused to classify cognitive performance for MCI subjects. Respective observedconversion rates to AD were calculated for various cognitive subgroups, and byAPOE e4 allele status. These rates were then compared across subgroups.

Results

The observed conversion rate for MCI subjects with a relatively lower functioningwith a high level of episodic memory at baseline was 61.2%. In MCI subjects whoadditionally also had relatively lower perceptual motor speed functioning and atleast one APOE e4 allele, the conversion rate was 84.2%. In contrast, the observedconversion rate was 9.8% for MCI subjects with a relatively higher episodic memoryfunctioning level and no APOE e4 allele. Relatively lower functioning withcognitive flexibility and perceptual motor speed by itself also appears to beassociated with higher conversion rates.

Conclusions

Among MCI subjects, specific baseline cognitive profiles that were derived throughposet modeling methods, are clearly associated with differential rates ofconversion to AD. More precise delineation of MCI by such cognitive functioningprofiles, including notions such as multidomain amnestic MCI, can help in gainingfurther insight into how heterogeneity arises in outcomes. Poset-based modelingmethods may be useful for providing more precise classification of cognitivesubgroups among MCI for imaging and genetics studies, and for developing moreefficient and focused cognitive test batteries.
Comparison of three molecular assays for the detection and molecular characterization of circulating tumor cells in breast cancer
Authors: Strati Areti , Kasimir-Bauer Sabine , Markou Athina , Parisi Cleo , Lianidou Evi S
Published: March 2013

Introduction

Comparison studies between different analytical methodologies for circulating tumor cells (CTC) detection and molecular characterization are urgently needed, since standardization of assays is essential before their use in clinical practice.

Methods

We compared three different CTC molecular assays. To avoid discrepancies due to pre-analytical errors we used the same cDNAs throughout our study. CTC were isolated using anti-EpCAM and anti-MUC1 coated magnetic beads from 2 × 5 ml of peripheral blood of 254 early and 51 metastatic breast cancer patients and 30 healthy individuals. The same cDNAs were analyzed by: a) singleplex RT-qPCR assay for CK-19; b) multiplex RT-qPCR for CK-19, HER-2, MAGE- A3, and PBGD; and c) a commercially available molecular assay (AdnaTest BreastCancer) for GA733-2, MUC-1, HER-2 and beta-actin.

Results

In early breast cancer, CK-19 RT-qPCR, multiplex RT-qPCR and the AdnaTest, were positive for the presence of CTC in 14.2%, 22.8% and 16.5% subjects, respectively. The concordance between the AdnaTest and CK-19 RT-qPCR was 72.4% while between the AdnaTest and multiplex RT-qPCR was 64.6%. In patients with overt metastasis, CK-19 RT-qPCR, multiplex RT-qPCR and the AdnaTest were positive in 41.2%, 39.2% and 54.9% patients, respectively. The concordance between the AdnaTest and CK-19 RT-qPCR was 70.6% while between the AdnaTest and multiplex RT-qPCR was 68.6%.

Conclusions

All CTC assays gave similar results in about 70% of cases. Better agreement was found in the metastatic setting, possibly explained by the higher tumor load in this group. Discordances could be attributed to the different gene transcripts used to evaluate CTC positivity. Our results indicate the importance of CTC heterogeneity for their detection by different analytical methodologies.
Amygdala activation in maltreated children during pre-attentive emotional processing
Authors: McCrory Eamon J. , De Brito Stéphane A. , Kelly Philip A. , Bird Geoffrey , Sebastian Catherine L. , Mechelli Andrea , Samuel Sophie , Viding Essi
Published: March 2013

Background

Childhood adversity is associated with significantly increased risk of psychiatric disorder. To date, functional magnetic resonance imaging (fMRI) studies of children have mainly focused on institutionalisation and investigated conscious processing of affect.

Aims

To investigate neural response to pre-attentively presented affect cues in a community sample of children with documented experiences of maltreatment in the home.

Method

A masked dot-probe paradigm involving pre-attentive presentation of angry, happy and neutral facial expressions was employed. Eighteen maltreated children were compared with 23 carefully matched non-maltreated peers.

Results

Increased neural response was observed in the right amygdala for pre-attentively presented angry and happy faces in maltreated v. non-maltreated children. Level of amygdala activation was negatively associated with age at onset for several abuse subtypes.

