bluuebunny/crossref_metadata_2025_split huggingface dataset:
Late bone metastasis from an apparently benign oncocytic follicular thyroid tumor
Authors: Boronat Mauro , Cabrera Juan J , Perera Carmen , Isla Concepción , Nóvoa Francisco J 
Published: September 2013

Summary
A man underwent total thyroidectomy for goiter when he was 62 years old. The pathology report informed on a 5.5 cm oncocytic follicular adenoma and a 3.5 mm papillary microcarcinoma. Due to the papillary tumor, he was treated with ablative radioiodine therapy and suppressive doses of levothyroxine. After uneventful follow-up for 9 years, increased levels of serum thyroglobulin were detected. Further imaging studies including a whole body scan (WBS) after an empirical dose of 200 mCi 131I were negative. Two years later, a 99mTc SestaMIBI WBS and a 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography showed a well-delimited focal uptake in the right femur. A bone biopsy of the lesion demonstrated metastasis of follicular thyroid carcinoma. Retrospective histological reexamination of available material from the primary oncocytic thyroid tumor failed to reveal definitive traits of malignancy.

Learning points

Oncocytic follicular thyroid tumors are a relatively uncommon variant of follicular thyroid neoplasms mostly composed of distinctive large oxyphilic cells (Hürthle cells).

Criteria for the distinction between benign and malignant oncocytic neoplasms are not different from those used in the diagnosis of ordinary follicular tumors.

Some cases of apparently benign oncocytic neoplasms have been found to develop malignant behavior.

Search to rule out vascular and capsular invasion should be particularly exhaustive in histological assessment of oncocytic thyroid tumors.

Even so, long-term surveillance remains appropriate for patients with large apparently benign oncocytic tumors.
New Water Depth Record for Electric Line Operations, Retrieving Asphaltenes with Riserless Light Well Intervention
Authors: Ashcraft Steven , Karlsen Ole Eddie , Luviano Angel , Morrison Bevan 
Published: September 2013

Abstract
Capabilities in the industry have been expanded on a recent operation performed in the Gulf of Mexico, where a new electric line (e-line) water depth record was set in addition to demonstrating that asphaltenes can be removed on e-line with Riserless Light Well Intervention (RLWI).
The operator had planned to set a removable hold open sleeve with a subsurface-controlled PB valve across a failed surface controlled subsurface safety valve (SCSSV) on one of their subsea wells. The well had not been re-entered since production start-up, which meant that the downhole conditions were unknown. During the slickline gauge run, the toolstring hung up after only 581 ft in the well and could not be jarred any deeper. After a failed attempt to chemically remediate the blockage, the client decided to try e-line milling, consisting of an e-line tractor for conveyance and a cleaning tool fitted with a reverse circulating bit to mill through the obstruction and capture any debris. This toolstring was initially set down in the production tubing at 4,083 ft ELM and was picked-up to 4,000 ft ELM. At this depth the cleaning tool was engaged and was able to mill at 10 fph past the previous hang up depth (HUD) of the slickline gauge. We continued downhole another 1,217 ft where an obstruction was encountered at 5,778 ft ELM and the toolstring became stuck. The toolstring was worked free and brought to the surface where it was established that the bit was packed with solid debris and the bailer sections were full of dense, hard-packed asphaltenes. The operator concluded that this very dense material would continue all the way down the well and decided that it was would not be feasible to continue milling as there were almost certain, terminal sticking risks.
Based on the samples recovered, the operator was able to avoid unnecessary costs incurred from attempting to work further downhole under these conditions. They decided to suspend operations until they had fully analyzed the samples and could make an informed decision on how best to remove the asphaltenes. This paper will discuss job planning, operations, and lessons learned.
Experimental and Numerical Analysis of Gas Transport in Shale Including the Role of Sorption
Authors: Alnoaimi K. R. , Kovscek A. R. 
Published: September 2013

