bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solutions to Increase the Economic Attractiveness of Offshore Projects - Petrobras Experience in Subsea Design
Authors: Valente Oazen Eduardo , Duarte Dos Santos Thiago , Rodrigues Cabral Gabriel , Garcia Do Prado Vinicius 
Published: April 2019

Offshore oil development projects are complex and require high capital investment. The application of methodologies that seek optimization of economic parameters of projects became particularly important since 2014, when oil barrel prices plummeted. At that moment, some projects required modifications to regain economical attractivity. The recovery of project profitability depended on the break-even oil price criterion fulfillment (typically USD 40-45) among other requirements.
This paper presents a methodology developed by Petrobras to increase the profitability of offshore projects in conceptual design phase while meeting the technical and safety minimum requirements. Successful solutions provided by the Petrobras team, enabled through this methodology, to make more than 15 projects economically viable are presented. The solutions include phased development, reuse of flexible lines from declining production wells, application of new technologies (including boosting and processing), use of innovative subsea architectures, procedures to increase ramp-up speed, long tie-backs, etc. This article is focused on subsea engineering solutions.
EWT Program - Enabling Optimization and Speed Up for Libra Block Production Systems Development in Ultra-Deepwater
Authors: Costa Francisco Ferreira , Caloba Guilherme Marques , Botsman Erika , Kaercher André Loeblein , Lia Lucas Silva 
Published: April 2019

Abstract
The paper uses a case study approach to present the challenges to develop a large and thick oil carbonate reservoir, full of opportunities but also of uncertainties. Additionally, Libra block development is under a Production Share Contract that was award to a Consortium where Petrobras is the operator in partnership with Shell, Total, CNOOC and CNPC. The paper will briefly present the de-risking plan and detail the EWT Program implementation and the way it is helping the full field development, which consists of four mega ultra deepwaters projects.
Extend Well Test EWT Libra Project Overview and Technological Highlights
Authors: Rovina Paulo Sergio , Valença Cláudio J. G. M. , Passarelli Fábio Menezes , Balint Stephen William 
Published: April 2019

Abstract
This paper uses a case study approach to present the challenges to develop a large and thick oil carbonate reservoir that is full of opportunities and uncertainties. The Libra block, located in Santos Basin ultra-deep water, in Brazil, has been developed under a Production Sharing Contract that was awarded to a Consortium where PETROBRAS is the operator in partnership with SHELL, TOTAL, CNOOC Limited and CNPC. This document will briefly present the de-risking plan, and detail the EWT Program implementation and its impact on the Mero area development, which consists of up to 4 (four) mega projects and altogether represents over 20 billion dollars in CAPEX investment. In addition, the results will show how the achievements achieved by the EWT project provided an extensive technological legacy to the offshore oil & gas industry.
Strain-Life Fatigue Analysis for HPHT Equipment: Theory to Validation
Authors: Aguilar Alvaro , Pathak Parth D , Stevens James E , Foley Claire R 
Published: April 2019

