bluuebunny/crossref_metadata_2025 huggingface dataset:
Reducción de daños en embarazos no deseados y de adicciones no deseadas: una instructiva analogía
Authors: Brewer Colin
Published: March 2016

El tratamiento de las adicciones busca reducir el daño que la adicción causa a los individuos y a la sociedad. Sin embargo, muchos servicios, sobre todo en el sector privado, tienen objeciones ideológicas a la hora de utilizar tratamientos médico-farmacológicos y se muestran críticos con otros servicios que sí ofrecen tratamientos farmacológicos. Esta situación contrasta profundamente con la actitud de las clínicas de planificación familiar (PF), que también buscan reducir daños. Irónicamente, las clínicas más antifarmacológicas suelen ser las que proclaman a toda voz que la adicción es una «enfermedad», mientras que el evitar un embarazo no deseado, que no se considera enfermedad, se aborda y soluciona de forma muy efectiva con técnicas médicas. Las clínicas de PF tienen en cuenta los diferentes modelos de conducta sexual, los contextos sociales y las actitudes de las pacientes cuando diseñan planes de tratamiento individuales, mientras que las clínicas que tratan adicciones parten de un enfoque de talla única o de «lo tomas o lo dejas». Los servicios de adicción pueden aprender lecciones clínicas e ideológicas muy útiles de las clínicas de PF.
Respuesta emocional ante estímulos afectivos en sujetos adictos a opiáceos bajo consumo controlado en el P.E.P.S.A.
Authors: Aguilar de Arcos Francisco , Verdejo García Antonio , López Jiménez Ángeles , Montañez Pareja Matilde , Gómez Juárez Encarnación , Arráez Sánchez Francisco , Pérez García Miguel
Published: March 2016

El objetivo de este estudio es analizar la respuesta emocional ante estímulos visuales afectivos cotidianos no relacionados con las sustancias y su consumo, en dos grupos de sujetos dependientes de opiáceos en situación de consumo prescrito y controlado (heroína y metadona vs metadona), participantes en el P.E.P.S.A. (Programa Experimental de Prescripción de eStupefacientes de Andalucía) tanto entre los dos grupos, como en cada uno de ellos en diferentes fases y también en comparación con un grupo normativo de sujetos no consumidores. Para ello, se usó el I.C.E.R.E., instrumento basado en el I.A.P.S. (International Affective Picture System) y en el S.A.M. (Self- Assessment Manikin) de Peter Lang. Los resultados muestran patrones de respuesta emocional en los sujetos consumidores de opiáceos, en relación a sujetos no consumidores, caracterizados por una menor valoración de los estímulos naturales cotidianos de naturaleza apetitiva y una mayor sensibilidad a los de naturaleza negativa y neutra, muy estables ante diferentes situaciones clínicas y de evolución en el desarrollo del P.E.P.S.A.
Cuestionario de expectativas de resultado de consumo de alcohol (CERCA): propiedades psicométricas en pacientes en tratamiento residencial para las adicciones en México
Authors: Templos-Núñez Liliana , Villalobos-Gallegos Luis , Cervera-Ballesteros Jimena , Marín-Navarrete Rodrigo
Published: March 2016

Las expectativas de resultado de consumo de alcohol son las anticipaciones que una persona hace ante los efectos que el consumo de esta sustancia le provocará. Son útiles al explicar el consumo de alcohol, sin embargo se han evaluado escasamente en población clínica. El objetivo de este trabajo fue desarrollar y evaluar las propiedades psicométricas de una prueba que midiera estas expectativas en mexicanos consumidores de alcohol bajo tratamiento residencial. La versión final de la prueba tiene una alfa de Cronbach alta (0.857) con tres factores con una base teórica que explican un61.5% de la varianza; estas propiedades son superiores a las mostradas por otras pruebas. Para futuros estudios se sugiere incluir un mayor número de mujeres en la muestra a fin de confirmar sus características psicométricas.
Apertura de espacios de consumo higiénico y actuaciones policiales en zonas con fuerte tráfico de drogas. Evaluación mediante el recuento de las jeringas abandonadas en el espacio público
Authors: Vecino Carmen , Villalbí Joan R. , Guitart Anna , Espelt Albert , Bartroli Montserrat , Castellano Yolanda , Brugal Mª Teresa
Published: March 2016

Se analiza la evolución de la inyección de drogas en espacios públicos usando como indicador el recuento del número de jeringuillas retiradas de la vía pública, evaluando además la influencia de las intervenciones sanitarias de reducción de daños y las policiales, mediante un estudio cuasi-experimental antes-después. Para cada intervención se contabilizan las jeringas recogidas mensualmente el semestre anterior y posterior tantoen el distrito implicado como en el conjunto de la ciudad, comparando mediante pruebas U y z la situación con un nivel de confianza del 95%.La media mensual de jeringas recogidas disminuye de 13.132 en 2004a 3.190 en 2012. Comparando los indicadores antes y después de la apertura de espacios de consumo higiénico y de acciones policiales seaprecia que la puesta en marcha de un espacio sanitario para el consumosupervisado de drogas en el casco antiguo se acompaña de una notablereducción de las jeringas abandonadas en la ciudad, y su volumen no varía en el distrito en que está ubicado. La posterior apertura de otro espacio de consumo no comporta cambios significativos en la media de jeringas abandonadas en la zona. Algunas acciones policiales en 2005-06 y 2011 tienen un impacto notable en los indicadores de los distritos en que se producen y del conjunto de la ciudad, mientras que otras no parecen tener el mismo efecto. Los programas de reducción de daños pueden tener un impacto favorable en el consumo de drogas inyectadas en el espacio público y el abandono de jeringas. Algunas intervenciones policiales parecen tener impacto, otras no, y otras un modesto efecto local y temporal.
Adaptación al español de la Substance Dependence Severity Scale: resultados preliminares
Authors: Vélez-Moreno Antonio , González-Saiz Francisco , Ramírez López Juan , Torrico Linares Esperanza , Fernández-Calderón Fermín , J. Rojas Antonio , M. Lozano Óscar
Published: March 2016

