bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ed-Drill MPD Dual Gradient Drilling for Challenging Pressure Regimes
Authors: Malt Roar , Stave Roger 
Published: June 2014

MPD - Managed Pressure Drilling technologies have been successfully implemented over the last decade. The technique is also frequently used on floating drilling units. MPD is primarily understood as a technique where back pressure is applied in combination with a low density mud weight and a Rotating Control Device (RCD) - effectively raising the bell nipple into the derrick of the drilling rig.
However, within the MPD segment there is a sub-group defined as Dual Gradient Drilling (DGD). These techniques are specific for floating drilling units and allow the use of a higher, overbalanced mud weight.
EC-Drill is a technique that falls within the DGD segment. In its current form it is not providing "full dual gradient", instead it is eliminating the effect of dynamic circulating pressure (ECD) and enabling drilling with a close to constant bottom hole pressure (BHP). This may still impact well design by allowing casing points to be extended. The technique is ideal low mud weight environments and depleted fields where lowering the mud weight to allow for application of back-pressure may be impossible. EC Drill is also a valuable tool in loss regimes and it may be used to ensure good cement jobs in deep water preserving the integrity of the well.
A subsea mud pump is connected to the riser annulus where it controls annulus pressure by manipulating the fluid level within the riser - effectively lowering the bell nipple under water. The change in bottom hole pressure is directly related to the change in fluid level - or suction pressure of the subsea pump. Contrary to MPD with back pressure, this additional system or equipment is not part of the primary well barrier.
The EC-Drill technology has been successfully deployed on jack-ups and on s SEMIS in deep water.
The Paper will present the technology and some case histories
Continuous Motion Rig (CMR Technology) - A Step Change In Drilling Efficiency
Authors: Skjaerseth Odd B. 
Published: June 2014

During the last 20 years the drilling industry has been through extensive mechanization and automation of tasks on the drill floor previously done manually. However the efficiency of operations has not improved through this development, neither has the development been able to improve well safety, an important aspect of drilling and well operations.
During the same period the costs of rig rental and services associated with drilling operations have had a significant increase. The increased cost for drilling is an essential aspect in the discussion of oil recovery from existing reservoirs and in the decision to explore new structures, thereby affecting the oil revenue of oil companies and governments. The importance of lowering drilling costs has been clearly pointed out at various industry conferences.
Mature oil provinces will experience an unnecessary decrease in oil production due to extensive drilling costs. The ability to reduce these costs is urgent and is heavily addressed by the major operators. Significant more drilling is necessary to prolong the production on the many mature fields As the drilling for oil and gas is moving into more demanding areas the need for safer drilling practices is imminent. The drilling industry has after several accidents a need for improved equipment that yields a higher standard in well safety.
West Drilling Products AS has invented and patented a new generation drilling technology - Continuous Motion Rig (CMR), a technology that promises a significant breakthrough in drilling efficiency, cost savings and well safety. CMR technology has a potential to reduce drilling time with 50 % and overall drilling costs with 40 – 50 %.
The main principle in this new breakthrough technology is to be able to run jointed drill pipe and casing continuously, to drill continuously while maintaining circulation. The CMR technology facilitates Underbalanced Drilling, MPD, and full snubbing capabilities. CMR will be the first fully robotize drilling process.
This paper will present the CMR technology, the development status and that the CMR Technology is a valuable and visible contribution of lowering drilling costs and introducing higher standard in well safety.
Safe and Efficient Tophole Drilling using Riserless Mud Recovery and Managed Pressure Cementing
Authors: Stave Roger , Nordas Philip , Fossli Borre , French Christopher 
Published: June 2014