Abstract
Subsea equipment covered by the API Spec 17 subcommittee has had limited focus on assessing fatigue life because of external environmental loads using traditional analysis methods. With the current trend of high-pressure, high-temperature (HPHT) development, the industry is migrating to an era of modern analysis methods with complex material testing programs to assess potential fatigue life impacts due to such high-pressure and -temperature exposures as well. This paper presents an approach and an example of a multiaxial strain-life analysis method that meets the provided HPHT design guidelines of API Technical Report 17TR8.
The paper bridges the gap between theory and practicality in strain-life-based fatigue analysis and presents a robust process developed for HPHT nickel alloy components, which are part of the subsea 20,000-psi vertical monobore subsea tree. The endeavor includes strategizing for required material tests in environment, actual material testing, followed by material data processing, which includes statistical corrections and extraction of parameters necessary for efficient fatigue analysis. The components are then analyzed in finite-element analysis (FEA) with typical loading sequences as seen in its life of field. Finally, the FEA results are postprocessed using the critical plane approach for all nodes in the model. The governing equations are presented throughout the analysis to enable readers to develop their own results.
The 20,000-psi vertical monobore tree fatigue analysis depends on the operations forecasted for its life cycle. Using the expected load histogram, a series of pressure and thermal analyses were executed to produce cycles to failure. Implementing the Palmgren–Miner's rule enabled obtaining the total damage produced by factory acceptance tests total field life shut-ins, and flow-in pressure cycles. This not only serves as verification that the required safety factor is met per API Technical Report 17TR8 but also enables making engineering assessments of "what-if" operations. In this sense, a change or addition of an operation will lead to a simple recalculation of fatigue damage without requiring performing the analysis from the ground up. The method also allows for computation of cycles to failure for a pressure range when the other pressure ranges and conditions don't change.
In addition to the life cycle calculation, the method evaluates the damage of all nodes, which produces full-contour plots. The contour plots, in addition to displaying the hot-spot locations, when used with structural analysis results, enable the engineer to assess areas of improvement and product optimization. The method proposed gives an effective way to communicate and recommend the design life capabilities of a product to the operator to predict life expectancy for combinations of expected load scenarios.
Design of New Classes of Flexible Hang-Offs for Rigid Risers
Authors: Wajnikonis Christopher John 
Published: April 2019

Abstract
This paper introduces new classes of hang-offs for Steel Catenary Risers (SCRs) and Steel Lazy Wave Risers (SLWRs). Bending and tension loads are totally decoupled in the riser hang-offs presented. The new hang-offs can be designed for any temperature or pressure that can be supported by SCRs or SLWRs. The novel devices have rotational stiffnesses considerably lower than are those of Flexible Joints or Titanium Stress Joints (TSJs). This results in fatigue life improvements in the upper regions of risers and in supporting vessel structure. The new hang-offs can be easily designed for greater riser deflections than are those feasible with traditional hang-offs. Methodology used in preliminary design is outlined. Simplified preliminary calculations are included and results of non-linear (large deflection) Finite Elements Analyses (FEAs) are provided. This work highlights possible practical implications of the new designs for the envelopes of the use of SCRs and SLWRs.
Influence of the Mean Load on the Fatigue Performance of Mooring Chains
Authors: Fernández Jonathan , Arredondo Alberto , Storesund Walter , González Javier Jesús 
Published: April 2019

Abstract
Whilst it is known that mean stress has an effect on the fatigue endurance of steel components, this effect is not considered when designing mooring system components. The S-N and T-N fatigue design curves for mooring chain in the standards are based on tests carried out at a single mean load, which is 20% of the chain minimum breaking load (MBL), and these curves are used to compute the damage of all load cycles regardless of their mean value.
Lately it has been found that the effect of the mean load can be larger than probably expected, and that mooring chains exhibit a significant increase of fatigue capacity when cyclically loaded at reduced mean load.
In the majority of the floating units, the pre-tension of the moorings without environmental loads is below or well below 15% of the chain MBL, and most, if not all, of the in-service damage is produced at mean loads below 20% MBL. This in practice results in additional conservatism to the fatigue life computed using the existing design curves. Some deepwater units, subjected to high pre-tension level, can experience some or relevant damage occurring at mean loads above 20% MBL, which would be underestimated with the present design approach.
The paper provides an insight on the effect of the mean load on the fatigue endurance of mooring chains and quantifies this dependency based on a large number of fatigue tests carried out on different chain diameters between 70 and 171 mm, different grades, and different mean loads ranging between 7% and 20% of the MBL of the tested chains.
The Smith-Watson-Topper (SWT) mean stress correction model is used to transform the stress state of the tested chains into different stress states associated to different mean loads. Then regression analyses are performed and correction functions derived for the design curves of both S-N and T-N approaches to account for the mean load while keeping the same confidence of the existing curves.
Digital Twin - Engineering with the Human Factor in the Loop
Authors: Geselschap Catina , Meskers Geert , Dijk Radboud Van , Winsen Ivan Van 
Published: April 2019