La Substance Dependence Severity Scale –SDSS- es una de las pocasescalas que evalúa la dependencia y abuso a sustancias según criteriosDSM en términos dimensionales. Diferentes estudios psicométricoshan aportado evidencias de validez y fiabilidad en su versión inglesa,aunque no se dispone de una versión en español. El objetivo deeste trabajo ha sido describir el proceso de adaptación seguido dela versión inglesa de la SDSS al castellano, y aportar resultadospreliminares sobre su fiabilidad y evidencias de validez.Han participado en el estudio 146 pacientes (79.6% hombres) admitidosa tratamiento en el Centro Provincial de Drogodependencias de Huelvaconsumidores de alcohol, cocaína, heroína y cannabis. Además de laSDSS, se administró la EUROPASI y el Test para la Evaluación de laCalidad de Vida en Adictos a Sustancias Psicoactivas -TECVASP-.La escala de gravedad de la dependencia ha mostrado adecuadaspropiedades psicométricas en términos de sus índices dediscriminación y de consistencia interna (α=0.881 para alcohol;α=0.814 para cocaína; α=0.531 para cannabis; α=0.785 para heroína).En cambio la escala que evalúa el abuso ha mostrado resultados másdeficientes. Sobre las evidencias de validez, las evidencias basadas enla estructura interna han mostrado una estructura unidimensional.Además, las evidencias obtenidas basadas en la relación con otrasvariables apoyan empíricamente las relaciones teóricas postuladas.Los resultados preliminares apoyan el uso de la escala de gravedadde la dependencia. La escala de gravedad que evalúa los criterios deabuso necesita más evidencia empírica para conocer la utilidad de lamisma. Por lo tanto, no es aconsejable su uso según la versión actual.
Craving y abstinencia de la nicotina en fumadores españoles en un tratamiento para dejar de fumar
Authors: Piñeiro Bárbara , López-Durán Ana , López-Durán Ana , Martínez Úrsula , Martínez Úrsula , Brandon Thomas H. , Brandon Thomas H. , Becoña Elisardo
Published: March 2016

El craving y el síndrome de abstinencia de la nicotina (SAN) forman parte del trastorno por consumo del tabaco en el DSM-5. Ambos aparecen tras dejar de fumar o tras una reducción brusca del consumo de tabaco, y están relacionados con los resultados de dejar de fumar a corto y largo plazo. El objetivo del presente estudio fue analizar la relación del craving y del síndrome de abstinencia con dejar de fumar al final del tratamiento y con la recaída a los 3 meses de seguimiento en una muestra de fumadores españoles. La muestra estaba formada por 342 fumadores (37,7% hombres; 62,3% mujeres) que recibieron tratamiento cognitivo-conductual para dejar de fumar. La evaluación del craving y del síndrome de abstinencia se realizó a través de la escala Minnesota Nicotine Withdrawal Scale. Los abstinentes al final del tratamiento, comparados con los no abstinentes, mostraron un síndrome de abstinencia y un craving significativamente menor al finalizar el tratamiento. Además, los abstinentes tenían puntuaciones menores en dependencia de la nicotina antes del tratamiento. Entre los abstinentes, el craving descendió significativamente desde los valores presentados antes de dejar de fumar, mientras que en los participantes que no dejaron de fumar los valores de craving permanecieron en los mismos niveles. La dependencia de la nicotina elevada fue el predictor de fumar al final del tratamiento, mientras que el síndrome de abstinencia de la nicotina elevado fue predictor de la recaída a los 3 meses. Los resultados apoyan el papel robusto del craving y del SAN en dejar de fumar y en la recaída, aunque difieren en sus patrones de cambio a lo largo del tiempo.
Boletín informativo Vol. 26-4
Authors: Socidrogalcohol Socidrogalcohol
Published: March 2016

Boletín
Alcohol consumption, alcohol dependence and related harms in Spain, and the effect of treatment-based interventions on alcohol dependence
Authors: Rehm Jürgen , X. Rehm Maximilien , D. Shield Kevin , Gmel Gerrit , Gual Antoni
Published: March 2016