Riserless dual gradient technology enables drilling tophole with weighted and engineered mud without discharge to sea. A Suction Module is run and installed subsea. This has a collection chamber where well returns are collected and diverted to a subsea mud pump. A Mud Return Line allows pumping or lifting the mud and cuttings back to surface.
In this way a "closed loop system" is established; mud and cuttings are collected at seafloor and returned to the shakers as with post-BOP drilling techniques. The technique eliminates discharges of mud and cuttings at seafloor and thereby a weighted and engineered mud system may be used to solve difficult drilling challenges, improve drilling efficiency and safety.
Selection of the technology is typically driven by its ability to impact drilling efficiency and safety, but in environmental sensitive areas also by the fact that discharges to sea can be reduced or totally eliminated. The technology also in many cases allows setting of the 20" casing deeper, eliminating an extra liner across problem zones.
A spin-off technology is Managed Pressure Cementing - MPC; Once the first surface casing is landed and circulation of cement starts, the subsea mud pump is used to control annulus pressure. The pressure is controlled during circulation of the cement slurry to avoid fracture and losses. Performance of the MPC system provides evidence of successful placement of the cement and that pressure develops as planned during the setting time.
RMR provides superior hole quality and MPC improves the quality of the cement job. In combination the structural integrity of the surface casings are improved.
The Paper will present the RMR and MPC technologies and some case histories.
Subsea Water Treatment and Injection for IOR and EOR
Authors: Hegdal T. , Pinchin D. 
Published: June 2014

The patented SWIT technology enables production and injection of clean sea water directly from the seabed, a flexible and cost effective solution. The technology, proven and ready to use, enables a step change in reservoir and asset management, accelerating production and increasing recovery. A new test proved that a combination of SWIT and membranes can produce low salinity and sulphate free water for a long time without any degradation in performance.
The SWIT technology offers a different approach to how reservoir and assets are managed and produced. Cleaning the surrounding sea water at the seabed and feeding directly into subsea injection wells is a completely different concept than the traditional topside approach. The benefits are significant from many aspects; reduced weight and area required topside; no long reach platform water injectors (WI) required; acceleration of production; increased recovery through flexible and phased deployment of the WI capacity required.
In 2009 – 2010, a 15 months full scale pilot test was carried out at the seabed in the Oslo fjord. The SWIT cleaned water was pumped to shore to NIVA Marine Research Centre for monitoring and testing. The results exceeded expectations and documented superior water quality for WI compared to traditional topside facilities. The Joint Industry Project (JIP) companies verified the results and technology is ready to be used in field applications. SWIT has been approved via technology qualification program with major oil companies.
The superior quality water from SWIT, including the ability to control the chlorine level very accurately, paves the way for producing low sulphate and low salinity water at seabed. A second test proved that SWIT feeding membranes make membranes last very long without any degradation in performance or maintenance requirement. SWIT combined with membranes therefore enables low sulphate and low salinity water injection from seabed. Currently planning is ongoing to design and build a full integrated sulphate free and low salinity water facility at the seabed.
Large Wire Rope Mooring Winch Drum Analysis And Design Criteria
Authors: Childers M.A 
Published: June 2014

ABSTRACT
Flange splitting is the most common cause in mooring winch failure. Conventionally designed winches have failed on a number of occasions when sizes of, about 3" to 3 1/2" diameter wire ropes in lengths up to 10,000 feet were employed for mooring large construction barges and semi-submersible offshore drilling units. It is believed that this is due to improper approximation of the field loading patterns on the winch, inadequate knowledge of actual forces transmitted onto the flange and drum barrel of the winch and/or defects in the structural joint between the flange and the drum barrel. The available design methods are often empirical, modified or extrapolated from work done using very small wire ropes and drums a decade ago. The application of these techniques to a multilayered winch using large diameter wire rope has proven to be unrealistic. The authors have therefore developed a method to calculate the flange thrust load and the barrel external pressure for winches using large diameter wire ropes. Also, a general guide for design and analysis of such winches and the effect of the lateral modulus of elasticity of wire rope on the reduction in the layer tensions is presented.