Abstract
This study adds to the knowledge base of carbon dioxide sequestration and methane recovery enhancement from gas shale. If gas shale is desired to be used as a storage medium for CO2, then knowledge of how to maintain gas permeability while enhancing storage via sorption is mandatory. In this work, physical and numerical pressure-transient, pulse-decay experiments are conducted on Eagle Ford shale cores. The experiments are conducted isothermally at various pore and confining pressures that maintain a constant net effective stress. The gases investigated are helium, methane, and carbon dioxide. Porosity and permeability measurements are conducted using various techniques including numerical simulation that incorporates detailed measurements of the in-situ, core-scale porosity distribution. The research simulator is fully implicit, finite volume, unconditionally stable, and incorporates gas sorption in ultra-small pore networks. Langmuir sorption parameters are determined after matching the upstream and downstream pressure profiles simultaneously. Experiments are also interpreted using available analytical models and compared to the high-resolution simulations matched to experimental observations. Results highlight the interplay of gas slip and sorption of pure gases at core-level. Results also quantify the role of CO2 sorption in various shale fabrics and thus promote the potential for sequestration. While the gas molecular kinematic diameter plays a role in dictating the pore accessibility, and thus governs slip flow, gas sorption is more influential in determining permeability. Gas transport in wide channels, however, undermines the influence of sorption on measured permeability. While He is a non-sorptive gas, CH4 sorption isotherms are described by a Langmuir model and CO2 isotherms are similar to an n-BET model. The experiments demonstrate that He and CH4 have a similar measured permeability while carbon dioxide has a lower permeability. These differences are attributed to the strong sorption of carbon dioxide.
Optimized Well Modeling of Liquid-Rich Shale Reservoirs
Authors: Juell Aleksander Oma , Whitson Curtis Hays 
Published: September 2013

Abstract
This paper presents an integrated modeling approach for history matching and economic optimization of wells producing from liquid-rich shale reservoirs (LRSR). History matching uses daily pressures and gas-oil-water production data to estimate average parameters in a 2D/3D finite-difference (FD) horizontal multi-fractured well model: rock permeability, fracture half-length, relative permeabilities, and in-situ fluid (solution gas-oil ratio). Economic-based well design uses the same FD model to maximize net present value (NPV) by finding optimal well completion parameters: number of fractures, and fracture size. Revenue optimization (short-term and long-term) is performed with the same FD well model by finding the drawdown that maximizes revenue. For undersaturated gas condensate LRSR wells, optimal drawdown is often equal to or somewhat below the reservoir dewpoint pressure. We study optimal drawdown control for new wells that are optimized from start of production, and for wells that are optimized only after some initial period of sub-optimal drawdown control. We also compare short-term versus long-term economic optimization strategies.
We provide examples that clearly show the potential for improved economic development of LRSR using optimized well design and drawdown control, for new and existing wells. Our study shows a significant economic upside to proper selection of completion design, and for undersaturated gas condensate wells, optimal drawdown has significant potential to increase daily revenues.
Streamline-Based Time Lapse Seismic Data Integration Incorporating Pressure and Saturation Effects
Authors: Watanabe Shingo , Han Jichao , Datta-Gupta Akhil , King Michael J. 
Published: September 2013

Abstract
We present an efficient history matching approach that simultaneously integrates 4-D repeat seismic surveys with well production data. This approach is particularly well-suited for the calibration of the reservoir properties of high-resolution geologic models because the seismic data is areally dense but sparse in time, while the production data is continuous in time but averaged over interwell spacing. The joint history matching is performed using streamline-based sensitivities derived from either finite-difference or streamline-based flow simulation. Previous approaches to seismic data integration have mostly incorporated saturation effects but the pressure effects have largely been ignored. We propose, for the first time, streamline-based analytic approaches to compute parameter sensitivities that relate the seismic data to reservoir properties while accounting for both pressure and saturation effects via appropriate rock physics models. The inverted seismic data (e.g., changes in acoustic impedance or fluid saturations), is distributed as a 3-D high-resolution grid cell property or as a vertically integrated two-dimensional map. We derive pressure drop sensitivities along streamlines in addition to our previous work of water saturation sensitivity computation. The novelty of the method lies in the analytic sensitivity computations which make it computationally efficient for high resolution geologic models. We demonstrate the versatility of our approach by implementing it in a finite difference simulator which incorporates detailed physical processes, while the streamline trajectories provide for rapid evaluation of the sensitivities. The efficacy of our proposed approach is demonstrated with both synthetic and field applications. The synthetic example is the SPE benchmark Brugge field case. The field example involves waterflooding of a North Sea reservoir with multiple seismic surveys. For both the synthetic and the field cases, the advantages of incorporating the time-lapse variations are clearly demonstrated through improved estimation of the permeability distribution, pressure profile, and fluid saturation evolution and swept volumes.
Potential of Improved Waterflooding in Acid-Hydraulically-Fractured Shale Formations
Authors: Morsy Samiha , Sheng J. J , Gomaa Ahmed , Soliman M. Y 
Published: September 2013