Conclusions

Maltreatment is associated with heightened neural response to positive and negative facial affect, even to stimuli outside awareness. This may represent a latent neural risk factor for future psychiatric disorder.
The insulin-like growth factor-system in a patient with diffuse large B-cell non-Hodgkin's lymphoma and lactic acidosis
Authors: Hoogwerf Demelza , van Doorn Jaap , Maartense Eduard
Published: March 2013

Lactic acidosis is a rare complication of haematological malignancies with a poor prognostic outcome and unclear aetiology. Possible mechanisms include high rate of glycolysis by cancer cells, in part due to overexpression of hexokinase II. The insulin-like growth factor (IGF)-system has an important role in normal as well as tumour cell growth. We present a case of a 79-year-old man with a diffuse large B-cell lymphoma and lactic acidosis. Initially, the patient was successfully treated according to the R-CHOP scheme. After recurrence of disease, the patient was treated according to a protocol of the Dutch-Belgian Haemato-Oncology Group (HOVON-85 study). Eleven months after completion of the last therapy, the patient still appeared to be in complete remission. Serum levels of IGFs, pro-IGF-IIE[68-88], IGF binding proteins (IGFBPs)-1 to - 4 , acid labile subunit (ALS), as well as ternary IGF-I-IGFBP-3-ALS complex formation, were determined in samples taken before, during and after treatment, respectively. Before treatment patient's serum concentration of the growth hormone-dependent parameters of the IGF-system and IGF-II were clearly reduced when compared with patient's values during remission of disease. On the other hand, during acidosis a relatively higher proportion of IGFs is present in binary complexes, instead of 150 kDa complexes, that may allow an increased access of IGFs to target cells including the malignant ones. Pretreatment serum levels of IGFBP-1 and -2 were elevated, decreased during therapy and normalized at remission. Especially IGFBP-2 seems a suitable marker for disease activity.
Distinct Expression and Localization of Diacylglycerol Kinase Isozymes in Rat Retina
Authors: Hozumi Yasukazu , Matsui Hirooki , Sakane Fumio , Watanabe Masahiko , Goto Kaoru
Published: March 2013

Recent studies have revealed that phosphoinositide (PI) signaling molecules are expressed in mammalian retinas, suggesting their importance in its signal transduction. We previously showed that diacylglycerol kinase (DGK) isozymes are expressed in distinct patterns in rat retina at the mRNA level. However, little is known about the nature and morphological aspects of DGKs in the retina. For this study, we performed immunohistochemical analyses to investigate in the retina the expression and localization of DGK isozymes at the protein level. Here, we show that both DGKβ and DGKι localize in the outer plexiform layer, within which photoreceptor cells make contact with bipolar and horizontal cells. These isozymes exhibit distinct subcellular localization patterns: DGKι localizes to the synaptic area of bipolar cells in a punctate manner, whereas DGKβ distributes diffusely in the subsynaptic and dendritic regions of bipolar and horizontal cells. However, punctate labeling for DGKϵ is evident in the outer limiting membrane. DGKζ and DGKα localize predominantly to the nucleus of ganglion cells. These findings show distinct expression and localization of DGK isozymes in the retina, suggesting a different role of each isozyme.
Study of bacteria isolated from the foot pad of Spheniscus magellanicus with and without bumblefoot
Authors: Osório L.G. , Xavier M.O. , Ladeira S.R.L. , Silva Filho R.P. , Faria R.O. , Vargas G.D'Á. , Cabana A.L. , Mello J.R.B. , Meireles M.C.A.
Published: March 2013

The bumblefoot or pododermatitis is among the diseases with the highest morbidity in Magellanic penguins, sometimes evolving to septicemia and death. Therefore, this study aimed to relate the main species involved in the disorder, as well as the in vitro susceptibility profile of the microorganisms against routine antimicrobial usage in Veterinary Medicine. During two years in vivo material was harvested from 200 footpads (n=100 animals) for microbiological analysis and in vitro susceptibility tests against the Antibiotic enrofloxacin, streptomycin, penicillin and cephalosporin. Bacteria have been identified both as part of permanent and transient microbiota, also being associated to 100% of the pododermatitis cases. The most prevalent genus were Staphylococcus and Corynebacterium. The antibiograms of all the isolated bacteria resulted in greater susceptibility of the strains facing cephalosporin, followed by enrofloxacin, streptomycin and penicillin.
Implante de condrócitos homólogos em defeitos osteocondrais de cães: padronização da técnica e avaliação histopatológica
Authors: Iamaguti L.S. , Brandão C.V.S. , Mota L.S.L.S. , Ranzani J.J.T. , Ribeiro L.M. , Rossetto V.J.V. , Padovani C.R. , Felisbino S.L.
Published: March 2013

Padronizou-se a metodologia para cultura de condrócitos em cães e avaliou-se seu implante em lesões osteocondrais, utilizando-se a membrana biossintética de celulose (MBC) como revestimento. Dez cães, adultos e clinicamente sadios, foram submetidos à artrotomia das articulações fêmoro-tíbio-patelares. Defeitos de 4mm de diâmetro e profundidade foram induzidos no sulco troclear de ambos os membros. MBC foi aplicada na base e na superfície das lesões. Os defeitos do membro direito foram preenchidos com condrócitos homólogos cultivados formando o grupo-tratado (GT); os do membro esquerdo, sem implante celular, foram designados grupo-controle (GC). A evolução pós-operatória foi analisada com especial interesse nos processos de reparação da lesão, por meio de histomorfometria e imuno-histoquímica para colágeno tipo II e sulfato de condroitina. A cultura de condrócitos homólogos apresentou alta densidade e taxa de viabilidade. Observou-se integridade do tecido neoformado com a cartilagem adjacente na avaliação histológica, em ambos os grupos. Na imuno-histoquímica, verificou-se predomínio de colágeno tipo II no GT. Morfometricamente, não houve diferença significativa entre o tecido fibroso e o fibrocartilaginoso entre os grupos. A cultura de condrócitos homólogos de cães foi exequível. O tecido neoformado apresentou qualidade discretamente superior associado ao implante homólogo de condrócitos, contudo não promoveu reparação por cartilagem hialina.
Diagnóstico clínico e radiográfico de luxação traumática da articulação atlanto-occipital em dois cães
Authors: Araújo B.M. , Figueiredo M.L. , Silva A.C. , Fernandes T.H.T. , Tudury E.A.
Published: March 2013