INTRODUCTION
Large wire rope winches are increasingly coming into use for off-shore construction, pipe laying and drilling vessels operating in deep water due to the advantages of mooring with wire or a combination of chain and wire as opposed to mooring with chain only. Winches using about 3" to 3 1/2" diameter wire ropes up to five to ten thousand feet in length and stacked up to 15 or more layers under high tensions have been in use. And even larger winches are being contemplated as the search for hydrocarbons and minerals from and under the oceans expands into deeper waters. An industry-wide survey revealed that several large winches used on lay barges and semi-submersible drilling units have failed in service exposing the owners to millions of dollars in repair or replacement costs on these winches, plus the damaging downtime and delay to the programs on which these units may have been engaged. An in-depth study into the probable causes of these failures revealed that the state of the art in design of large winches, in practice, remained more or less empirical and that in some instances, quality control in manufacture was not being taken as seriously as this equipment warrants. In addition, neither the wire rope nor the winch manufacturers have established wire rope characteristics which are necessary for designing winches. The wire rope characteristics which vary according to rope formation, type of core, rope diameter and material properties of components, the number of layers, the number of wraps on each layer and the operational tension on each layer affect the over-all structural loading on a winch. It is known that as the rope gets larger and stiffer, as the number of layers increase and as the wire winding tension is maintained high, the resulting forces on the barrel and the side flanges likewise increase.
Assembly of the Magnus Tower
Authors: Carmichael A.J. , Garga P.K. 
Published: June 2014

ABSTRACT
The heaviest one piece steel offshore structure in the world, for the B.P. Magnus Field in the North Sea, was completed in spring 1982. Important physical, structural and dimensional aspects, encountered during the assembly of the tower in the dry dock, are reviewed in this paper.

INTRODUCTION
The Magnus platform is a self-floating, X-braced, steel structure installed in British Petroleum's Magnus Field, which is located 200 km north east of the Shetlands Islands. The structure stands in a water depth of 186 metres, supports a topside load of 34,000 tonnes and is fixed to the seabed by 36 piles in clusters of 9 at each of the 4 legs.
The overall height of the structure is 210 ametres The base dimensions are 85 × 85 metres and the top deck dimensions are 56 × 62 metres. The large inherent buoyancy of this platform concept is provided by two 10.5 metre diameter legs extending the complete height of the structure and an 8 metre diameter by 70 metre long integral buoyancy tank located in the lower part of the platform. The structure has four outer frames, six levels of submerged plan bracings and two levels of above water plan bracings, which form the chords of the integral deck trusses.
The platform was built on its side in the dry dock facility of Highlands Fabricators at Nigg Bay, Scotland. Figs. 1 and 2' give an overall view of the tower in its construction orientation. The float-out weight of the complete tower was 40,400 tonnes.

BASIC PHILOSPOHY OF ERECTION SEQUENCE
The choice of erection sequence is the starting point for the fabricators overall project programme, which, in turn, forms the base for all pipemill, fabrication, painting and assembly programmes. It also highlights the requirements for subcontracting fabrication work.
Major considerations which lead to the adoption of a particular erection sequence are:Minimising the work which has to be carried out in-the-air. Welding at height is highly weather dependent, presents logistical problems in achieving good quality, requires special scaffolding arrangements and is labour intensive. For these reasons, it is time consuming and costly. This consideration generally results in a small number of very large assemblies, within the lifting capacities of available cranage. These assemblies should be as complete as possible with piping, equipment, anodes, paintwork, access ways and temporary scaffolding.Chosing erection items which have some inherent flexibility or are of simple structural form to enable fit-ups at the erection joints to be easily adjusted within the specification tolerances. If the item is excessively stiff or complex, or if the item requires a large number of fit-ups to be made to secure it into the structure, it can lead to poor fitups and high in-built stresses.Chosing erection items which are not difficult to assemble at ground level and move to the final erection location.
T Cell Activation Regulates CD6 Alternative Splicing by Transcription Dynamics and SRSF1
Authors: da Glória Vânia G. , Martins de Araújo Mafalda , Mafalda Santos Ana , Leal Rafaela , de Almeida Sérgio F. , Carmo Alexandre M. , Moreira Alexandra 
Published: June 2014

