bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efecto de la terapia antiretroviral de gran actividad (TARGA) en pacientes enrolados en un hospital público en Lima-Perú.
Authors: Echevarría Zárate Juan , López de Castilla Koster Diego , Iglesias Quilca David , Seas Ramos Carlos , González Lagos Elsa , Maldonado Costa Fernando , Maguiña Vargas Ciro , Verdonck Bosteels Kristien , Gotuzzo Herencia Eduardo 
Published: March 2016

Introducción: En mayo del 2004, el Ministerio de Salud (MINSA) en colaboración con el Fondo Global de lucha contra el SIDA, la tuberculosis y la malaria implementó el programa nacional (PN) para brindar terapia antiretroviral en forma gratuita a todos los pacientes infectados con el VIH con indicación de tratamiento de acuerdo a la guía del PN. Objetivos: Describir las características pre-tratamiento antiretroviral, respuesta a la terapia antiretroviral de gran actividad (TARGA), toxicidad y tasa de mortalidad de la población de pacientes que iniciaron TARGA a través del PN en un hospital general. Material y Métodos: Revisamos las historias clínicas, fichas médicas, resultados de laboratorio y tarjetas de TARGA de todos los pacientes enrolados en el PN en el Hospital Nacional Cayetano Heredia (HNCH) y describimos las características pre-tratamiento antiretroviral, respuesta a la TARGA, toxicidad y tasa de mortalidad. Los pacientes seleccionados para este estudio fueron sujetos infectados con el VIH que: (i) tenían 18 años o más; (ii) iniciaron TARGA en el PN entre mayo 2004 y abril 2006; y (iii) no habían recibido terapia antiretroviral anteriormente (naïve). Se consideró como éxito virológico a la presencia de por lo menos un valor de carga viral indetectable (VIH-1 ARN < 400 copias/mL) entre los 3-6 meses posteriores al inicio de la TARGA. Resultados: Se incluyeron en el estudio a 453 pacientes: 68% fueron varones, la edad promedio fue 35,7 ± 9,5 años y el peso fue 55,6 ± 10,8 Kg. El valor medio de CD4 pre-tratamiento fue 98 células/mm3 y el de carga viral fue 278 438 VIH-1 ARN copias/mL. Descontinuaron el tratamiento 84 pacientes (22 abandonaron, 59 fallecieron y 3 fueron transferidos a otra institución). Aquellos que continuaron fueron seguidos en promedio 337 días; el 38% (142/369) interrumpió temporalmente la TARGA, principalmente debido a toxicidad medicamentosa (82%). Se obtuvo éxito virológico en 85% de los pacientes. La mortalidad fue 13% y el 74% de las muertes ocurrió antes de los 3 meses de tratamiento. Conclusión: A pesar de una elevada frecuencia de interrupción del tratamiento, nuestros resultados muestran que la respuesta a las medicinas distribuidas por el PN es comparable a la reportada por programas de otros países. Es necesario realizar más estudios que evalúen la respuesta al tratamiento antiretroviral a largo plazo en el Perú.
Osteosíntesis con placa puente en fracturas diafisiarias conminutas de húmero.
Authors: Mancilla Mancilla Luis 
Published: March 2016

Objetivo: Describir y evaluar la técnica de osteosíntesis percutánea mínimamente invasiva en fracturas disfisiarias conminutas de húmero. Material y Métodos: Estudio descriptivo longitudinal de tres pacientes con diagnóstico de fractura de húmero clasificación AO 12C3 tratado quirúrgicamente en el Hospital Nacional Cayetano Heredia, evaluándose pérdida sanguínea intraoperatoria, tiempo quirúrgico, movilidad de articulaciones vecinas y callo óseo. Resultados: La perdida promedio de sangre fue de 180cc y el tiempo operatorio promedio 60 minutos. Los pacientes presentaron dolor leve tolerable desde el primer día post operatorio, movilidad del hombro y del codo sin limitación, formación del callo óseo a partir de la cuarta semana y consolidación ósea a las 12 semanas promedio. No hubo lesión del nervio radial. Conclusiones: La placa puente es una alternativa de tratamiento en fracturas conminutas diafisiarias del húmero tanto por su bajo costo como por la rehabilitación funcional precoz de las articulaciones vecinas, asimismo recomendamos la visualización intra operatoria del nervio radial.
Consumo de alcohol y autoinforme de eventos violentos en Chile
Authors: Castillo-Carniglia Álvaro , Pizarro Esteban , Luengo Daniela , Soto-Brandt Gonzalo 
Published: March 2016