A luxação da articulação atlanto-occipital é considerada uma afecção incomum no homem e nos animais. Radiografias laterais são recomendadas para o diagnóstico. No entanto, estão sujeitas a erros relacionados ao ângulo de radiação, ao alvo da imagem, à distância e à sobreposição óssea. Objetivou-se neste relato descrever os achados clínicos e radiográficos de dois cães com luxação traumática da articulação atlanto-occipital que apresentavam tetraparesia, dor cervical cranial, incapacidade de elevar a cabeça e déficits de nervos cranianos. No primeiro animal, observaram-se deslocamento craniodorsal do processo articular do atlas em relação a um dos côndilos do occipital, ausência de sobreposição dos forames vertebrais laterais e sobreposição do côndilo do occipital ao processo articular do atlas, no lado direito, caracterizando uma luxação unilateral. No segundo animal, observou-se deslocamento craniodorsal dos processos articulares do atlas em relação aos côndilos do occipital, com sobreposição dos forames vertebrais laterais e ausência de visibilização dos côndilos do occipital em virtude da projeção cranial dos processos articulares do atlas em direção ao crânio, caracterizando luxação bilateral. Conclui-se que o exame radiográfico simples, nas projeções laterolateral e ventrodorsal, apesar da dificuldade de ser interpretado, é eficiente para confirmar o diagnóstico da luxação atlanto-occipital traumática, tanto a simétrica quanto a assimétrica.
Radiografia intraoral e convencional da hemiarcada superior direita de gatos domésticos
Authors: Nepomuceno A.C. , Canola J.C. , Leite C.A.L. , Mesquita L.R. , Silveira T. , Silva F.D.F. , Meirelles A.E.W.B.
Published: March 2013

A proposta com este trabalho foi avaliar a hemiarcada superior direita de gatos domésticos por meio de técnicas radiográficas odontológicas do paralelismo, empregando-se filmes intraorais aos posicionadores de Han Shin. As imagens obtidas por essa metodologia foram correlacionadas com as técnicas radiográficas convencionais (extraorais), com o intuito de se estabelecerem vantagens ou desvantagens para detectar possíveis afecções dentais e periodontais. Foram utilizados 30 gatos, sem raça definida, 17 machos e 13 fêmeas, faixa etária entre um e três anos, confinados em gatis do Departamento de Zootecnia da Universidade Federal de Lavras/MG. Com os animais sob anestesia geral, foram realizadas radiografias da hemiarcada superior direita, incluindo três incisivos, um canino, três pré-molares e um molar em radiografias intraorais e extraorais. As imagens radiográficas foram analisadas e efetuaram-se comparações qualitativas entre pares intraorais e convencionais dos mesmos animais. Para se estabelecer a técnica radiográfica dental mais bem adaptada, foram realizadas análises estatísticas pelo teste de McNemar (qui-quadrado modificado). A técnica intraoral mostrou ser superior à extraoral (P<0,05), para achados referentes a espaço periodontal aumentado, canal radicular amplo e arredondamento de ápice, e também para a avaliação mais bem detalhada de dentes caninos, pré-molares e molares em gatos.
Levedura de cana-de-açúcar spray dry na alimentação de suínos na fase de crescimento e terminação
Authors: Poveda-Parra A.R. , Moreira I. , Furlan A.C. , Oliveira G.C. , Carvalho P.L.O. , Toledo J.B.
Published: March 2013

Foi estudado o valor nutricional (digestibilidade total e ileal) de duas leveduras spray dry (cana-de-açúcar - LEV35 e cerveja+cana-de-açúcar - LEV40) e o efeito da sua inclusão em rações para suínos na fase de crescimento e terminação. Os valores de ED (kcal/kg) da LEV35 e da LEV40 foram 3.496 e 3.901 e EM (kcal/kg) foram 3.475 e 3.862, respectivamente. Os valores de lisina, metionina+cistina e treonina digestível para a levedura de cana-de-açúcar e da levedura de cerveja+cana-de-açúcar são 2,66 e 2,64, 1,11 e 1,03, 1,95 e 1,92, respectivamente. No desempenho foram utilizados 40 suínos com peso inicial de 34,39± 7,57kg (crescimento) e de 62,45± 5,68kg (terminação), distribuídos em delineamento inteiramente casualizado com cinco níveis de inclusão (0, 5, 10, 15 e20%) da LEV35. Na fase de crescimento, houve piora do GDP e da CA com o aumento da inclusão. Na fase de terminação, porém, houve efeito quadrático para o CDR, sendo o melhor nível 3.32%. Da mesma forma, ocorreu piora linear para o GDP, CA, peso de carcaça quente, rendimento de carcaça fria e peso de pernil. Os resultados sugerem que a adição de níveis crescentes da LEV35 pode prejudicar o desempenho dos suínos.
Desempenho de frangos de corte alimentados com dietas contendo diferentes fontes de selênio, zinco e manganês, criados sob condições de estresse térmico
Authors: Boiago M.M. , Borba H. , Souza P.A. , Scatolini A.M. , Ferrari F.B. , Giampietro-Ganeco A.
Published: March 2013

