bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acquired haemophilia A in an elderly patient related to relapsed cervix carcinoma
Authors: Atilla Fatos Dilan , Unat Ahmet Alp , Bulbul Hale , Ulukus Murat , Demirci Zuhal , Saydam Guray , Sahin Fahri 
Published: May 2019

Abstract
Acquired haemophilia A (AHA) is a rare, autoimmune disease, presenting as sudden haemorrhages without any personal or family history. Anti-factor VIII (FVIII) is the most commonly recognised autoantibody resulting in decreased factor activity. The aetiology and pathophysiology of these antibodies remains unclear. Approximately 50% of reported cases are idiopathic; the rest are associated with other conditions, mainly underlying malignancies, autoimmune diseases (eg rheumatoid arthritis (RA), systemic lupus erythematosus), drug administration and postpartum period. A 74-year-old woman presented to our institution with haematochezia and haematuria. She had a medical history of cervix carcinoma; total abdominal hysterectomy and bilateral salpingo-oophorectomy with postoperative chemoradiotherapy was performed in 2011. She had also been followed up for 20 years for deforming and severe RA, which was in low-disease activity with methotrexate and corticosteroid. Laboratory investigations for abnormal bleeding revealed prolongation of activated partial thromboplastin time (APTT). APTT prolongation was not corrected by 50:50 plasma mixing studies, and a confirmatory factor assay demonstrated FVIII deficiency (1.4 IU/dL; normal range 50-150 IU/dL). Positive FVIII antibodies on Bethesda testing confirmed a diagnosis of AHA. A rectosigmoid mass and fistula between rectum and bladder were discovered by computed tomography (CT). Bleeding was controlled with recombinant activated factor VII (rFVIIa) after two weeks. Eradication of the inhibitor was achieved with high-dose pulse methylprednisolone for two days and then 2mg/kg daily over four weeks.
TURKEY’S REFUGEE POLICY UNDER THE SHADOW OF THE NEO-OTTOMANISM: A SOURCE OF SILENT CONFLICT?
Authors: Kaya Osmanbaşoğlu Gülsen 
Published: May 2019

Along with Turkey’s changing refugee policy from the Eurocentric, secular nation-state ideology to the neo-Ottomanist one on the state level, there also exist main handicaps on the micro power level concerning the successful coordination of the refugee issue with full respect of the human rights. Economic, cultural and especially political factors play a role in the relationship between Syrians and Turkish residents. Fragmentation within the Syrian community living in Turkey is also evident. On the other hand, different from the state policy, Turkish people implicitly show their reluctance towards this migration wave without creating a social turmoil. In this line, it is suggested here that Neo-Ottomanism, as a rising trend, helps a considerable majority of the society to take a moderate stance towards the immigration flux.
Interpretação e validação de agrupamentos em análise de cocitação de autores: estudo exploratório e metodológico
Authors: Carvalho Rodrigo Aquino de , Carvalho Catarina de Quevedo Prestes de , Caregnato Sônia Elisa 
Published: May 2019

No contexto da fase de interpretação e validação de uma Análise de cocitação de Autores, são formulados os seguintes objetivos: (i) comparar dados dos artigos citantes do corpus com dados que caracterizam os citantes e os autores citados de um agrupamento de uma ACA; (ii) propor indicadores adicionais relacionados aos autores que formam um agrupamento; e (iii) visualizar a rede de documentos cocitados dos autores que formam o agrupamento. O trabalho é exploratório e metodológico e os dados foram retirados de 151 artigos da área da Organização do conhecimento, do período de 2011 a 2015, recuperados na Web Of Science. Uma matriz simétrica com 50 posições (autores com nove ou mais artigos citantes) gerou cinco agrupamentos. O principal agrupamento (17 autores) é o objeto dessa análise. Os autores são cocitados em 69 artigos. Das 131 relações dos autores nas referências, 84 ocorrem no parágrafo. Há dados que comparam citações, citantes e documentos citados para cada um dos 17 autores. São citados 230 artigos distintos no agrupamento. Conclui-se que a proximidade da cocitação no parágrafo valida o agrupamento e que os demais dados ampliam a visão da formação e da caracterização das relações de cocitação. Os resultados demonstram que os agrupamentos em uma ACA podem ser analisados como unidades autônomas e que a descrição dos dados que sustentam a formação do agrupamento (artigos e autores citantes) e que caracterizam os autores participantes e a rede de documentos cocitados, colabora na validação e interpretação das relações, pois apresenta dados objetivos. Espera-se que essa abordagem exploratória possa ser aplicada em outras ACA, independente da área.
PROTON DRIPLINE FOR ISOTONE N = 18, 20, AND 22 USING MODIFIED RELATIVISTIC MEAN FIELD (MRMF) MODEL
Authors: Diningrum Jenny Primanita , Sulaksono Anto 
Published: May 2019