Abstract
The T cell-surface glycoprotein CD6 is a modulator of cellular responses and has been implicated in several autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, and psoriasis. During Ag presentation, CD6 is targeted to the immunological synapse in a ligand binding-dependent manner, in which CD6 domain 3 directly contacts CD166, expressed on the APC. T cell activation results in the induction of CD6Δd3, an alternatively spliced isoform that lacks the ligand-binding domain and thus no longer localizes at the immunological synapse. In this study, we investigated the molecular mechanisms regulating the expression of CD6Δd3 upon human primary T cell activation. Using chromatin immunoprecipitation, we observed an increase in RNA polymerase II occupancy along the CD6 gene and augmented CD6 transcription. We showed that activation leads to transcription-related chromatin modifications, revealed by higher CD6 acetylation levels. Modulation of chromatin conformation using a histone deacetylase inhibitor that increases transcription rate causes an increase of exon 5 skipping. We further showed that the splicing factor SRSF1 binds to a regulatory element in CD6 intron 4, activating exon 5 splicing and promoting exon 5 inclusion. Concomitant with T cell activation-induced exon 5 skipping, we observed a downregulation of SRSF1. Using RNA immunoprecipitation, we showed that in activated T cells, SRSF1 recruitment to the CD6 transcript is impaired by increased chromatin acetylation levels. We propose that upon T cell activation, SRSF1 becomes limiting, and its function in CD6 exon 5 splicing is countered by an increase in CD6 transcription, dependent on chromatin acetylation.
Infiltrating Monocyte-Derived Macrophages and Resident Kupffer Cells Display Different Ontogeny and Functions in Acute Liver Injury
Authors: Zigmond Ehud , Samia-Grinberg Shany , Pasmanik-Chor Metsada , Brazowski Eli , Shibolet Oren , Halpern Zamir , Varol Chen 
Published: June 2014

Abstract
The liver has a remarkable capacity to regenerate after injury; yet, the role of macrophages (MF) in this process remains controversial mainly due to difficulties in distinguishing between different MF subsets. In this study, we used a murine model of acute liver injury induced by overdose of N-acetyl-p-aminophenol (APAP) and defined three distinct MF subsets that populate the liver following injury. Accordingly, resident Kupffer cells (KC) were significantly reduced upon APAP challenge and started recovering by self-renewal at resolution phase without contribution of circulating Ly6Chi monocytes. The latter were recruited in a CCR2- and M-CSF–mediated pathway at the necroinflammatory phase and differentiated into ephemeral Ly6Clo MF subset at resolution phase. Moreover, their inducible ablation resulted in impaired recovery. Microarray-based molecular profiling uncovered high similarity between steady-state KC and those recovered at the resolution phase. In contrast, KC and monocyte-derived MF displayed distinct prorestorative genetic signature at the resolution phase. Finally, we show that infiltrating monocytes acquire a prorestorative polarization manifested by unique expression of proangiogenesis mediators and genes involved with inhibition of neutrophil activity and recruitment and promotion of their clearance. Collectively, our results present a novel phenotypic, ontogenic, and molecular definition of liver-MF compartment following acute injury.
Rechnergestützte Dosierung in der Antikoagulationstherapie mit Phenprocoumon
Authors: Cromme L. J. , Salzwedel A. , Taborski U. , Kunath J. , Gäbler F. , Heyne K. , Völler H. , Dissmann R. 
Published: June 2014

SummaryA recently developed multiparameter computer- aided expert system (TheMa) for guiding anticoagulation with phenprocoumon (PPC) was validated by a prospective investigation in 22 patients. The PPC-INR-response curve resulting from physician guided dosage was compared to INR values calculated by “twin calculation” from TheMa recommended dosage. Additionally, TheMa was used to predict the optimal time to perform surgery or invasive procedures after interruption of anticogulation therapy. Results: Comparison of physician and TheMa guided anticoagulation showed almost identical accuracy by three quantitative measures: Polygon integration method (area around INR target) 616.17 vs. 607.86, INR hits in the target range 166 vs. 161, and TTR (time in therapeutic range) 63.91 vs. 62.40 %. After discontinuation of anticoagulation therapy, calculating the INR phase-out curve with TheMa INR prognosis of 1.8 was possible with a standard deviation of 0.50 ± 0.59 days. Conclusion: Guiding anticoagulation with TheMa was as accurate as Physician guided therapy. After interruption of anticoagulant therapy, TheMa may be used for calculating the optimal time performing operations or initiating bridging therapy.
Longitudinal Follow-up of a Cohort of Patients with Incidental Abnormal Magnetic Resonance Imaging Findings at Presentation and Their Risk of Developing Multiple Sclerosis
Authors: Nakamura Mio , Morris Mark , Cerghet Mirela , Schultz Lonni , Elias Stanton 
Published: June 2014