Avaliaram-se o desempenho e o rendimento de carcaça e partes de frangos de corte alimentados com dietas que continham selênio, zinco e manganês complexados ou não a moléculas orgânicas, criados em diferentes temperaturas. Foram utilizados 980 pintinhos machos de um dia de idade, de linhagem comercial, criados durante 42 dias em três câmaras climáticas, que proporcionaram temperaturas alta, termoneutra e baixa. Foi utilizado um delineamento inteiramente ao acaso, em esquema fatorial 3x2+1, sendo três temperaturas de criação, duas fontes de Se, Zn e Mn - inorgânica e orgânica, mais o tratamento testemunha - criação em câmara termoneutra sem adição de Se, Zn e Mn na ração, com sete repetições por tratamento. As aves criadas em condições de estresse térmico apresentaram piores resultados para consumo de ração, ganho de peso e viabilidade, sendo mais sensíveis ao calor do que ao frio. Quando criadas em ambientes quentes, a conversão alimentar foi melhor quando se utilizaram os minerais na forma orgânica. Sob temperatura neutra, as aves não necessitaram da suplementação da dieta com os minerais avaliados.
Características da carcaça e do corpo vazio de bovinos Charolês de diferentes categorias abatidos com similar grau de acabamento
Authors: Pacheco P.S. , Restle J. , Missio R.L. , Menezes L.F.G. , Rosa J.R.P. , Kuss F. , Alves Filho D.C. , Neiva J.N.M. , Donicht P.A.M.M.
Published: March 2013

Avaliaram-se as características de carcaça e do corpo vazio de novilhos (NO), novilhas (NA) e vacas de descarte (VA) Charolês n= 9, 10 e 10, respectivamente, terminados em confinamento e abatidos com similar grau de acabamento. O peso de abate e o peso de corpo vazio (PCVZ) foram similares entre NO, 480,2 e 417,4kg, e VA, 516,2 e 405,8kg, e maiores do que os das NA, 368,3 e 306,1kg. O rendimento de carcaça quente diferiu entre as categorias, sendo 57,2, 53,3 e 50,5%, respectivamente, para NO, NA e VA. Com o rendimento de carcaça quente expresso em relação ao PCVZ, as diferenças entre categorias diminuíram, sendo significativas apenas entre NO e NA. O conteúdo do trato digestivo das VA foi 34 e 45% maior que o dos NO e NA, respectivamente, sendo correlacionado (P<0,05) com peso de abate (r=0,66) e rendimento de carcaça quente (r=-0,41). O peso de carcaça quente foi similar entre NO, 274,9kg, e VA, 260,8kg, e maior que o NA, 196,4kg. O comprimento de carcaça foi maior nas VA, intermediário nos NO e menor nas NA. A área do músculo Longissimus dorsi foi menor nas NA. Novilhos apresentaram melhor conformação de carcaça que as fêmeas, as quais não diferiram entre si.
Relação vitamina E: vitamina C sobre a qualidade da carne de frangos submetidos ao estresse pré-abate
Authors: Fernandes J.I.M. , Sakamoto M.I. , Peiter D.C. , Gottardo E.T. , Tellini C.
Published: March 2013

Determinou-se a melhor relação vitamina E:vitamina C em dietas para frangos de corte, visando ao melhor desempenho produtivo e à melhor qualidade da carne das aves submetidas ao estresse pré-abate. Utilizaram-se 800 pintos de corte, machos, distribuídos em delineamento inteiramente ao acaso, em esquema fatorial 2x4, com dois níveis de suplementação de vitamina E - 0 e 250mg/kg - e quatro de vitamina C - 0, 150, 300 e 450mg/kg. Aos 42 dias de idade, 12 horas ante mortem, amostras de aves de cada tratamento foram submetidas ao estresse por calor e, em seguida, pelo transporte. Foram avaliadas características de desempenho - peso vivo, consumo de ração e conversão alimentar - , bem como rendimento de carcaça e qualidade da carne de peito e coxas - perda de água, cor e pH. Os níveis de vitaminas avaliadas não influenciaram nas características de desempenho avaliadas. Houve menor rendimento de peito (34,2 vs. 34,9%) e maior pH inicial (6,3 vs. 6,1) dos cortes, para aves que sofreram estresse em relação àquelas que não foram submetidas ao estresse pré-abate.
Soft China: o caráter evolutivo da estratégia de charme chinesa
Authors: Duarte Paulo
Published: March 2013