Se estudió la asociación entre el consumo intenso y la frecuencia mensual de alcohol con el autoinforme de episodios de violencia cometido por personas bajo los efectos del alcohol u otras drogas. Se realizó un estudio transversal en el que se analizaron los datos del Estudio Nacional de Drogas en Población General de Chile del año 2010. La muestra encuestada fue de 16.000 sujetos de 12 a 64 años de edad (media de 35,8 años), que representan a una población de 9.536.602 personas (49,5% de hombres y 50,5% de mujeres). Las variables dependientes fueron: haber sido víctima de asalto, agresión o violencia sexual. Las variables independientes fueron: el consumo intenso (seis o más consumiciones en una ocasión al menos una vez en el mes) y la frecuencia mensual de consumo de alcohol. La razón de prevalencia (RP) ajustada en hombres que informan consumo intenso (vs. informes negativos) fue de 1,85 (IC95%: 1,28 a 2,66) para asalto, 2,0 (1,40 a 2,73) para agresión y 1,35 (0,43 a 4,23) para violencia sexual. En mujeres, las RP fueron 2,08 (0,97 a 4,50), 1,61 (0,78 a 3,35) y 1,37 (0,48 a 3,91), respectivamente. En relación a la frecuencia de uso de alcohol, por cada día de consumo al mes la RP aumenta significativamente para agresión en hombres y para las tres variables de victimización en mujeres. Los hombres y mujeres que informaron un consumo frecuente y/o intenso de alcohol presentaron prevalencias significativamente mayores de episodios de agresión, asalto o violencia sexual, respecto a aquellos que no informaron estos patrones de consumo.
Relación entre la comorbilidad psicopatológica y las variables de resultados en dependientes de cocaína tratados en comunidad terapéutica
Authors: Vergara-Moragues Esperanza , González-Saiz Francisco , Lozano-Rojas Oscar , Fernández Calderón Fermín , Verdejo García Antonio , Betanzos Espinosa Patricia , Bilbao Acedos Izaskun , Pérez García Miguel 
Published: March 2016

El ingreso en comunidad terapéutica de personas con problemas de consumo de cocaína y comorbilidad psicopatológica ha ido aumentando en los últimos años y es importante conocer más sobre el éxito de estos tratamientos. El objetivo de este trabajo es estudiar el perfil psicopatológico de los pacientes dependientes de cocaína y su asociación con las variables de resultados. Se entrevistaron mediante la Psychiatric Research Interview for Substance and Mental Disorders (PRISM-IV) y la Conners’ Adult ADHD Diagnostic Interview for DSM-IV (CAADID) a una muestral total de 218 pacientes que solicitaron tratamiento en alguna de las seis comunidades terapéuticas públicas de Andalucía. Los resultados exponen que el porcentaje de retención a los tres meses es del 68.3% (149). De los cuales, el 43.5% abandona el recurso con un alta terapéutica y el 52.8 % con cambios clínicamente relevantes. Además, el 57.8% presentan comorbilidad psicopatológica. Por último, existe un mayor éxito terapéutico (medidos por días de estancias, tipo de altas y objetivos cumplido tras el tratamiento) entre las personas sin comorbilidad psicopatológica. Estos datos sugieren la necesidad de adaptar las comunidades terapéuticas en el tratamiento de personas dependientes de cocaína con comorbilidad psicopatológica y, de esta manera, mejorar el éxito terapéutico.
Neurotoxicity of Japanese encephalitis Virus chimeric with dengue type 2 virus strain on sucking mice
Authors: Wei Yan , Wang Shiwen , Zhang Quanfu , Miao Fang , Wang Xiaofang 
Published: March 2016