Determining the position of one- and two-proton dripline for isotone of N = 18, 20, and 22 has been studied through Modified Relativistic Mean Field (MRMF). The model exemplifies three impacts, namely isovector-isoscalar coupling, tensors, and electromagnetic exchange through five parameter set variations. The position of one- and two-proton dripline for the isotones is predicted by applying two methods, which are two-proton separation energy, and Fermi energy. The research shows that the prediction of one- and two-proton dripline for isotone of N = 18, and N = 20 is positioned at Z = 22 and Z = 26 consecutively. Then, the prediction of one- and two-proton dripline for isotone of N = 22 has two positions, Z = 26 and Z = 28. The calculation result indicates that the position prediction for isotone of N = 18, N = 20, and N = 22 is following the research result conducted by Nazarewicz with RMF+NLSH model [1]. Meanwhile, isovector-isoscalar coupling, tensors, and electromagnetic exchange do not affect massively for the position prediction of two-proton dripline. However, the three methods affect one-proton dripline.
Sparse Representation of 4D Seismic Signal Based on Dictionary Learning
Authors: Soares Ricardo Vasconcellos , Luo Xiaodong , Evensen Geir 
Published: May 2019

Abstract
This work presents the use of Dictionary Learning methods for a sparse representation of 4D seismic data in history matching. We consider a trade-off between the number of coefficients retained in the sparse data representation, the computational cost, and how well we can capture the main features of the 4D seismic signal. K-SVD is an iterative algorithm used in Dictionary Learning problems that alternates between the calculation of the sparse representation vector and dictionary update. For the definition of the sparse representation vector, one can constrain the problem into two distinct approaches: (1) sparsity-constrained; and (2) error-constrained. We evaluated the two methods and the influence of critical parameters of the algorithm (dictionary size, number of iterations, patch size, and training dataset size) using a synthetic reservoir model. Results showed that regardless of which of the constrained approaches we used, the dictionary learning method can capture the main features of the 4D seismic signal with a sparse representation. However, the number of nonzero coefficients is highly dependent on the approach. Besides, dictionary size, number of iterations, patch size, and training dataset size, also have a significant impact on the number of coefficients and the computational cost. Consequently, the selection of these variables is crucial as it might affect the history-matching process. In a permanent-reservoir-monitoring (big data) scenario, the use of sparse representation allows us to retain the main features of the reservoir in a reasonably sized data representation that can be directly used in a history matching method, leading to improved reservoir characterization and a better understanding of the reservoir properties. This paper gives a practical implementation of a technique already used in other areas (image denoising, processing of raw seismic data, and facies representation) applied to 4D seismic data.
Adsorption of Crude Oil Polar Components onto Silica-Rich Chalk and its Impact on Wetting
Authors: Klewiah Isaac , Piñerez Torrijos Iván Darío , Strand Skule , Puntervold Tina , Konstantinopoulos Miltiadis 
Published: May 2019

Abstract
Adsorption of polar crude oil components exert a major impact on chalk wetting, and adsorption effects have been reported on water-wet pure Stevns Klint outcrop chalk (&gt;99% CaCO3). Aalborg chalk is a silica-rich material also used as analogue rock material for chalk reservoir studies. This work aims to characterize the impact silica minerals will have on polar crude oil component adsorption, and core wettability.
Silica-rich (6-8 At %) Aalborg chalk cores with initial water saturation (Swi) of 10% were flooded with a crude oil with acid and base numbers (AN and BN) equal to 0.35 mg KOH/g of oil. Effluent crude oil samples were analyzed, detecting changes in the AN and BN concentrations at the core outlet. Wettability was determined by spontaneous imbibition (SI), and further confirmed by chromatographic wettability tests.
Adsorption of polar crude oil components was observed to be an instantaneous process. The adsorption of polar acidic components onto the Aalborg chalk surfaces was less profound as previously observed in Stevns Klint chalk. However, adsorption of polar basic components was significantly higher in Aalborg chalk, which could be explained by the presence of negatively charged silicate surfaces. The water wetness of the Aalborg Chalk core was significantly reduced after the crude oil exposure.
This comparative study on both Aalborg and Stevns Klint chalk highlights the impact of silica content on adsorption of polar components and initial wetting. The findings contribute with essential information for the development of theoretical and chemical models to describe initial reservoir wetting and explain oil production profiles in chalk reservoirs during normal water injections, or during wettability alteration with Smart Water.
Understanding Loss Mechanisms – The Key to Successful Drilling in Depleted Reservoirs?
Authors: Scheldt Therese , Andrews Jamie Stuart , Lavrov Alexandre 
Published: May 2019