Background: Magnetic resonance imaging (MRI) is widely used in clinical practice, and “abnormal brain MRI” findings often prompt assessment for multiple sclerosis (MS), even when there are no symptoms suggestive of the disease. Despite several studies involving individuals with “radiologically isolated syndrome” (RIS), little is known about what factors might predict future development of MS. The objective of this study was to longitudinally evaluate clinical and MRI characteristics of people who presented to an MS clinic because of incidental abnormal MRI findings but did not have typical symptoms of MS, in order to assess risk factors for developing MS.
Methods: Thirty consecutive patients presenting to an MS clinic for evaluation of abnormal MRI findings were enrolled in the study. Clinical and paraclinical data, including MRI results, were reviewed. Magnetic resonance imaging findings of T2 hyperintensities measuring more than 3 mm in diameter and fulfilling at least three out of four Barkhof criteria, with or without gadolinium-enhancing lesions, were considered to be suggestive of MS.
Results: The median follow-up time was 5.5 years. No participants without MRI findings suggestive of MS were diagnosed with MS (P = .005). Fifteen participants had MRI findings suggestive of MS. Seven of the 15 (47%) were diagnosed with MS on follow-up. Cerebrospinal fluid (CSF) testing results were available for 15 participants. Abnormal results were found in six participants, of whom five (83%) also had MRI findings suggestive of MS. Only two of the nine (22%) participants with normal CSF results (P = .04) had MRI findings suggestive of MS.
Conclusions: In our cohort, none of the participants without MRI findings suggestive of MS developed MS. The participants with MRI findings suggestive of MS were more likely to develop symptoms and MRI changes typical of MS on follow-up.
Analyzing the 2010–2011 La Niña signature in the tropical Pacific sea surface salinity using in situ data, SMOS observations, and a numerical simulation
Authors: Hasson Audrey , Delcroix Thierry , Boutin Jacqueline , Dussin Raphael , Ballabrera‐Poy Joaquim 
Published: June 2014

AbstractThe tropical Pacific Ocean remained in a La Niña phase from mid‐2010 to mid‐2012. In this study, the 2010–2011 near‐surface salinity signature of ENSO (El Niño‐Southern Oscillation) is described and analyzed using a combination of numerical model output, in situ data, and SMOS satellite salinity products. Comparisons of all salinity products show a good agreement between them, with a RMS error of 0.2–0.3 between the thermosalinograph (TSG) and SMOS data and between the TSG and model data. The last 6 months of 2010 are characterized by an unusually strong tripolar anomaly captured by the three salinity products in the western half of the tropical Pacific. A positive SSS anomaly sits north of 10°S (>0.5), a negative tilted anomaly lies between 10°S and 20°S and a positive one south of 20°S. In 2011, anomalies shift south and amplify up to 0.8, except for the one south of 20°S. Equatorial SSS changes are mainly the result of anomalous zonal advection, resulting in negative anomalies during El Niño (early 2010), and positive ones thereafter during La Niña. The mean seasonal and interannual poleward drift exports those anomalies toward the south in the southern hemisphere, resulting in the aforementioned tripolar anomaly. The vertical salinity flux at the bottom of the mixed layer tends to resist the surface salinity changes. The observed basin‐scale La Niña SSS signal is then compared with the historical 1998–1999 La Niña event using both observations and modeling.