Alcohol consumption in Spain has traditionally followed the Mediterranean drinking pattern, featuring daily drinking with meals, beer as the preferred beverage, and comparatively little drinking to intoxication. Alcohol depen- dence (AD), one of the most detrimental disorders caused by alcohol, was prevalent in 0.2% of women and 1.2% of men, corresponding to 31,200 women and 186,000 men in Spain with AD in 2005 in the age group of 15 to 64 year. These prevalence estimates of alcohol dependence are likely underestimated due to limitations in the World Mental Health Survey which cannot be fully corrected for; however, the estimates of AD for Spain represent the most accurate and up to date estimates available. Alcohol creates a significant health burden in Spain with 11.3 premature deaths in women per 100,000 aged 15 to 64 years, and 40.9 premature deaths in men per 100,000 in the same age group were due to alcohol consumption (data for 2004). This amounts to 8.4% of all female deaths and 12.3% of all the male deaths in this age group being attributable to alcohol consum-ption. A large percentage of these harms were due to heavy alcohol consumption and AD.AD is undertreated in Spain, with less than 10% of all people with AD trea- ted. For those who are treated, psychotherapy is the most utilized form of treatment to avoid relapse. If 40% of AD patients in Spain were treated with pharmacological treatment (the most effective treatment method), 2.2% of female and 6.2% of male deaths due to AD would be prevented within one year. Thus by increasing treatment rates is an important means of reducing the alcohol-attributable mortality and health burden in Spain.
Addiction to ephedrine in psychiatric disorders
Authors: Martínez-Quintana Efrén , Rodríguez- González Fayna
Published: March 2016

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Unhealthy habits and practice of physical activity in spanish college students: the role of gender, academic profile and living situation
Authors: Molina Antonio J. , Varela Verónica , Fernández Tania , Martín Vicente , Ayán Carlos , Cancela José M.
Published: March 2016

The aim of this study is to identify personal factors associated with drugs use and the practice of physical activity in a college student population in northwest Spain. A cross-sectional survey was conducted between January and April 2010 using a self-administered questionnaire including questions concerning gender, age, course and year of study, living arrangements and work. Participants were asked also about current tobacco use, alcohol drinking and heavy episodic drinking, illegal drugs use, and frequency of physical activity. Prevalences were calculated and bivariate and multivariate logistic regression analyses were conducted to calculate separate models for the different habits making adjustments for the demographic variables. Most of students consumed alcohol (78.3%), with 31.7% consuming tobacco and 34% having used illegal drugs at some point. The prevalence of sufficient physical activity was about 22.7% and it was clearly lower in women and in courses no linked with sports. Women have been lesser consumers of illegal drugs and alcohol. However, heavy episodic drinking is clearly associated with women. Living with friends was noticed as a risk factor, both for tobacco use and the consumption of alcohol and illegal drugs, when compared with living at home. Courses of study connected with sport, health and education showed a lower prevalence of drug uses than the other courses analysed. Since distribution of drug use and insufficient physical activity depending on gender, living arrangement and the course of study, it would be appropriate to design more efficient interventions of health promotion take these differences into account.
Reingreso en prisión de reclusos drogodependientes excarcelados a una comunidad terapéutica, en función de variables previas al tratamiento
Authors: Ramos Barbero Victoria , Carcedo González Rodrigo J.
Published: March 2016

El principal objetivo de este artículo es identificar las variables penales y penitenciarias previas al tratamiento asociadas al reingreso en prisión, en una población de reclusos drogodependientes que fueron excarcelados desde diferentes centros penitenciarios de Castilla y León (España) para sustituir su pena privativa de libertad por el tratamiento en una comunidad terapéutica. La población objeto de estudio fue de 120 internos varones. Las fuentes documentales consultadas para la recogida de información fueron: el protocolo de clasificación y tratamiento, el expediente peni- tenciario y el expediente social. Estos registros oficiales fueron consultados en el Centro Penitenciario de Burgos, responsable de la custodia de los documentos. Aplicando un análisis estadístico descriptivo mediante tablas de contingencia, las variables previas al tratamiento que mostraron mayor asociación con el reingreso en prisión fueron los antecedentes familiares penitenciarios, la condena total superior a cinco años, los ingresos previos a la condena base, la regresión de grado de cumplimiento, la revocación de la libertad condicional, el quebrantamiento de condena, la finalización de la condena en prisión y, muy especialmente, la edad del primer ingreso entre 16 y 21 años. Se confirma mediante un análisis de regresión logística que la variable edad en que los sujetos ingresaron en prisión por primera vez es de vital importancia por el impacto que la prisión puede tener en edades tempranas. Estos resultados ofrecen un perfil del recluso drogode-pendiente que mayor riesgo tiene de hacer un mal uso de la medida alter-nativa a la prisión.
Human enhancement drugs and the pursuit of perfection
Authors: McVeigh Jim , Evans-Brown Michael , Mark A. Bellis
Published: March 2016

The emerging threat to public health posed by the use of human enhancement drugs has remained largely unrecognised. In attempts tobecome stronger, happier or smarter, or to look thinner, younger or morebeautiful, people are turning to a diverse range of pharmaceuticals. Thewidespread availability of drugs with the potential to improve humanattributes, appearance and abilities has generated a new and growingaudience of users. Unlike users of drugs such as heroin, cocaine etc,users of human enhancement drugs do not necessarily perceive themselves as ‘drug users’. Those attracted to these drugs may have little or no knowledge or understanding of the physical or psychological harm associated with these substances or their potential for addiction. In addition to the potent effects of many human enhancement drugs, there are considerable risks associated to the clandestine nature of the market. The growing number of untested, banned or adulterated drugs and the lack of safeguards and quality assurance in the illicit manufacturing process has resulted in serious harms and fatalities. The ease with which pharmaceuticals can be manufactured and distributed, combined with the significant profits that can be made from the illicit market, has resulted in a growing challenge for policy makers and health systems in many countries. This editorial aims to raise awareness of this emerging drugs situation and provide a brief overview of some of the drugs and their associated risks.
Recaídas en la adicción a cocaína: una revisión
Authors: Sánchez-Hervás Emilio , Llorente Del Pozo Juan Miguel
Published: March 2016