Abstract
An important measure for increasing oil and gas recovery is infill drilling. For mature fields, drilling and completion of new wells can be challenging due to a limited (or non-existent) operational window. The operational window is defined by an upper and a lower bound. The lower bound is usually based either on the pore pressure or the borehole stability limit, whichever is higher. The upper bound is an estimate of the maximum hydraulic pressure the wellbore wall can be exposed to without experiencing fluid loss (called Fracture Gradient, FG). Losses can occur in all types of reservoirs, but depleted reservoirs are more prone to losses because of reduced pore pressure and the decreasing in-situ stress. With reducing stress, the fracture propagation pressure decreases, and it becomes easier to open and drive a hydraulic fracture. A mitigating factor is to reduce mud weight, but this is not always possible in cases of differential depletion where there can be a complex distribution of pore pressure and fracturing pressure along the well. In many such cases, a FG much larger than the fracture propagation pressures in the low-pressure zones is required so that a mud weight can be selected that will balance the high-pressure zones. Such strategies then rely on the extra "strength" provided by the wellbore and specialized particles. Lost-circulation issues lead to non-productive rig time and direct costs associated with lost volumes of mud. If not managed correctly, they may also lead to loss of well/technical sidetrack and, in the worst case, serious well control incidents. Understanding the mechanisms in play is crucial for curing losses, since lost circulation materials used to treat losses caused by induced fractures are not necessarily effective against losses in naturally fractured rocks because of differences in fracture aperture and connectivity. Numerical modelling and analysis of lost-circulation mechanisms are presented in this article. Losses at so-called weak points are addressed and analysis of field data is discussed. Different potential influences on the FG are considered. Effects of varying rock properties and reservoir depletion, and different borehole geometries are modelled and discussed. Shale/sand interfaces are modelled as potential weak-zones and the resulting shear stresses across such interfaces are analyzed during drill-out. We find that such interfaces can be potential weak-zones and that boreholes with non-circular shape are more likely to experience tensile fracturing and mud losses. This highlights the challenges when estimating FG for heavily depleted reservoirs and it confirms the understanding that poor drilling practice which can create weak-points can directly reduce the FG (in addition to unfavorable ECD conditions in well).
World First Simultaneous Jetting of 72 Laterals with Solids Control - Technology Development and Field Trial
Authors: Bjørnseth Fabian , Kristiansen Tron Golder , Flatebø Roar , Reinertsen Trond , Caline Yann , Østensen Ragnhild , Tomczak Daniel , Solhaug Kristian , Leinenbach Maximilian , Jørgensen Thomas 
Published: May 2019

Abstract
This paper presents the development and installation of a modified stimulation system, based on an existing system, field-proven for more competent formations. The system simultaneously deploys 0.8 cm diameter, 12 m long needles from the main bore by jetting into the formation. Modifications have been made to facilitate production from a soft chalk formation, which is prone to plastic deformation and liquefaction under the stresses of production. The original design of single titanium needles has been changed to a combination of an aluminum outer needle for the deployment phase, and a titanium slotted inner needle for the production phase. The aluminum needle is dissolved by pumping hydrochloric acid, enabling production through the inner needle.
The objective of the system is to reduce cost by simplifying the stimulation to a single pumping job, while achieving production enhancement for wells drilled in pay zones of less than 25-meter thickness. The objective of the field trial was to confirm the system could be deployed offshore, and to evaluate its production performance.
A series of functional tests to ensure pressure integrity of the modified design were performed in the lab. Promising lab test results were extended to functional yard trials, to verify the chance of success at downhole-like conditions. The running procedure was modified to honor well control requirements, while optimizing the likelihood of successful deployment of the system.
The paper presents the results of the qualification testing. The experiences from the installation and jetting are discussed in detail. Interpreted pumping pressure charts are presented for discussion. The productivity results are presented and compared to conventionally stimulated Valhall producer wells.
The installation of the jetted needles system with solids-control slotted laterals is the first of its kind in the world. The results of lab and yard testing presents a solution for achieving solids control in laterals jetted out from the main bore. Analysis of the deployment data provides grounds for future optimization of the system. The productivity results are used to evaluate whether the system is ready for full scale deployment across an entire horizontal well.
Practical Method to Benefit from the Improved Accuracy of Combining Overlapping Wellbore Surveys
Authors: Bang Jon , Ali Tarig , Ledroz Adrián 
Published: May 2019