O presente artigo analisa outra vertente (por vezes ignorada ou subestimada) do conceito de poder, o soft power, relacionando-o com o caso concreto de uma potência em ascensão: a China. Inicia-se por definir a noção de soft power, distinguindo-a, para este efeito, dos conceitos de hard power e de smart power. Se, numa primeira fase se recorrerá, sobretudo, à teoria para destacarmos as principais características do soft power, a segunda etapa, essencialmente prática, baseia-se em um estudo de caso: investiga o comportamento da China em matéria de soft power. Desta forma, pretende-se conferir à teoria uma aplicabilidade, sendo ambas duas peças que não se excluem, antes interagem harmoniosamente. Como se concretiza a "ofensiva de charme" chinesa no Sudeste Asiático? Que pontos fortes e pontos fracos tem o soft power chinês? Como se comporta a China perante a questão dos Estados-pária? Como se comporta o soft power chinês no que diz respeito à estratégia marítima da China? Estas e outras questões serão abordadas pelo presente artigo. Na prática, procura-se demonstrar que, ao contrário do passado, o soft power já não é um elemento "estranho" no discurso oficial chinês. Na verdade, a China de hoje parece estar mais preocupada com a imagem que o mundo tem dela.
Poder legislativo e política externa no Brasil: jogando com as regras
Authors: Anastasia Fátima , Mendonça Christopher , Almeida Helga
Published: March 2013

Quais são os cursos de ação que um legislador talentoso, com preferências intensas em alguma área de política externa, seria capaz de identificar no atual arranjo institucional brasileiro, com vistas a ampliar a sua participação no processo decisório relacionado a tal tema? Este artigo toma como objeto o processo decisório relativo à política externa brasileira, dividindo-o, analiticamente, em dois tempos: o primeiro tempo abriga o jogo ex ante do exame das matérias de política externa pelo Poder Legislativo, ou seja, antes de as proposições serem formalmente apresentadas para tramitação e decisão legislativas. No segundo tempo, é jogado o jogo ex post no início da apreciação formal das referidas proposições pelo Poder Legislativo, sejam quais forem os seus autores. Para tanto, foi mobilizado o conceito de heresthetics, de William Riker, significando a capacidade de estruturar o mundo de forma a ganhar o jogo, transformando a situação de desfavorável em favorável para consecução de seus objetivos.
Qualified listening and social management among health professionals
Authors: Raimundo Jader Sebastião , Cadete Matilde Meire Miranda
Published: March 2013

OBJECTIVE: To verify, by means of reports of health professionals, what an institutional program of in-service training must contain that is focused on the development of the capabilities to accomplish qualified listening. METHODS: A study using a qualitative, descriptive method, conducted by means of interviews with a focus on the social representations of six professionals - nurses, psychologists, occupational therapists and managers - of an ambulatory clinic at the Hospital das Clínicas de Belo Horizonte (MG), about the procedures of social management in the use of this tool. For analysis of the obtained results, we used an instrument "Collective Subject Discourse". RESULTS: A qualitative study with a focus on the social representations about the procedures of social management in the utilization of this tool. CONCLUSION: Qualified listening appeared as a management tool to institutionalize transformative work that enables the forwarding of more effective solutions in health care.
The influence of violent TV cartoons watched by school children in Turkey
Authors: Ergün Sibel
Published: March 2013

OBJECTIVE: This study aimed to demonstrate the gender-specific impact of violence-oriented television cartoons on children, and to identify the behaviors demonstrating this influence. METHODS: The research was conducted on a total of 300 students chosen by a simple, random method applying a stratified weight in each school. A 20-question instrument was used for data collection, using face-to-face interviews with the students which occurred during visits to primary schools. RESULTS: A significant gender difference was noted between students' favourite cartoon shows, the type of influence those shows exerted, and the ways in which students imitated the behaviors of the cartoon characters (p<0.05). CONCLUSIONS: It was noted that male children were influenced by violence-oriented cartoons more than female children, and that they imitated cartoon characters more.
Nurse competencies for health promotion in the mental health context
Authors: Aguiar Maria Isis Freire de , Lima Hélder de Pádua , Braga Violante Augusta Batista , Aquino Priscila de Souza , Pinheiro Ana Karina Bezerra , Ximenes Lorena Barbosa
Published: March 2013