Las recaídas siguen siendo un problema común en los trastornos relacionados con el consumo de cocaína. El objetivo de este trabajo es el de revisar los últimos datos de la investigación sobre las variables y factores relacionados con las recaídas en el consumo en personas dependientes a la cocaína. Se realizó una búsqueda electrónica de trabajos que incluyeran el estudio de variables relacionadas con la recaída en el consumo de cocaína, en algunas de las bases de datos nacionales e internacionales más importantes en la actualidad: PubMed, ISI Web of Knowledge, The Cochrane Library, IME e ISOC. Para localizar los últimos datos de investigación la búsqueda se realizó para estudios publicados en el período comprendido entre Enero de 2000 a Julio de 2011. Han sido varios y variados los factores y variables identificadas con cierto poder predictivo, entre los que destacan la problemática psicosocial, los estados emocionales negativos, la ansiedad, la autoeficacia, la comorbilidad psicopatológica, la severidad adictiva, y varias variables relacionadas con el proceso de tratamiento. Los conocimientos sobre los procesos de recaída se han incrementado considerablemente en los últimos años, y aunque la influencia de algunos factores sobre las recaídas en el consumo de cocaína parece clara, la investigación específica es todavía escasa y no concluyente.
Attention, Verbal Learning and Memory deficits in Somatization Disorder: A Pilot study
Authors: Patel Ansha , Kharshiing Korsi Dorene
Published: March 2016

Recent Neuropsychological conceptualization and research evidences suggest deficiencies in information processing, receptive and expressive functions in Somatization Disorder and its plausible association with significant socio-occupational impairment. However, there exists a dearth of literature in exploration of cognitive complains reported by patients with Somatization Disorders. The objective: The present research aimed to carry out a preliminary investigation that assesses, and examines the basic lower cognitive abilities like attention, verbal learning and memory deficits in patients diagnosed with Somatization Disorder versus a group of normal subjects. Method: The study was carried out on 15 male patients diagnosed with Somatization Disorder as per ICD-10 CDDG, aged 20-30 years, in comparison to 15, gender, age, socio economic status, education and background matched normal subjects. The subjects were assessed on tests from The Nimhans Battery (Rao, Subbakrishna, Gopukumar, 2004), The Color Trails Test (D&Elia, Satz, Uchiyama, White, 1996) , The Digit Vigilance Test (Lezak, 1995) , The Triads Test (Nimhans version, 2004), The Auditory Verbal Learning Test (Maj et al., 1994) and The Passages Test (Mukundan, Reddy, Hegde, Jayanthi, Kaliaperumai, 1987). Results: Significant cognitive deficits were found in the Somatization patient group in comparison to control on subdomains of Sustained Attention, Divided Attention, and on all subdomains of auditory verbal list learning and memory. No significant deficits were found on the subdomains of focused Attention and Logical Memory. Conclusion: Evidences of this pilot study suggests that Somatization Disorder is associated with Attention, Verbal Learning and Memory deficits that needs to be investigated elaborately in consideration of function impairments faced by such patients in their day to day lives.
Book publishing activity of scientific and educational institutions in the Republic of Tyva: modern problems
Authors: Oorzhak M. S.
Published: March 2016

This article examines modern trends of the educational and scientific publishing development in the Republic of Tyva. The author uses statistics and unpublished sources provided information on the activity of largest centers in the scientific and educational publishing fields in the republic.
Changes of the paradigm of publications search and use by researchers
Authors: Gureev V. N. , Mazov N. A.
Published: March 2016

The article reviews the most significant changes in searching models and using patterns of readers while working with scientific literature. A shift in the search paradigm and reading models is caused by both common trends of science and technology development, and specific changes in librarianship. Furthermore, an inverse relation is also true, when knowledge on readers’ behavior can be effectively used in acquisition modeling, in providing researchers with scientific information, in revising networks of library access, as well as in improving the editorial policy of academic journals.
The electronic library model to support a «blended learning» system at Novosibirsk State University
Authors: Fedotov A. M. , Vasyuchkova T. S. , Derzho M. A. , Ivancheva N. A. , Fedotova O. A.
Published: March 2016

A technological approach for developing a digital library model to support the blended learning in Novosibirsk State University is considered in the article. The term «digital library» in this work is interpreted as an information management system of structured cataloged collections of interactive training and reference materials. The information system architecture, principles of integration with digital repository and rules of metadata representation and transformation are described. A special emphasis is paid on the activity with key terms dictionaries used for information resources systematization and classification, and modeling relations to the facts.
Information-methodological support on regional library sites
Authors: Rakitskaya L. M.
Published: March 2016