<p>The aim is to indentify the safety of JE/DV2 chimeric virus by neurovirulence experiment with sucking mice. <strong> </strong>Chimeric viruses, DV2 and JEV were diluted. TCID50 of diluted virus liquid were from 10<sup>-5</sup>to 10<sup>-1</sup>. Sucking mice were injected intracerebrally with every type of viruses at each dose level and then were observed for 14 days. Survival curve were compared between different groups by Log-rank test. The results showed that survival rate of the sucking mice in two chimeric virus groups were lower than those of JEV group (p&lt;0.05). Compared with DV2 group, survival rate of the sucking mice in two chimeric virus groups were lower than those of DV2 group (p&lt;0.05) in some levels of dose. However, in some levels of dose there were no statistical significance between the chimeric virus group and DV2 group. Results of sucking mice experiment about neurotoxicity indicated that the rescued chimeric virus was not attenuated.</p>
A Comprehensive Approach to Assess Remaining Oil Saturation and Sweep Efficiency in a Large Carbonate Reservoir
Authors: Al-Anazi Amer M. , Al-Zahrani Tareq M. , Abdulmohsin Mustafa I. 
Published: March 2016

Abstract
Accurate assessment of remaining oil saturation and sweep efficiency greatly depends on the implemented monitoring program, which requires the integration of all available geoscience and engineering data, by effective analysis using statistical and reservoir simulation methods. This will allow improvedunderstanding of sweep, validation of recovery factor and identifying new development opportunities.
Comprehensive reservoir surveillance is also a critical factor for effective reservoir management in achieving optimal hydrocarbon recovery. Monitoring programs encompass the deployment of up-to-date reservoir saturation tools and techniques capable of delivering high-quality data. There are many complications to be considered such as mixed salinity environments, reservoir heterogeneities, tools with limited depth of investigation and mud invasion effects. These challenges must be considered for a successful reservoir saturation monitoring program. Therefore, the value established by an integrated program involves the use of the most efficient approach in analyzing the acquired saturation data and overcoming the field challenges.
This paper presents a comprehensive approach that was implemented on in situ data acquired from a carbonate reservoir that has operated continuously for several decades with pressure support from peripheral water injection. The technique capitalizes on the wealth of data acquired both from saturation and production logs. The prime objectives of this technique are to evaluate remaining oil saturation, remaining unswept oil column and displacement, and vertical/areal sweep efficiency. The strength of this methodology is the capability of efficiently quantifying and mapping remaining oil saturation. This helps in identifying "sweet spots" behind the flood front and thereby guiding future development activities for maximizing hydrocarbon recovery.
The Myths of Waterfloods, EOR Floods and How to Optimize Real Injection Schemes
Authors: Baker Richard , Dieva Rous , Jobling Robert , Lok Crystal 
Published: March 2016

Abstract
Waterflood implementation accounts for more than half of the oil production worldwide. Despite the observations and extensive research from a large number of floods and thousands of simulation studies, managing waterfloods and Enhanced Oil Recovery (EOR) floods is still a technical challenge. A major contributor to this challenge are waterflood induced fractures (WIF). Managing waterfloods is a multivariable problem although WIF are one aspect, it is by no means the only controlling factor.
The best evidence that WIF are one of the main factors controlling flow in reservoirs is the insensitivity of injection pressure to injection rates. With our experience, in hundreds of waterfloods, we have frequently observed this phenomenon in the field data. If fluid flow depended on diffusive Darcy flow alone, we would expect higher injection rates with higher injection pressures. However, it is common to observed relatively constant injection pressures over a wide range of water injection rates. Rapid well communication and changes in water cuts that vary with injection rates also support an interpretation of high permeability induced fractures between injector and producer. In some reservoirs, interwell tracer data can be used to determine the influence of induced fracture features. The interwell tracers usually show very fast water movement.
Induced fractures in waterfloods and EOR projects can be caused by a number of mechanisms such as but not limited to, pressure depletion, changing pressure regimes, thermal effects, or plugging effects. These fractures can either be beneficial to the reservoir performance or effect performance negatively. Benefits include improved injectivity and increased throughput of the displacing fluid. Negative effects can come in the form of reduced volumetric sweep efficiency, impaired ultimate recovery or injected fluid losses out of zone.
Case studies, theory, and available literature from Western Canada will be reviewed in order to suggest and improve reservoir management strategies for waterfloods. We have completed hundreds of waterflood feasibility, waterflood management and EOR flood studies worldwide and continue to be amazed and humbled by the complexity that many waterfloods and EOR floods exhibit due to induced fracturing. WIF and EOR induced fractures (EIF) are common and should be analysed to optimize production. Growth of the WIF, response to waterflood with the presence of WIF, implication of WIF and reservoir management are the main areas which will be addressed.
Is Polymer Retention Different Under Anaerobic vs. Aerobic Conditions?
Authors: Wan Hao , Seright R. S. 
Published: March 2016