OBJECTIVE: To identify the competencies of nurses to health promotion in psychiatric and mental health context. METHODS: Integrative review of literature performed through search using the keywords: "mental health" and "professional competence", in the databases SciELO, LILACS, CINAHL, PubMed, Scopus and Cochrane, in the period of 2003 to 2011. 215 studies were identified, of these, six followed the inclusion criteria. RESULTS: Based on the National Panel for Psychiatric Mental Health NP Competencies, the competencies were identified on the evaluated studies: Monitoring and ensuring the quality of health care practice, management of patient health/illness status, cultural competence, managing and negotiating health care delivery systems, the nurse practitioner-patient relationship. CONCLUSION: The studies analysis evidenced the need for education and training so that nurses may develop the competencies of health promotion in diverse psychiatric care and mental health contexts, in order to broaden knowledge and skills.
On the Performance of the Upstream Mobility Scheme Applied to Counter-Current Two-Phase Flow in a Heterogeneous Porous Medium
Authors: Mykkeltvedt Trine S. , Aavatsmark Ivar , Tveit Svenn
Published: March 2013

The upstream mobility scheme is widely used to solve hyperbolic conservation equations numerically. When heterogeneities in the porous medium are introduced, the flux function in these equations attains a spatial discontinuity. In many systems the upstream mobility scheme approximates a solution close to the solution produced by solving the associated Riemann problem, but in the case of a heterogeneous system there exists no convergence analysis.

In this work the upstream mobility scheme is applied to a counter-current flow in a reservoir where discontinuities in the flux function are introduced through the permeability. Examples of such counter-current flow systems in heterogeneous reservoirs are Water-Alternating-Gas (WAG), Steam-Assisted Gravity Drainage (SAGD) and flow of CO2 and brine. The flux functions in these systems involve both advection and gravity segregation components. In this work we show that the upstream mobility scheme may exhibit large errors compared to the physically relevant solution for some combinations of flux functions in such a system. We show that a small perturbation of the relative permeability values can lead to a large difference in the solution produced by the upstream mobility scheme.

We look at the one-dimensional case since the Riemann solutions are mostly unknown for more than one dimension. However, in the multidimensional case, many numerical methods use one-dimensional calculations for the flux in the direction normal to the boundaries of the discretization cell. Not only does the scheme encounter large errors compared to the physically relevant solution, but the solution also lacks entropy consistency. Studies of these errors and the convergence performance of the scheme are important due to the extensive use of the upstream mobility scheme in the reservoir simulation community.
Adjoint-Based History Matching of Structural Models Using Production and Time-Lapse Seismic Data
Authors: Kahrobaei S.. , van Essen G. M. , Van Doren J. F. , Van den Hof P. M. , Jansen J. D.
Published: March 2013

In spite of large uncertainties in the actual reservoir structure, structural parameters of a reservoir model are usually fixed during history matching and only the flow properties of the model are allowed to vary. This often leads to unlikely or even unfeasible property updates and possibly to a poor predictive capability of the model. In those cases it may be expected that updating of the structural parameters will improve the quality of the history match. Preferably such structural updates should be implemented in the static (geological) model, and not just in the dynamic (flow) model. In this paper we use a gradient-based history matching method to update structural properties of the static model. We use an adjoint method to efficiently compute the derivatives of the data mismatch with respect to grid block porosities in the dynamic model and convert the corresponding volume changes to structural updates (layer thicknesses) in the static model. This method is suitable for structural updating of large scale reservoir models using production data and/or time-lapse seismics or other spatially distributed data. The method is tested on a 3D synthetic model, where time-lapse as well as production data have been used to update depth of the reservoir’s bottom horizon. We obtained significant improvements in the history match quality and the predictive capability of the model.
Advanced Strategies of Forward Simulation for Adjoint-Based Optimization
Authors: Volkov O. , Voskov D. V.
Published: March 2013

Adjoint-based simulation is one of the most efficient methods for reservoir simulation optimization. The gradient information of the objective function and constraints is used to generate a sequence of quadratic programming subproblems converging to the extremum of non-linear problem. The adjoint method provides accurate gradients that help to converge to the optimal solution using the least number of iterations, where each iteration is a forward simulation. The quality and stability of the gradients play important roles in the optimization process. In this paper we present analysis of adjoint-gradients based on different aspects of the forward simulation. We demonstrate that in the presence of compressibility, gradients evaluated using bottom hole pressure (BHP) controls are less consistent with respect to time step refinement, and less stable compared with gradients evaluated using rate controls. Using simple examples, we demonstrate that adjoint-based gradients for rate-controls converge with refinement of the time step while gradients for BHP-controls suffer from convergence problem. Another important aspect of our study is the effect of different nonlinear constraints in the optimization process. In forward simulation, nonlinear constraints often introduce additional complexities due to the discontinuous nature of the switching procedure. Switching can occur at control points in time, or between two controls, and depends strongly on the time-stepping strategy and the truncation error. We compare strategies where individual well constraints are applied directly during the forward simulations and as nonlinear constraints in the optimization process. We demonstrate using two practical examples the advantages and disadvantages of both strategies. We also study the effect of time-truncation error and time-stepping strategy on the quality of the adjoint-gradients. For the time scale, we propose coarsening in both simulation time and redundant control time steps. With larger time steps and smaller numbers of control switches, we can improve efficiency of forward simulation by several fold. Next, the optimal controls of coarse time-step simulation are used as the initial guess for forward simulation of finer time-step resolution. We show how all of these issues affect the optimization of a full-field model.
Advanced Wellbore Simulation of Flow Control Devices With Feedback Control for Thermal Operations
Authors: Stone Terry , Damas Carlos Emilio , Woiceshyn Glenn , Law David Hin-Sum , Brown George , Olapade Peter , Bailey William J.
Published: March 2013