Abstract
The Digital Twin, Heerema Simulation Center (HSC), is able to capture the offshore behavior in a realistic real-time digital environment with high fidelity hydrodynamics and physics and real operator stations. This digital tool completely changed engineering in all phases of the project life cycle since its first use in 2015. Its unique capacity is to ‘Engineer with the Human Factor in the loop’ independent if this Human Factor is the client, designer, fabricator, marine warranty surveyor or the offshore operator.
In the conventional engineering tools the Human Factor cannot be included and in the conventional engineering process the preparation is done by engineers without much involvement of the operators. It is as if engineering and execution are separate worlds. Being able to bring these worlds together efficiently in an early stage has already led to an efficiency improvement for all parties (i.e. client, fabricator and offshore operator) involved and has improved the Operational Excellence offshore.
In this paper the results of three simulated cases will be described to explain the way the Digital Twin is used for different purposes and objectives and what sort of results can be achieved from ‘Engineering with the Human Factor in the loop’.
The Digital Twin is an exceptional tool in our Digital Journey that speeds up the process of implementing changes for a more efficient and safer offshore world.
Constraints on the Timing of Continental Rifting and Oceanic Spreading for the Mesozoic Gulf of Mexico Basin
Authors: Pascoe Rob , Nuttall Peter , Dunbar David , Bird Dale 
Published: April 2019

Abstract
The Mesozoic Gulf of Mexico Basin is considered in this discussion as the set of contiguous, Triassic and Jurassic sub-basins directly involved in the counterclockwise rotation of the Yucatan Block from North America in the Late Jurassic. The rifting and seafloor spreading history of the basin is less well understood than analogous salt basins of the Atlantic margins, largely because the base salt surface is significantly deeper and has hereto widely been considered acoustic basement.
In 2012, 17,000 km of 2D PSDM reflection seismic data (SuperCache) were acquired across the deep water of the U.S. Gulf of Mexico. The unique acquisition configuration of long-offset, powerful source, and deep-tow of both source and receivers was designed to optimize the imaging of the presalt architecture of the basin to a depth of 40 km. On these seismic data, the base of the salt and its correlative unconformity, continental and oceanic basement, and the Moho are evident. In combination with vintage, reflection seismic data, shipboard and regional gravity data, and regional refraction profiles, a crustal interpretation has been extended to the greater Gulf of Mexico Basin.
The continental crustal architecture is described in terms of crustal thinning: from low (&lt;30%) to transitional (&gt;70%). Synkinematic sequences are recognized within the Late Triassic to the Middle Oxfordian (~70 my). The final break-up phase occurred within 15 my, ending with a basin-wide open marine transgression and initial emplacement of oceanic crust at 160±1 Ma; continued extension may have occurred in the eastern part of the basin in the latest Jurassic. The basin margins are considered to be intermediate between magmapoor and volcanic end-members. The ocean crust tapers from a maximum width of 700 km in the west, where it is anomalously thin, to anomalously thick as it approaches the pole of rotation in the Straits of Florida. The architecture of extinct spreading valleys and fracture zones is analogous to the modern, slow spreading mid-Atlantic ocean, suggesting that spreading continued until the latest Jurassic (~142 Ma), possibly as late as within the early Cretaceous (~132 Ma).
Triassic-Jurassic Provenance Signatures in the Nascent Eastern Gulf of Mexico Region from Detrital Zircon Geochronology
Authors: Weislogel Amy L. , Wiley Kory S. , Bowman S. , Robinson Delores M. 
Published: April 2019