Abstract
This paper examines whether retention of partially hydrolyzed polyacrylamide (HPAM) is different under anaerobic versus aerobic conditions. Both static (mixing with loose sand) and dynamic methods (core floods) were used to determine HPAM retention. There are both advantages and disadvantages associated with determining polymer retention using static tests versus dynamic tests and using aerobic versus anaerobic conditions. From static retention measurements, polymer adsorption values on pure silica sand or Berea sandstone were small, and they showed little difference between experiments conducted aerobically or anaerobically. For both aerobic and anaerobic conditions, HPAM retention increased significantly with increased pyrite or siderite content. Static retention under anaerobic conditions ranged from 45-75 µg/g with 1% of either pyrite or siderite to 137-174 µg/g for 10% pyrite or siderite to 1161-1249 µg/g for 100% pyrite or siderite.
If iron minerals are present, the most representative polymer retention results are obtained (for both static and dynamic tests) if conditions are anaerobic. Retention values (from static measurements) under aerobic conditions were commonly twice those determined under anaerobic conditions. If iron minerals are present and retention tests are performed under aerobic conditions, TOC or some similar method should be used for polymer detection. Viscosity detection of polymer may provide retention values that are too high (because oxidative degradation can be misinterpreted as polymer retention). For a broad range of siderite content, retention from static tests did not depend on whether dissolved oxygen was present. However, for a broad range of pyrite content, HPAM retention was significantly lower in the absence of dissolved oxygen than under aerobic conditions. Theses results may be tied to iron solubility. When polymer solutions were mixed with 100% pyrite over the course of 12 hours, 360–480-ppm iron dissolved into polymer solutions under both aerobic and anaerobic conditions, whereas with 100% siderite, only 0–0.6-ppm iron dissolved. If dynamic methods (i.e., corefloods) are used to determine polymer retention under aerobic conditions, flow rates should be representative of the field application. Rates that are too high lead to underestimation of polymer retention. With 10% pyrite, dynamic retention was 211 μg/g at 6 ft/d versus 43.2 μg/g at 30 ft/d. In contrast, retention values were fairly consistent (40.6 – 47.8 μg/g) between 6 ft/d and 33 ft/d under anaerobic conditions.
Optimizing Water Chemistry to Improve Oil Recovery from the Middle Bakken Formation
Authors: Wang D. , Dawson M. , Butler R. , Li H. , Zhang J. , Olatunji K. 
Published: March 2016

Abstract
With the recent dramatic drop in oil price, production from ultra-tight resources, like the Bakken formation, may drop substantially. Since expenditures for drilling, completion, and fracking have already been made, existing wells will continue to flow, but oil rates will decline—rapidly in many cases. In a low oil-price environment, what can be done to sustain oil production from these tight formations?
We are testing a surfactant imbibition process to recovery oil from shales. We measured surfactant imbibition rates and oil recovery values in laboratory cores from the Bakken shale. After optimizing surfactant formulations at reservoir conditions, we observed oil recovery values up to 10–20% OOIP incremental over brine imbibition. However, whether or not surfactant imbibition will be a viable recovery process depends on achieving sufficiently high oil production rates in a field setting—which requires that we identify conditions that will maximize imbibition rate, as well as total oil recovery. In this paper, we describe laboratory evaluations of oil recovery using different core plugs. These recovery studies involved
(1) surfactant formulation optimization on concentration, salinity and pH, (2) characterization of phase behavior, (3) spontaneous imbibition, and (4) forced imbibition (flooding) with gravity drainage assistance.
In preserved cores, we observed: (1) Formulations using 0.1% surfactant concentration at 4% TDS salinity showed favorable oil recoveries (up to 40% OOIP). (2) Generally, surfactant formulations at optimal concentration and salinity were stable at high temperature (115°C). (3) Injectivity/permeability enhancements up to 75 percent occurred after acidification using acetic acid or HCl. (4) Wettability alteration is the dominant mechanism for surfactant imbibition. Of course, actions that increase fracture width will aid gravity drainage and oil recovery. This information is being used to design and implement a field application of the surfactant imbibition process in an ultra-tight resource.
Forecasting Incremental Oil Production of a Polymer Pilot Extension in the Matzen Field Including Quantitative Uncertainty Assessment
Authors: Chiotoroiu Maria-Magdalena , Peisker Joerg , Clemens Torsten , Thiele Marco R. 
Published: March 2016