Events such as hydraulic gradients in the horizontal completion, geologic and fluid variations in the reservoir and well placement issues can produce very poor steam conformance in the Steam Assisted Gravity Drainage (SAGD) process. Operators have implemented many strategies in an effort to address the issue. Simultaneous injection in inner tubing and annulus space or dual-tubing completions are commonly used in SAGD wells to provide controllable injection and production from the heel and toe regions of the horizontal well pair but this does not guarantee both uniform and efficient performance. This paper presents a study of a hybrid of two technologies to improve both conformance and economics of this thermal process.

Recent work suggests that using Proportional-Integral-Derivative (PID) feedback to control the steam injection can lead to improvements in SAGD performance and conformance. The feedback control is applied to each steam injection point in the horizontal well pair. Injection at these control points is regulated by a PID feedback controller monitoring temperature differences between injected and produced fluids in order to both enforce a specified subcool and to achieve uniform production along the entire length of the producer. PID feedback control can be practically and inexpensively implemented in the field with current technology.

Inflow or injection control devices (ICDs) can also improve SAGD performance. ICDs (or FCDs) can be incorporated in the horizontal completion as restrictive elements to modify the pressure distribution along the length of the wellbore. Among other benefits, properly sized and distributed ICDs can create a more uniform flow profile along the horizontal section of the well, regardless of permeability, formation damage and wellbore location. Furthermore, ICDs on the producer can provide a self-regulating effect to prevent live steam from entering the sand control screen.

This paper examines detailed wellbore simulations of a SAGD process in which wells are equipped with a combination of ICD completions and feedback control in order to (i) determine the physical mechanisms (including the dynamic flow paths inside the well and in the near wellbore region), and (ii) outline practical procedures to determine an improved ICD completion and feedback control design. A novel aspect of this work is the inclusion of a revised flow-regime-independent multiphase flow correlation that can predict the pressure drop in horizontal and near-horizontal wells. Results presented in this paper should aid reservoir simulation engineers in both the design and optimization of steam injection in a SAGD well pair.
Modeling Multiphase Flow With Nonplanar Fractures
Authors: Al-Hinai Omar , Singh Gurpreet , Pencheva Gergina , Almani Tameem , Wheeler Mary F.
Published: March 2013

Modeling flow with fractures can be challenging due to complex fracture geometries, strong variations in length and time scales as well as the need to combine multiple flow models. In this work, we propose a technique for overcoming these challenges based on the mimetic finite difference method (MFD) and the related multipoint flux mixed finite element method (MFMFE). These discretizations can be employed for solving problems over a set of general polyhedral meshes that can capture nonplanar fracture geometry. Our approach defines a physically and mathematically consistent technique for including internal boundary conditions. In our discretizations, flow in the reservoir and flow in the fracture are coupled using different physical models and numerical schemes. The respective flow models are locally conservative and are based on an implicit pressure/explicit saturation formulation and its iterative form.
A Generalized Framework Model for Simulation of Gas Production in Unconventional Gas Reservoirs
Authors: Wu Yu-Shu , Li Jianfang , Ding Didier , Wang Cong , Di Yuan
Published: March 2013

Unconventional gas resources from tight sand and shale gas reservoirs have received great attention in the past decade around the world, because of their large reserves as well as technical advances in developing these resources. As a result of improved horizontal drilling and hydraulic fracturing technologies, the progresses are being made towards commercial gas production from such reservoirs, as demonstrated in the US. However, understandings and technologies needed for effective development of unconventional reservoirs are far behind the industry needs, e.g., gas recovery rates from those unconventional resources remain very low. There are some efforts in the literature on how to model gas flow in shale gas reservoirs using various approaches from modified commercial simulators to simplified analytical solutions, leading to limited success. Compared with conventional reservoirs, gas flow in ultra-low permeability unconventional reservoirs is subject to more nonlinear, coupled processes, including nonlinear adsorption/desorption, non-Darcy flow (at high flow rate and low flow rate), and strong rock-fluid interaction, and rock deformation within nano-pores or micro-fractures, coexisting with complex flow geometry and multi-scaled heterogeneity. Therefore, quantifying flow in unconventional gas reservoirs has been a significant challenge and traditional REV-based Darcy law, for example, may not be in general applicable.