The article is devoted to research of library sites implementing methodological support at the regions. The author analyzes special headings structure, purposes of the regional methodological centers, main directions, forms and methods of library activities. The paper shows efficiency of regional sites and their special headings on different directions of libraries methodological support. A priority is the library staff training and retraining. The model site is proposed, which reveals components and functions of special headings for libraries methodological support.
Interference of freeze-dried Hepatitis A vaccine (H2 strain) on testing bovine serum albumin content by ELISA
Authors: Chen Yueqing , Chen Jun , Chen Zhuo , Zhang Feng , Xia Hualiang , Guan Xinhua , Xin Yajuan
Published: March 2016

Objective To carry on preliminary research on interference effects of freeze-dried attenuated Hepatitis A vaccine（H2 strain）on testing residual Bovine Serum Albumin content by ELISA kit. Methods Interference test was conducted according to Appendix VIII, Chinese Pharmacopoeia (Vol III,2010 edi), and the interference level and its possible resources were explored. Results The protective additives of HAV live vaccine do have certain interference on determining residual BSA content by ELISA kit, among which Cysteine and Glutamic acid might play the leading roles. The general BSA recovery rate is 54% to 85%. We assessed the interference degree by using series of different concentration of single amino acid ingredient: cysteine (0 to 0.2%),glutamic acid(0 to 0.8%). We found BSA recovery rate always higher than 70% with 0 to 2mg/ml (0.2%) cysteine, lower with 0.5 to 2mg/ml than with 0 to 0.5mg/ml and did not differ between 0.5 and 2mg/ml cysteine; And the BSA recovery rates were up to 100% if we applied Glutamic acid (concentration not higher than 0.1%) as an interference. It deserves to be mentioned that the interference effects of Glutamic acid become more stronger along with concentration rising from 0.1% to the peak 0.8%(8mg/ml),the test results showed to be not higher than 2.5ng/ml when we set 20ng/ml BSA standards as a target sample, so that the recovery rate is not more than 12.5%. Conclusion The real value of residual BSA content of HAV vaccine should be reported based on the extent of interference. Here when the result appeared to be negative by ELISA we would report as <2.5 ng/ml and as < 5ng/ml if the testing value showed between 0 and 3ng/ml. And what we have done might be a reference to the other enterprises on optimizing the protocol for cryopreservation or evaluating the residual BSA content results.
Progress on the Virus In vitro Diagnose and Reference Materials
Authors: Wang Feifei , Shi Dawei
Published: March 2016

   The pathogen diagnosis of viral disease has become one of the important branche of the virology research, and there are mainly two kinds of methods about viral disease diagnosis, those based on nucleic acid and protein based at present. Reference materials are the key in the viral diagnostic test. The paper reviews the related literatures, regulations and laws as well as the managements of World Health Organization and China.
African Green Monkey Embryonic Stem Cell - a Better Host of Rabies Vaccine
Authors: S Jagannathan , R Vijayakumar , Gandhi P Rahul , Devi T Uma , S Sathiyavimal , S Vasantharaj
Published: March 2016

Rabies, an invariably fatal viral disease is transmitted to humans through animal bites, most commonly dogs. The disease is preventable through timely pre-and post-exposure vaccination. However, once the disease occurs, death is inevitable. More than 1.4 billion people are at potential risk of rabies infection in the South-East Asia (SEA) Region, each year around 24 000 people die in the SEA Region due to rabies which accounts for approximately 45% due to rabies worldwide. Vaccines against rabies virus are currently produced in vero cells, chick embryo, duck embryo and human diploid cell lines which are not meeting the demand for rabies vaccines increasing every year. This review portrays the potential and importance of embryonic stem cells as promising host for the production of rabies vaccines. The advantages of using stem cells and its characters have been reviewed with significant references.
Multifunctional viral protein R of human immunodeficiency virus-1 as a potential drug target
Authors: Darapaneni Vivek
Published: March 2016

The viral protein R (Vpr) plays a pivotal role in the infectious lifecycle of human immunodeficiency virus-1. The objective of this study is to find the degree of conservation of Vpr and to detect conserved binding sites, which might be used as target sites for potential anti-Vpr drugs. The conservation analysis was based on 5301 amino acid sequences identified novel conserved and highly conserved sites.  The novel conserved sites which have been identified are: Leu42, Gly43 and Val57; Arg73 and Cys76; Glu24, His33, Cys76 and Ser79. The outcome of this study provide the foundation for developing anti-Vpr drugs which have abridged potential to induce drug resistance through mutations.
Possibility of Flooding Polymer or Water Reuse via Innovative Selective or Total Flocculation of Enhanced Oil Recovery Produced Water
Authors: Aften Carl W. , Zhang Yanqi Joy
Published: March 2016

Research has discovered systems that can selectively flocculate mineral solids from a high molecular weight polymer flood matrix while leaving the polymer intact or alternatively achieving a viable total flocculation of the polymer in the produced fluids. Modified alkaline surfactant polymer (ASP) and standard polymer (P) flood systems were studied with findings obtained by controlled variations of both well-proven and non-prevalent chemical approaches. Results concluded that selectively removing the mineral solids from polymer-laden water produces reusable enhanced oil recovery (EOR) fluid.