Abstract
By comparing new detrital zircon provenance analysis of Triassic synrift sediments from the Tallahassee graben (FL), the South Georgia rift basin (GA), and Deep River rift basin (NC) with our previous detrital zircon provenance data for the Jurassic Norphlet Formation erg in the Eastern Gulf of Mexico, we have developed a regional model of Triassic-Jurassic erosion and sediment transport. In the Eastern Gulf of Mexico, detrital zircon ages observed in Triassic synrift clastics from the Tallahassee graben and southern South Georgia rift system contain not only Gondwanan-aged and Grenville-aged zircon grains but also an abundance of Paleozoic detrital zircon grains, reflecting sediment influx from rocks associated with the Paleozoic orogens of eastern Laurentia. Although Paleozoic detrital zircon grains are present in the younger Norphlet deposits, they are less abundant than in Triassic rift sediments. In southwest Alabama, the most abundant detrital zircon age population in the Norphlet Formation is Grenville-aged (950-1,250 Ma). In the Conecuh embayment of southeastern AL and western FL panhandle, Norphlet samples show a marked decrease in Grenville detrital zircon and an increase in 525-680 Ma zircon ages, interpreted to represent influx from rocks associated with the Gondwanan Suwannee terrane. In the Apala-chicola Basin, the proportion of Gondwanan zircon ages increases to nearly 40% of the total population and Grenville-aged grains constitute just ~20% of the population. We suggest that the difference between Triassic and Jurassic detrital zircon signatures in the Eastern Gulf of Mexico reflects significant unroofing of Paleozoic rocks during early Mesozoic rifting of the easternmost Eastern Gulf of Mexico, possibly including rocks equivalent with those exposed in the Talladega slate belt units. Subsequent erosion of rift-flanking highlands to expose older Gondwanan and Grenville rocks and/or input from northern sediment sources supplied the older Grenville-aged detrital zircon grains present in the Norphlet erg in the area to the west and within the Conecuh embayment.
Accreditation Council for Graduate Medical Education Self-Study for Pathology: One Institution's Experience and Lessons Learned
Authors: Maniar Kruti P. , Arva Nicoleta , Blanco Luis Z. , Mao Qinwen , Morency Elizabeth G. , Rodriguez Raven , Wolniak Kristy , Yaseen Nabeel R. , Nayar Ritu 
Published: April 2019

Context.—
The Accreditation Council for Graduate Medical Education (ACGME) established a new system for accreditation of residency and fellowship programs in 2013. One key aspect of the Next Accreditation System is the 10-year self-study, which requires programs to conduct a comprehensive self-evaluation, including development of program aims and analysis of strengths, weaknesses, and environmental context, in order to plan improvements and take the program to the next level.

Objective.—
To provide a review of the recent changes and current state of ACGME accreditation, with a focus on the new 10-year self-study, and to share our institution's experience with conducting the first self-study of our pathology residency and accredited fellowship programs in 2018.

Data Sources.—
Review of English-language literature, published resources from the ACGME, and materials/data from our department's 2018 self-study.

Conclusions.—
The self-study process now required for ACGME accreditation is a useful way to assess program strengths and weaknesses in the context of current environmental and institutional factors, and helps develop an effective framework for improvements geared at achieving program aims and taking the program to the next level. Additionally, conducting residency and fellowship self-studies together allows for collaboration, effective use of shared resources, and the development of a cohesive educational mission.
Modulation of Hormonal, Oxidative Stress and Fatty Acids Profiling in Response to Glutamine and Chromium in Diabetic Rats
Authors: Khan Jehan A. 
Published: April 2019

Background: Fatty acids profiling of diabetes may be helpful in early diagnosis and management of diabetic. Chromium is a trace element and important cofactor for many anti-oxidant enzymes as superoxide dismutase. Glutamine is semi essential amino acid and reported to improve endothelial function, decrease blood pressure, and vasodilator. This study investigated fatty acids profiling in diabetic rats and their response to administration of glutamine and chromium.
Methods: Fifty male albino rats were divided into 2 groups as following: GPI (10 rats); Control group. GP II (40 rats) were injected alloxan (75 mg /kg) i.p. for six consecutive days for induction of diabetes. Diabetic rats were divided into four groups: GP II: (Untreated diabetic): GP III: Rats were given orally with L-glutamine (100 mg/kg).GP IV: Rats were given with Chromium chloride (30 µg/ kg) ip. GP IV: Rats were given Glutamine and Chromium. After 6 weeks. Sera were used for the determination of Nitric oxide (NO), malondialdhyde (MDA), total antioxidants, insulin, glucagon, HA1C and fatty acids profile.
Results: Data obtained showed that, diabetic rats treated with glutamine and chromium restore the levels of hormones, HA1C, NO and MDA better than individual treatment (p<0.01) compared with untreated diabetic (p<0.001). A significant elevation of saturated fatty acids in diabetic and reduced unsaturated FA compared with control. Combination treatment reversed this ratio. This may explain increased insulin sensitivity in treated rats compared with untreated.
Conclusion: It was concluded that, Glutamine combined with chromium increased insulin sensitivity and recovery pancreatic efficacy in insulin production. Administration of glutamine or chromium reduced HA1c, the mechanisms involved explored the potential of these compounds in control fatty acids contents and management of diabetic.
Highly Stretchable Supercapacitors via Crumpled Vertically Aligned Carbon Nanotube Forests
Authors: Cao Changyong , Zhou Yihao , Ubnoske Stephen , Zang Jianfeng , Cao Yunteng , Henry Philémon , Parker Charles B. , Glass Jeffrey T. 
Published: April 2019