Abstract
Water flooding is the economical secondary recovery method that has been used for more than seventy years in conventional oil reservoirs. However, few studies focused on water flooding viability in unconventional shale formations. The objective of this study is to improve the performance of waterflooding in shale formations by enhancing spontaneous imbibition through optimizing hydraulic fracturing fluid and fracture orientation. Core samples of Eagle Ford, Mancos, Barnett, and Marcellus shales were used in this study. Fractures were generated by cutting the core samples into two halves; some are along bedding planes and others across bedding planes. Shales usually have natural micro-fractures, (e.g. Eagle Ford Shale) and acid may enhance micro-fracture conductivity, so we want to investigate the impact of using low concentrations of HCl in the hydraulic fracturing process on spontaneous imbibition. Some of the samples were immersed in different HCl solutions to create etched fractures. We measured the porosity and the oil recovery in both the acid-treated and non-treated samples during spontaneous water imbibition for the samples with different fracture orientation. The mechanical properties of the acid-treated and non-treated samples were measured using different acid concentrations (1-3 wt%) at 200°F. The samples were 2.54 and 3.81 cm in diameter and 2.54 to 5.08 cm in length. The measured porosities were 1-3% for the non-treated samples and 1.3-10.5% for the treated samples. We observed that the oil recovery factors of the spontaneous imbibition for the samples treated with acid were 47% from Eagle Ford, 53% from Mancos, 28% from Barnett, and 38% from Marcellus. The recovery factors from the non-treated samples were 12% from Eagle Ford, 4% from Mancos, 13% from Barnett, and 3% from Marcellus. Furthermore, we observed that fracture orientation affects spontaneous imbibition in all of the studied rock formations, especially for Marcellus shale formation where the recovery factors varied from 4% for the samples cut across bedding planes to 38% for the samples cut along bedding planes. Eagle Ford samples showed the greatest reduction in Young's Modulus ranging from 25-82% when exposed to 1-3 wt% HCl solutions and 75% when exposed only to 5 wt% NaCl saline solution at 200°F. Our results showed that imbibition in unconventional shale oil formations could be improved by using low pH fracturing fluids and optimization of fracturing orientation.
Estimating Reservoir Composition for Gas Condensates and Volatile Oils from Field Data
Authors: Spivey John P. , McCain W. D. 
Published: September 2013