EOR is a proven method to increase hydrocarbon yield from post-natural, stimulated, or standard flood driven reservoirs. Fluid produced from the reservoir contains the desired hydrocarbon and an aqueous phase. Previously considered a liability, properly treated, the aqueous phase can become an asset. Polymer floods have a proven history in EOR and, though complex in application, ASP also demonstrated EOR effectiveness in the laboratory. Most ASP approaches are currently in field trial stages. The produced fluid is subjected to hydrocarbon separation with the resulting aqueous system either treated for disposal or recycled into the system. The aqueous phase matrix is mainly composed of high molecular weight polymer, mineral solids, residual base, residual oil, and possibly surfactant. If the producer chooses disposal, the solids must be flocculated by a method balancing density, dewaterability, processability, process variability, and cost. However, if the producer opts to recycle the fluid for reinjection, steps must be taken to minimize polymer deviations requiring selective flocculation of all components with exception of the polymer. This undertaking is challenging as EOR polymers are also effective flocculants, therefore sensitive to standard coagulant and flocculant approaches. Utilizing controlled, standard methods and multivariable design of experiments, results were obtained for both total and selective flocculation.

Total flocculation systematically studies the influence of pH, inorganic, and organic coagulants in maximizing the treatment effectiveness. The same approach was successful for selective flocculation, however unique coagulants were applied. The selective flocculation process coagulated and separated the mineral solids, and left the high molecular weight polymer intact and the fluid matrix as viscous as prior to treatment. Effectiveness of treatments were determined using standard gravimetric and viscometric methods.

These discoveries will assist decision makers in determining whether total or selective flocculation is the most viable treatment for polymer based EOR, balancing environmental and economic aspects to pursue a desired treatment route. These methods, though targeting EOR, have practical applications for treatment of flowback and water produced from stimulation and potentially drilling operations as well.
Experimental Study on Calculating Capillary Pressure from Resistivity
Authors: Hou Binchi , Liu Hongliang , Bian Huiyuan , Wang Chengrong , Xie Ronghua , Li Kewen
Published: March 2016

Capillary pressure and resistivity in porous rocks are both functions of wetting phase saturation. Theoretically, there should be a relationship between the two parameters. However, few studies have been made regarding this issue. Capillary pressure may be neglected in high permeability reservoirs but not in low permeability reservoirs. It is more difficult to measure capillary pressure than resistivity. It would be useful to infer capillary pressure from resistivity well logging data if a reliable relationship between capillary pressure and resistivity can be found. To confirm the previous study of a power law correlation between capillary pressure and resistivity index and develop a mathematical model with a better accuracy, a series of experiments for simultaneously measuring gas-water capillary pressure and resistivity data at a room temperature in 16 core samples from 2 wells in an oil reservoir were conducted. The permeability of the core samples ranged from 9 to 974 md. The gas-water capillary pressure data were measured with confining pressures using a semi-porous plate technique. We developed the specific experimental apparatus to measure gas-water capillary pressure and resistivity simultaneously. The results demonstrated that the previous power law model correlating capillary pressure and resistivity works well in many cases studied. A more general relationship between the exponent of the power law model and the rock permeability was developed and verified using the experimental data.
Relative Permeability Estimation in Steam Assisted Gravity Drainage (SAGD) Using a Fractional Flow Model
Authors: Morte M. , Hascakir B.
Published: March 2016

Enhanced oil displacement in a reservoir is highly affected by wettability alterations in conjunction with the lowering of viscosities during steam assisted gravity drainage (SAGD) for bitumen extraction. The impartation of energy in the form of heat to the fluid by injecting steam triggers an alteration to a more water-wet state during SAGD. However, the presence of three distinct phases in the reservoir has implications for the effective modeling of the complex fluid dynamics. Dependency of the relative permeability endpoints on the temperature realized as a function of the introduction of steam is difficult to model. Optimization of any steam process requires simulation in order to adequately characterize years of flow and so a model that is capable of representing three phase flow is necessary. To obtain this a pseudo-two phase relative permeability is proposed that assumes fractional flow theory is valid and treats the experiments as a waterflood.

In this study, experimental recovery data for two SAGD experiments and one hot water flood are empirically matched by manipulating relative permeabilities. The analytical approach implemented allows for the representation of fluid flow in the reservoir by achieving a pseudo-two phase relative permeability that results in comparable performance to the experiments. Waterflooding techniques were utilized which allowed for the negation of the steam phase in the model and so two-phase flow was established.

The sensitivity of the relative permeability curves to temperature change results in the inability to formulate a generic three-phase curve and so the pseudo-two phase curve is valuable for the purpose of simulation. The methodology presented enables the formulation of a simplified relative permeability that is unique to each process used and in that specific location. The model that was established was validated and proven credible by the good match with the experimentally obtained values.
A New Microfluidic Tensiometer for Optimizing EOR Formulations
Authors: Moiré M. , Peysson Y. , Pannacci N. , Herzhaft B. , Colin A. , Dalmazzone C.
Published: March 2016

In the case of surfactant EOR, an optimum formulation of surfactant has to be injected in the reservoir. This so-called optimum formulation corresponds to a minimum in the interfacial tension and a maximum in oil recovery and may be obtained with an appropriate balance of the hydrophobic and hydrophilic affinities of the surfactant. Salinity—scan tests are generally used to screen phase behavior of surfactant formulations before conducting time-consuming coreflood tests. The objective of this study was to develop a high-throughput dynamic microfluidic tensiometer, with the aim of studying interfacial phenomena between EOR injected formulations and crude oils and of optimizing chemical EOR processes for pilot or field applications.