Abstract
The polymer pilot project performed in the 8 TH reservoir of the Matzen field showed encouraging incremental oil production. To further improve the understanding of recovery effects resulting from polymer injection, an extension of the pilot is planned by adding a second polymer injector.
Forecasting of the incremental oil production needs to take the uncertainty of the geological models and dynamic parameters into account. We propose a workflow which comprises a geological sensitivity and clustering step followed by a dynamic calibration step for decreasing the objective function to improve the reliability of a probabilistic forecast of the incremental oil recovery.
For the geological sensitivity, hundreds of geological realizations were generated taking the uncertainty in the correlation of the sand and shale layers, logs, cores and geological facies into account. The simulated tracer response was used as dissimilarity distance to classify the geological realizations. Clustering was then applied to select 70 representative realizations (centroids) from a total of 800 to use in the full-physics dynamic simulation.
In the dynamic simulation, an objective function comprising liquid rate and tracer concentration of the back-produced fluids was introduced.
To further improve the calibration, the P50 value of incremental oil production as derived from simulation was compared with the incremental oil production determined from Decline Curve Analysis from the wells surrounding the polymer injection well. The mismatch between the P50 and the Decline Curve Analysis was improved by adjusting polymer viscosity.
The calibrated models were then used to for a probabilistic forecast of incremental oil due to an additional polymer injector and to estimate the expected polymer concentration at the producing wells.
Experimental Evaluation of Shale Oil Recovery from Eagle Ford Core Samples by Nitrogen Gas Flooding
Authors: Yu Yang , Sheng James J. 
Published: March 2016

Abstract
Production from tight formation resources leads the growth in U.S. crude oil production. Compared with chemical flooding and water flooding, gas injection is a promising EOR approach in shale reservoirs. A limited number of experimental studies concerning gas flooding in the literature focus on unconventional plays. This study is a laboratory investigation of gas flooding to recover light crude oil from nano-permeable shale reservoirs.
In this work, the N2 flooding process was applied to Eagle Ford core plugs saturated with dead oil. To investigate the effects of flooding time and injection pressure on the recovery factor, two groups of core-flood tests were performed. In group one, flooding time ranged from 1 to 5 days in increments of 1 day; in the other group, the injection pressure ranged from 1,000 psi to 5,000 psi in increments of 1,000 psi. The experimental setup was monitored using X-ray CT that helped to visualize phase flow and estimate the recovery efficiency during the test.
The potential of N2 flooding for improving oil recovery from shale core plugs was examined, and the recovery factor (RF) of each case was presented. The results from group one showed that more oil was produced with a longer flooding time. However, the incremental RF decreased with the increase of flooding time. The oil recovery was significant at the initial period of the recovery process, and a longer flooding time had less effect on extracting more oil. With flooding time constant in 1-day, the results from the second group indicated that RF increased with injection pressure, especially rising pressure, from 1,000 psi to 2,000 psi. The gas breakthrough time became shorter with the increase of injection pressure. The analysis of the CT number showed that the oil recovery process mainly occurred before the gas breakthrough. Once a fluid flow path was established, the injected gas flowed through the limited communication channels; thus, no extra oil could be extracted without increasing the injection pressure. This experimental study illustrates that gas flooding has liquid oil production potential in shale reservoirs.