Abstract
This work describes a method for estimating reservoir fluid composition for gas condensates and volatile oils from readily available field data. Required data are separator conditions; first stage separator gas specific gravity, non-hydrocarbon impurities content, and gas-liquid ratio; and stock tank API gravity. The well must be stabilized, and the flowing bottomhole pressure must be above the saturation pressure.
A database comprising compositions for 23 wet gases, 33 gas condensates, and 19 volatile oils was taken from the literature. The data sets included compositions in mole fractions of methane through heptanes-plus and nonhydrocarbon impurities, along with molecular weight and specific gravity of the heptanes-plus fraction. The database was restricted to fluids with heptanes-plus content between 1 and 25 mole %, and with relatively low non-hydrocarbon impurities content (less than 4 mole % H2S, less than 6 mole % CO2, less than 11 mole % N2, and less than 18 mole % total nonhydrocarbons).
The method predicts reservoir fluid composition through heptanes-plus along with molecular weight and specific gravity of the heptanes-plus fraction. The resulting reservoir fluid composition may be used with an untuned equation of state to obtain preliminary estimates of saturation pressure, maximum liquid dropout, and modified-black-oil (MBO) fluid property tables for simulation. The predicted composition may also be used as a cross check of laboratory-measured composition.
The method has been tested on data sets for 16 gas condensates that were not part of the composition database. Predicted compositions were surprisingly accurate, with average absolute errors (AAE) for methane, 1.0 mole %; ethane, 1.2 mole %; propane, 0.7 mole %; butanes, 0.5 mole %; pentanes, 0.3 mole %; hexanes, 0.3 mole %, and heptanes-plus, 0.4 mole %. Predicted specific gravities and molecular weights of the heptanes-plus fraction had average absolute relative errors (AARE) of 1.3% and 9.7%, respectively. Saturation pressures calculated from the predicted gas-condensate compositions using an untuned equation of state had an average relative error (ARE) of −0.3% and an AARE of 6.9%, with a median relative error of -3.7% and a median absolute relative error of 4.5%.
Because of the current commercial importance of liquids-rich gas plays, the method should find application for 1) obtaining preliminary estimates of composition before laboratory data are available, 2) estimating PVT properties such as saturation pressure, maximum liquid dropout, and MBO fluid property tables from field data when PVT measurements are not available, and 3) cross-checking laboratory-measured compositions.
Effect of Wall Wettability on the Onset of Churning in Upward Gas-Liquid Annular Flow
Authors: Belfroid S. P. , Khosla V. , Nennie E. D , Alberts G. J. , Veeken C. A. 
Published: September 2013

Abstract
The influence of hydrophobic and hydrophilic tube walls on the pressure drop and liquid loading behavior was investigated in previous projects in the past. In this paper, results of visualization experiments and of experiments at different liquid-to-gas ratios and inclination angles are presented for hydrophobic tube walls. Experiments were performed in coated and uncoated steel and Perspex pipes of different diameters: 20 mm and 50 mm. Experiments with different deviation angles ranging from 0° (vertical) to close to horizontal (≈80°) were performed for the 20mm diameter tube. The impact of the wall wettability on the flow patterns was examined by performing flow visualizations with a high speed camera in coated and uncoated Perspex tubes. From the experiments it becomes clear that the hydrophobic coating prevents the formation of a liquid film on the tube wall. As a result, the transport of the liquid phase is solely in the form of droplets/ligaments. In the hydrophobic coated tube, the onset of churning is at a lower gas velocity than in the uncoated tube. The presence of the coating reduces the critical gas rate corresponding to the minimum pressure drop by as much as 40%. This decrease reduces for high liquid rates and for larger inclination angles. However, for a liquid content of LGR = 1000 Sm3/106 Sm3, the benefit is still 33% at a vertical flow and a reduction in the critical rate remains up to a deviation angle of 80°. The hydrophobic coating increases the friction at higher gas rate but reduces the hydrostatic head at lower gas rate with a 70% reduction at low liquid content.
Time-Delayed Fracturing: A New Strategy in Multi-Stage, Multi-Well Pad Fracturing
Authors: Manchanda Ripudaman , Sharma Mukul M. 
Published: September 2013