We have selected a method based on the Rayleigh-Plateau instability and the analysis of the droplets to jetting transition in a coaxial flow of two fluids. In fact, in coaxial flows, the transition between a droplet and a jetting regime depends on the velocities of each phase, the viscosity ratio, the confinement and the interfacial tension (IFT). As the three first parameters are known, the dynamic interfacial tension can be calculated. This microfluidic device has been specifically designed to support high temperatures (up to 150°C), high pressures (up to 150 bars) and is compatible with complex fluids such as crude oils and solutions of surfactants and polymers.

The method was first developed and validated on a microfluidic device on model fluids at ambient temperature and atmospheric pressure for IFTs higher than 1 mN/m. It was then successfully applied for the measurement of IFTs over more than four decades. Measurements were also performed with a crude oil and a typical surfactant formulation. The validation of the HP/HT assembly, which has been designed with the aim to work in reservoir conditions, is currently under progress. By using this tensiometer, it would be quite easy to perform in short time numerous salinity scans on real systems in order to get the evolution of IFT and determine the optimal salinity S*.
Improved Bitumen Recovery from Mined Oil Sand Ore Using Colloidal Nanosilica
Authors: Kuznetsov Oleksandr , Mazyar Oleg , Agrawal Devesh , Suresh Radhika , Feng Xianhua , Behles Jackie , Khabashesku Valery
Published: March 2016

Oil sand ore flotation is a primary method of bitumen recovery from mined Athabasca tar sands. In bitumen flotation, suspended biwettable ore fines, such as clays, tend to migrate to oil-water interfaces, creating slime coating on liberated bitumen droplets. Slime coating significantly reduces the efficiency of the flotation process and overall oil recovery. Ultra-dispersed hydrophilic silica nanoparticles were found to stabilize biwettable ore fines in an aqueous phase by adsorbing onto fines surfaces, even at concentrations as low as 50 ppm. As a result, fine solids move away from oil/water interfaces, reducing the slime coating and increasing bitumen recovery during flotation of low-grade ore by more than 5%. The addition of nanoparticles has no negative effect on froth quality or oil, water and solid separation in naphthenic and paraffinic froth treatment processes. Detailed molecular dynamics (MD) simulations revealed mechanisms that improve bitumen liberation from mined oil sands in a flotation process. The studies demonstrated that colloidal nanoparticles affect many stages of the bitumen extraction process from bitumen separation to clay wettability alteration.
Single Well Tracer Test Results in a High Temperature, High Salinity Offshore Carbonate Reservoir for Chemical EOR Pilot Evaluation
Authors: Bursaux Romain , Peltier Sophie , Nguyen Michel , Romero Carolina , Morel Danielle
Published: March 2016

In 2014, TOTAL performed two Single Well Tracer Tests (SWTT) to evaluate the remaining oil saturation in an offshore high temperature, high salinity carbonate reservoir. The SWTT method has proved to be a reliable way, when carefully programmed, to measure a representative remaining oil saturation without being impacted by near wellbore effects. The objective of these measurements was to evaluate the efficiency of a single well chemical EOR (CEOR) pilot by measuring oil desaturation.

Extensive in-house laboratory work was carried out by TOTAL to lay the foundation for the pre and post CEOR pilot SWTTs. A specific tracer injection skid was internally developed to ease the operations. Specific numerical work was performed to achieve robust designs and interpretations. These simulations, carried out in-house, took into account all major uncertainties highlighted by experimental work. Detailed results from the SWTT preparation phase will be described in the paper.

Results from the baseline SWTT interpretation evidenced excellent quality tracer profiles from the first test and high remaining oil saturation, improving our knowledge on the flooding pattern of this reservoir. Results from the post EOR SWTT showed again a clear response of a remarkable decrease in remaining oil saturation, proving the efficiency of the chemical formulation provided by TOTAL and the envisaged recovery mechanism. Interpretation of these Single Well Tracer Tests also allowed us to evidence a much lower than anticipated reservoir dispersion. These findings highlight the potential of EOR implementations in these carbonate formations.

Lessons learned from these two offshore SWTTs are discussed in this paper, such as the need for specific preparation to tackle the complexity of a high temperature high salinity carbonate reservoir in presence of H2S. TOTAL has shown that such operations can be performed in a strict timeframe while adhering to company safety rules. Careful interpretation of such results is mandatory to validate the success of the single well chemical EOR pilot.
Optimization of Production and CO2 Utilization Via Parametric Representation and Evaluation of WAG Schedules
Authors: Klenner Robert , Gao Panqing , Taghizadeh Okhtay , Iyer Naresh , Azzaro Steven , Murrell Glen
Published: March 2016