In this paper, we will discuss a generalized mathematical model and numerical approach for unconventional gas reservoir simulation. We will present a unified framework model able to incorporate all known mechanisms and processes for two-phase gas flow and transport in shale gas or tight gas formations. The model and numerical scheme are based on generalized flow models using unstructured grids. We will discuss the numerical implementation of the mathematical model and show results of our model verification effort. Specifically, we discuss a multi-domain, multi-continuum concept for handling multi-scaled heterogeneity and fractures, i.e., using hybrid modeling approaches to describe different types and scales of fractures from explicitly modeling of hydraulic fractures and fracture network in simulated reservoir volume (SRV) to distributed naturally fractures, microfractures, and tight matrix. We will demonstrate model application to quantify hydraulic fractures and transient flow behavior in shale gas reservoirs.
An Optimization Algorithm Based on Combining Finite-Difference Approximations and Stochastic Gradients
Authors: Yan Xia , Reynolds Albert C.
Published: March 2013

Optimization algorithms that incorporate a stochastic gradient (SPSA, simplex, EnOpt) are easy to implement in conjunction with any reservoir simulator. However, for realistic problems, a stochastic gradient only provides a rough approximation of the true gradient, and, in particular, the angle between a stochastic gradient and the associated true gradient is typically far from zero even though a properly computed stochastic gradient usually represents an uphill direction.

This paper develops a more robust optimization procedure by replacing the largest components in magnitude of the stochastic gradient with a finite-difference approximation of the pertinent partial derivatives. Specifically, after ranking the magnitudes of the components of the stochastic gradient from largest to smallest in magnitude, we replace, in this same order, components of the stochastic gradient with finite difference approximations until we obtain a modified stochastic gradient which is in approximately the same direction as the unknown true gradient. The viability of the method relies on a theoretical result which allows us to approximate the angle between the modified stochastic gradient and the true gradient without knowledge of the true gradient. With this simple procedure, one can continue to replace components of the stochastic gradient with finite different approximations until one obtains a modified stochastic gradient where the angle between it and the unknown true gradient is sufficiently small. As the stochastic gradient is approximate, the n largest component magnitudes of the stochastic gradient do not exactly correspond to the n components of largest magnitude of the true gradient. However, another theoretical result allows us to approximately determine whether a dominant component of the stochastic gradient corresponds to a dominant component of the true gradient. If this correspondence does not hold, one option is to attempt to compute a more accurate stochastic gradient. In essence, the objective of the method is to determine which components of the unknown true gradient are most important and then replace the corresponding components of the stochastic gradient with more accurate finite- difference approximations. This modified gradient can then be used in a gradient-based optimization algorithm to find the minimum or maximum of a given cost function. In this work, we consider only a well known mathematical optimization test problem and published problems on estimating optimal well controls in closed-loop reservoir management although it is clear that the method could also be used for other applications including history matching.
Multiscale Formulations with CVD-MPFA Schemes on Structured and Unstructured Grids
Authors: Parramore Elliot , Edwards Michael G. , Lamine Sadok , Pal Mayur
Published: March 2013

This paper focuses on methods for fine scale modelling and presents development of multiscale methods with particular emphasis on the numerical flux approximation. Families of Darcy-flux approximations have been developed for consistent approximation of the general tensor pressure equation arising from Darcys law together with mass conservation. The schemes are control- volume distributed (CVD) with flow variables and rock properties sharing the same location in a given control-volume and are comprised of a multipoint flux family formulation (CVD-MPFA). The schemes are used to develop a CVD-MPFA based multiscale formulation applicable to both structured and unstructured grids in two-dimensions.
Adaptive-Implicit Strategy for Treating Velocity-Dependent Mobilities in Reservoir Simulation
Authors: de Loubens Romain , Patacchini Leonardo , Moncorgé Arthur
Published: March 2013

In petroleum reservoirs, it is common to assume that the superficial velocity of a fluid phase equals a mobility coefficient (permeability over viscosity) multiplying the opposite of the pressure gradient. Phase mobility is typically a function of phase saturations, compositions, temperature, and to a lesser extent pressure, but in specific circumstances it may also depend on the velocity itself. For example, in polymer flooding the aqueous phase viscosity is velocity-dependent due to non-Newtonian effects.

The numerical treatment of velocity-dependent mobilities in reservoir simulators based on the finite-volumes method is still an unsettled topic. For a fully implicit discretization, the main difficulty lies in the fact that velocities are not necessarily aligned with the grid; therefore the velocity-dependent mobility governing the flux across a cell face is not merely a function of the normal pressure drop. In addition, the implicit relationship between velocity and pressure gradient needs to be inverted for each flux, at each nonlinear iteration. To get around the above difficulties, several commercial or academic simulators implement a semi-implicit scheme where the pressure gradient driving the flow is evaluated implicitly, while the velocity used in mobility calculations is evaluated explicitly based on the previously converged time step. However, a semi-implicit formulation may be subject to stability restrictions.

In this work, we first review the derivation of a linear stability criterion for the two-level semi-implicit discretization of simplified monophasic, non-Newtonian or non-Darcy flow equations. Based on this criterion, we propose an adaptive-implicit strategy where for each individual flux the velocity argument in the mobility function is evaluated either explicitly or implicitly. We discuss the numerical accuracy of this scheme and its benefits in terms of computational cost. Finally, using a specifically designed MATLAB code, we validate our adaptive-implicit strategy on representative 1D and 2D nonlinear test cases.