Abstract
The creation of a hydraulic fracture changes the stress distribution in the vicinity of the fracture. This stress shadow can influence the growth of subsequent fractures. Immediately after a hydraulic fracture treatment is pumped, the width of the propped fracture and the associated induced unpropped (IU) fracture network is at its maximum. The hydraulic fracture and the induced unpropped fractures close as a result of fluid leak-off over time. This implies that the stress shadow in their vicinity also decreases over time. Complete closure of induced, unpropped fractures can significantly reduce the stress shadow and make subsequent fracture stages less susceptible to fracture interference and more efficient by avoiding wastage of fluid / proppant into preexisiting fractures. This suggests that increasing the time between successive fractures in a wellbore will lead to improved fracture performance.
Using geomechanical computations we show that waiting for longer times between successive stages of a horizontal well allows for a reduction in the stress shadow and less fracture interference leading to a more efficient fracture network by successive fractures in a horizontal well. We, therefore, propose the idea of establishing a minimum time between successive fracture stages in a well. The time required for the induced un-propped fractures to close can be calculated from our models and varies based on the reservoir and fluid properties but is of the order of hours.
This controlled time-delay in fracturing can be achieved in several ways, without wasting valuable rig time in the field. We suggest several alternate innovative strategies to achieve this on the field. For example, two-well or multi-well zipper fracs can be pumped, hence increasing the time between fractures in a given well substantially (by several hours). Alternatively, in the Texas Two Step method it would be better to pump the fractures in the sequence 1, 3, 5, 2, 4 than the sequence 1, 3, 2, 5, 4 where the numbers represent the sequence of the fractures along a well starting at the toe. We propose several other fracturing sequences for multi-well pad fracturing applications and suggest how the impact of a multi-stage, multi-well pad fracturing treatment can be enhanced while conserving the time and resources used.
Psychological Care, Patient Education, Orthotics, Ergonomics and Prevention Strategies for Neck Pain: An Systematic Overview Update as Part of the ICON§ Project
Authors: Gross Anita R. , Kaplan Faith , Huang Stacey , Khan Mahweesh , Santaguida P. Lina , Carlesso Lisa C. , MacDermid Joy C. , Walton David M. , Kenardy Justin , Söderlund Anne , Verhagen Arianne , Hartvigsen Jan 
Published: September 2013

Objectives:To conduct an overview on psychological interventions, orthoses, patient education, ergonomics, and 1⁰/2⁰ neck pain prevention for adults with acute-chronic neck pain.Search Strategy:Computerized databases and grey literature were searched (2006-2012).Selection Criteria:Systematic reviews of randomized controlled trials (RCTs) on pain, function/disability, global perceived effect, quality-of-life and patient satisfaction were retrieved.Data Collection &amp; Analysis:Two independent authors selected articles, assessed risk of bias using AMSTAR tool and extracted data. The GRADE tool was used to evaluate the body of evidence and an external panel to provide critical review.Main Results:We retrieved 30 reviews (5-9 AMSTAR score) reporting on 75 RCTs with the following moderate GRADE evidence. For acute whiplash associated disorder (WAD), an education video in emergency rooms (1RCT, 405participants] favoured pain reduction at long-term follow-up thus helping 1 in 23 people [Standard Mean Difference: -0.44(95%CI: -0.66 to -0.23)). Use of a soft collar (2RCTs, 1278participants) was not beneficial in the long-term. For chronic neck pain, a mind-body intervention (2RCTs, 1 meta-analysis, 191participants) improved short-term pain/function in 1 of 4 or 6 participants. In workers, 2-minutes of daily scapula-thoracic endurance training (1RCT, 127participants) over 10 weeks was beneficial in 1 of 4 participants. A number of psychosocial interventions, workplace interventions, collar use and self-management educational strategies were not beneficial.Reviewers' Conclusions:Moderate evidence exists for quantifying beneficial and non-beneficial effects of a limited number of interventions for acute WAD and chronic neck pain. Larger trials with more rigorous controls need to target promising interventions
Do Stock Prices Influence Analysts' Earnings Forecasts?
Authors: Miller Jeffrey S. , Sedor Lisa M. 
Published: September 2013

ABSTRACT
This study uses an experiment with professional financial analysts to examine whether stock prices influence analysts' earnings forecasts. The findings indicate that analysts' revised forecasts made in response to a management earnings forecast differ depending on the level of uncertainty communicated by management's guidance and the stock price reaction to it. Lower (higher) stock price leads to lower (higher) analysts' forecasts when uncertainty about future earnings is high, but not when uncertainty about future earnings is low. Overall, the evidence suggests that the documented association between prior security returns and analysts' earnings forecasts is due, at least in part, to the influence of stock price on analysts' earnings forecasts.
Data Availability: Contact the authors.