Given limited CO2 supply, operational constraints, and pattern specific reservoir performance, WAG schedule can be customized such that NPV or other metrics are optimized. Depending on the WAG schedule, recovery can fluctuate between 5–15% at the pattern scale due to reservoir heterogeneity causing variations in sweep efficiency. An analytical method was developed to optimize WAG schedules that couples traditional reservoir modeling and simulation with machine learning, enabling the discovery of optimal WAG schedules that increase recovery at the pattern level. A history-matched reservoir model of Chaparral Energy's Farnsworth Field, Ochiltree County, TX was sampled intelligently to perform predictive reservoir flow simulations and artificially build an intelligent reservoir model that samples a broad range of possible WAG scenarios for optimization. The intelligent model generates the next "best" sample to investigate in the numerical simulator and converges on the optima, quickly reducing the number of runs investigated. Results in this paper demonstrate that there can be significant improvements in net present value as well as net utilization rates of CO2 using this analytical technique. The WAG design generated by the intelligent reservoir model should be deployed in the field in early 2016 for validation. It is intended that the intelligent reservoir model will be updated on a regular basis as injection and production data is obtained. This effort represents the beginning of a paradigm shift in the application of modeling and simulation tools for significant improvements in field production operations.
Design of an ASP Pilot for Caracara Sur Oilfield: Selection of Chemicals and Laboratory Assessment
Authors: Prieto C. A. , Rodriguez R. , Romero P. , Blin N. , Panadero A. , Escudero M. J. , Barrio I. , Alvarez E. , Montes J. , Angulo R. , Cubillos H.
Published: March 2016

The design of an alkali-surfactant-polymer (ASP) formulation for chemical Enhanced Oil Recovery poses multiple challenges from the experimental point of view. The present research examines the laboratory procedures and experimental results aimed at selecting the most suitable chemicals for an ASP pilot trial at the Caracara Sur field (Los Llanos Basin, Colombia). The key challenge was the limited compatibility of the surfactant and polymer selected under reservoir conditions (temperature and total salinity), leading to phase separation of the ASP solution and losses of the activity of both chemicals. An extension of the experimental program was required to re-design the formulation and mitigate risks of damaging the formation in the following field trials. The formulation comprised an alkyl benzene sulfonate as main ingredient, a hydrolyzed polyacrylamide as viscosifying agent and some weak alkali to reach the optimum salinity of the mixture. A mono-alkyl diphenyl disulfonate ether was added as coupling agent to improve compatibility of the ASP mixture. The performance of the selected ASP formulation was assessed by means of interfacial tension measurements, long-term thermal stability tests and dynamic core-flooding tests. The formulation provided ultra-low interfacial tension (< 10-2 mN/m) and viscosity enough to assure an appropriate mobility control. Hence, the formulation was considered to be suitable for further testing in the field pilot.
Foams with Wettability Alteration for Oil-Wet Carbonate Rocks
Authors: Ghosh Pinaki , Mohanty Kishore K.
Published: March 2016

Carbonate rocks are typically heterogeneous at many scales; hence foams have the potential to improve both oil displacement efficiency and sweep efficiency in carbonate rocks. However, foams have to overcome two adverse conditions in carbonates: oil-wettability and low permeability. This study evaluates several foam formulations that combine wettability alteration and foaming in low permeability oil-wet carbonate cores. Contact angle experiments were performed on oil-wet calcite plates to evaluate the wettability altering capabilities of the surfactant formulations. Static foam stability tests were conducted to evaluate their foaming performance in bulk. Finally, oil displacement experiments were performed using Texas Cream and Estaillades Limestone cores with crude oil. Two different injection strategies were studied in this work: alternating gas-surfactant-gas injection and co-injection of wettability alteration surfactant with gas at a constant foam quality. Cationic surfactants DTAB and BTC altered the wettability of the oil-wet calcite plate to water-wet, but were ineffective in forming foam. The addition of a non-ionic surfactant Tergitol NP helped in the foaming ability of these formulations. In-house developed Gemini cationic surfactant GC 580 was able to alter the wettability from oil-wet to water-wet and also formed strong bulk foam. Static foam tests showed increase in bulk foam stability with the addition of zwitterionic surfactants to GC 580. Oil displacement experiments in oil-wet carbonate cores revealed that tertiary oil-recovery with injection of a wettability-altering surfactant can recover a significant amount of oil (about 20–25% OOIP) over the secondary water flood and gas flood. The foam rheology in the presence of oil suggested propagation of only weak foam in oil-wet low permeability carbonate cores.
Identifying and Evaluating Surfactant Additives to Reduce Water Blocks after Hydraulic Fracturing for Low Permeability Reservoirs
Authors: Liang Tianbo , Achour Sofiane H. , Longoria Rafael A. , DiCarlo David A. , Nguyen Quoc P.
Published: March 2016

Significant amount of fracturing fluid is lost after hydraulic fracturing, and it is believed that the loss of fluid into the matrix can hinder the hydrocarbon production. One way to reduce this damage is to use the surfactants. Robust surfactant formulations have been developed for chemical enhanced oil recovery (CEOR); similar ideas are introduced in this study to reduce water blocks in low permeability reservoirs. Here we present an experimental investigation based on a coreflood sequence that simulates fluid invasion, flowback, and hydrocarbon production within the rock near the fracture face. Different levels of IFT reductions are tested and compared in order to explore the best condition that maximizes the permeability enhancement. The effect of in-situ microemulsion generation to mobilize the trapped water is also studied. From this work, we recognize the mechanism responsible for the permeability damage in matrix and we suggest criteria to optimize the performance of surfactant additives so as to enhance the hydrocarbon production from low permeability gas/oil reservoirs after hydraulic fracturing.