AbstractStretchable supercapacitors have received increasing attention due to their broad applications in developing self‐powered stretchable electronics for wearable electronics, epidermal and implantable electronics, and biomedical devices that are capable of sustaining large deformations and conforming to complicated surfaces. In this work, a new type of highly stretchable and reliable supercapacitor is developed based on crumpled vertically aligned carbon nanotube (CNT) forests transferred onto an elastomer substrate with the assistance of a thermal annealing process in atmosphere environment. The crumpled CNT‐forest electrodes demonstrated good electrochemical performance and stability under either uniaxial (300%) or biaxial strains (300% × 300%) for thousands of stretching–relaxing cycles. The resulting supercapacitors can sustain a stretchability of 800% and possess a specific capacitance of 5 mF cm−2 at the scan rate of 50 mV s−1. Furthermore, the crumpled CNT‐forest electrodes can be easily decorated with impregnated metal oxide nanoparticles to improve the specific capacitance and energy density of the supercapacitors. The approach developed in this work offers an alternative strategy for developing novel stretchable energy devices with vertically aligned nanotubes or nanowires for advanced applications in stretchable, flexible, and wearable electronic systems.
A Diene‐Containing Noncanonical Amino Acid Enables Dual Functionality in Proteins: Rapid Diels–Alder Reaction with Maleimide or Proximity‐Based Dimerization
Authors: St. Amant Andre H. , Huang Fengying , Lin Jia , Rickert Keith , Oganesyan Vaheh , Lemen Daniel , Mao Shenlan , Harper Jay , Marelli Marcello , Wu Herren , Gao Changshou , Read de Alaniz Javier , Christie R. James 
Published: April 2019

AbstractHere, we describe a diene‐containing noncanonical amino acid (ncAA) capable of undergoing fast and selective normal electron‐demand Diels–Alder (DA) reactions following its incorporation into antibodies. A cyclopentadiene derivative of lysine (CpHK) served as the reactive handle for DA transformations and the substrate for genetic incorporation. CpHK incorporated into antibodies with high efficiency and was available for maleimide conjugation or self‐reaction depending on position in the amino acid sequence. CpHK at position K274 reacted with the maleimide drug‐linker AZ1508 at a rate of ≈79 m−1 s−1 to produce functional antibody–drug conjugates (ADCs) in a one‐step process. Incorporation of CpHK at position S239 resulted in dimerization, which covalently linked antibody heavy chains together. The diene ncAA described here is capable of producing therapeutic protein conjugates with clinically validated and widely available maleimide compounds, while also enabling proximity‐based stapling through a DA dimerization reaction.
A Facile Enantioselective Alkynylation of Chromones
Authors: DeRatt Lindsey G. , Pappoppula Mukesh , Aponick Aaron 
Published: April 2019

AbstractThe first catalytic enantioselective alkynylation of chromones is reported. In this process, chromones are silylated to form silyloxybenzopyrylium ions that lead to silyl enol ethers after Cu‐catalyzed alkyne addition using StackPhos as a ligand. The outcome of the reaction is impacted by distal ligand substituents with differing electronic character and it was found that successful reactions could be achieved with different ligand congeners by using different solvents. This sequence enables access to different products by protonation or further functionalization, thus increasing complexity in a divergent manner. The transformation is high yielding over a broad scope to provide a variety of useful chromanones in high enantioselectivity.