Abstract
Weighted averaging of overlapping surveys will improve the estimate of the wellbore position and reduce the position uncertainty. An existing, rigorous method describes how the optimal weight factors can be achieved. However, the rigorous method is not commonly used, because of the complexity of the data management and processing.
We have developed a procedure for creating a combined instrument performance model (IPM) file that directly yields the reduced uncertainty of the averaged surveys, when it is applied as input to standard position error analysis. This represents an important step towards simplification of the rigorous procedure. Comprising inclination- and azimuth-dependent weight factors, one such file may be valid for any wellbore profile at any direction, and over an entire oil field. This is demonstrated in the paper for various synthetic well profiles, through comparison with results obtained by the rigorous averaging procedure.
The combined IPM file facilitates the simultaneous use of all available survey information in a consistent way. This may yield significant improvements to the wellbore position accuracy. Furthermore, the new procedure may help in the construction of instrument performance models for new survey tools that incorporate fixed combinations of sensor packages, which may result from recent years’ development of solid state sensors.
Disruptive Clamp-On Technology Tested for Mud Measurement
Authors: Olsvik Kenneth , Hansen Jondahl Morten , Toftevåg Kjell Rune , Kippersund Remi , Elseth Geir , Kjøsnes Ivar 
Published: May 2019

Abstract
During drilling operations, it is of vital importance to have accurate and reliable volume control, with as fast as possible detection of flow abnormalities. The earlier a flow abnormality is detected; the faster actions can be taken to minimize the consequence and cost of a potential well control incident. Accurate and reliable measurements of the inflow of mud and return flow is key to improvements in volume control and early kick detection. Uncertainty and time delay in these measurements may lead to well control incidents such as uncontrolled fracturing, collapse of wells, influx and, in worst case, external spill of oil and gas to the surface.
Existing inline traditional meters experience challenges due to clogging of measurement ports, mechanical erosion or damages on gaskets. Such being caused by the nature of mud consisting of a mixture of heavy materials and cuttings from the formation. Most of them are also not able to give quantified measurements, relying on human interpretation of trends in the data.
Using Clamp-on flow meters for mud measurement would significantly reduce cost, risk and maintenance work if it could generate accurate and reliable measurements. However, due to its nature, drilling mud is a difficult medium to measure and several other technologies have come short trying to do so, including previous ultrasonic measurement techniques.
This non-invasive ultrasound transmission concept, enables off-center beam transmission, forming the functionality of a multi-beam inline acoustic flow meter. The patented technology achieves this through disruptive acoustic guided wave transmission technology where the pipe wall is used as an advanced transmitting gateway between sensors, and helical shaped transducers enables measurements off-center signal transmission creating shorter paths than traditional clamp-on Meters in addition to traditional axial signal transmission. Combining these features enables measurements also through mud.
This paper will present the theory behind the technology, technology advantages and potential, as well as flow test results from mud flow loop at a Mud loop testing facility in Norway performed in September 2018 where the Meter was subjected to detecting incremental changes in flow rate of mud at different flow rates.
Digital Well Planning, Well Construction and Life Cycle Well Integrity: The Role of Digital Experience
Authors: Brechan Bjorn , Sangesland Sigbjorn 
Published: May 2019

Abstract
Automation is about to bring major changes to the work process for well planning. The next generation well planning tools will take the steps to higher levels of automation, which can provide step changes in quality of the planning, safety aspects in operations and reduce time and cost for planning and operations.
This article discusses the changes that will follow a new standard in well planning and operations. Analysis of the current practices and investigating the potential of a fully automated planning tool leads to a complete re-structuring of the work process. Well planning is a multidisciplinary activity where representatives from the different subsurface disciplines collaborates with the wells engineers in a compromise-prone process often with multiple iterations due to the differences in objective and understanding. The arrival of cross discipline 3D visualization tools has led to improvements in average duration of planning, but it is still a process depending on the efforts of the participating individuals and their level of experience. In an era where computers are landing passenger planes and the pilot has a verification role, it is time to look at the potential in digitalization for well planning and operations.
Many software developers are familiar with the difficulty in developing a "solution" to a challenge in a complex environment such as well construction and production. Many areas of expertise are involved and it is easy to end up with a compartmentalized product which is specialized for one area or a specific challenge. Establishing links and communication to all engineering and calculations in Wells, Subsurface and Production (e.g. well integrity data) are a matter of cost and safety. The next generation well planning tools has to incorporate all areas of expertise from planning well construction, through producing wells to final P&A.
The key enabler for automating the well planning process is the digital experience module, which will be the main task and focus for the Wells Teams. With built in experience, the application has rules and enhanced algorithms allowing Subsurface Teams to make accurate well plans and mature optimal well designs without involving the Wells Teams. Subsurface can identify the optimal drainage and well path including anti-collision, future side tracks, regulations in governing documentation and follow "local best practice". The Wells teams are ultimately responsible and will verify the well path generated by the software, and do any required updates.