bluuebunny/crossref_metadata_2025_split huggingface dataset:
Finding Oil Is Really Hard, Making Money Even Harder
Authors: Rassenfoss Stephen 
Published: April 2020

As ExxonMobil announced discovery after discovery offshore Guyana, it sounded easy.
Beginning with the Liza-1 discovery well, the giant oil company announced 16 successful exploration wells. There were four or five successful wells per year from 2017 through 2019, ending with news of its 16th find in January—pushing its estimated oil in the ground to 8 billion bbl.
For those who found the oil, the evidence they used to pick those drilling targets was hardly clear cut, and it took more than 90 years to get to that point.
“In retrospect it wasn’t obvious, and that was why it took so long,” said Maria Guedez, exploration manager for Guyana and Suriname for ExxonMobil.
While a timeline of the Guyana project includes “initiated oil and gas exploration activities in Guyana in 2008,” the story ExxonMobil presented at the recent AAPG SuperBasins 2020 conference covered exploration starts and stops going back to 1928 by the company’s predecessor, Standard Oil Co.
One slide showed a typewritten report from the 1930s noting the test wells were “salted,” giving the impression of a rich reservoir, even though “there is no evidence of oil.”
But ExxonMobil and other oil companies kept coming back. There were dry holes in the 1970s off nearby Suriname—the eastern extension of the play. They saw some positive signs, but the source rock was judged to be not mature enough to fill the conventional oil deposits needed to justify development.
Finally, in the 1990s ExxonMobil geoscientists looking for new exploration opportunities used what had been learned, plus advanced seismic imaging, a better understanding of the movements of tectonic plates, and some simple analysis to outline a plan that ultimately led to the discovery.
Guedez showed a picture of a simple chart evaluating the pros and cons of the basin with handwritten notes, and a geologic cross section in which a geologist hand-counted layers in shallow and deep waters to identify the elements of a productive play.
“New data and technologies often trigger key insights, but you need to ask the right questions,” Guedez said. “Sometimes you don’t need massive amounts of data to make a difference.”
Executing the concept required developing the ability to drill wells in water 8,000 ft deep and high resolution to seismic that allowed interpreters to see the subtle signs of hydrocarbon-rich stratigraphic traps.
“The places where you have structure, it was hard [to spot anomalies]. Stratigraphic traps are normally just really difficult to explore. It was going to be difficult to hit without having some sort of high-resolution 3D seismic,” Guedez said.
These anomalies are never easy to spot, but she said that compared to her experience in offshore Africa, signs of traps off Guyana were “remarkably subtle.”
So far, they have hit on 89% of the wells drilled. “Once the eyes of the team got fine-tuned to that, they did a good job spotting them,” Guedez said.
Technology Focus: Deepwater Fields (May 2020)
Authors: Iversen Morten 
Published: April 2020

The collapse in upstream investment has wreaked havoc on the deepwater market, leading to rationalization and consolidation. Many of the operators and rig/vessel owners left have been clinging on by their fingertips. The number of rigs operating under contract is still at slump levels of less than 200, down by plus minus 30% from the heyday.
Prophets of doom have argued that there will be no cyclical upturn this time, that conventional offshore oil and gas developments, with the odd exception, have been squeezed out of the cost curve by the rise of tight oil. Yet there are signs of recovery that might breathe life back into the sector.
Deepwater is the only segment expected to grow above 5% next year, spelling a positive uplift for the industry in general.
On a regional level, only Africa, Russia, and South America are expected to see growth or flat development in investments next year, with key players such as Mozambique, Libya, and Mauritania pushing the largest continent’s growth to the highest worldwide at greater than 10%. Unsurprisingly, Brazil, thanks to the Marlim and Mero projects, likely will prop South America up to a predicted almost 6% of growth next year.
However, development of deepwater projects presents a series of challenges, even for the most experienced players. While the industry has gone through a long learning curve and technology advancements, which have helped drive down the costs of deepwater production, players still face a myriad of challenges resulting in lengthy development times for deepwater projects. Therefore, the associated offshore-project risks are expected to hinder the growth of the market studied. The other third of offshore wells drilled are exploration.
There are signs that the rig market will tighten. More brand-new high-spec Generation VI and VII rigs are coming onto the market, but these are replacing retirals or forcing lower-spec rigs into cold stack; net available supply looks set to stay flat. Usage rates for Generation VI and VII rigs could climb from 70% currently to greater than 90% inside 4 years.
Finally, pricing power is set for a return. Rates for new contracts are languishing near the lows reached in 2017.
A Look at the Aasta Hansteen Norwegian Deepwater Spar FPSO
Authors: Feder Judy 
Published: April 2020

This article, written by JPT Technology Editor Judy Feder, contains highlights of paper OTC 29222, “Aasta Hansteen Spar FPSO—A Pioneer in Norwegian Deepwater,” by Torolf Christensen, Stig Arne Witsøe, and Helge Hagen, Equinor, et al., prepared for the 2019 Offshore Technology Conference, Houston, 6–9 May. The paper has not been peer reviewed. Copyright 2019 Offshore Technology Conference. Reproduced by permission.
The complete paper describes the overall project execution of the Aasta Hansteen field development on the Norwegian Continental Shelf (NCS) north of the Arctic Circle. It is the deepest field yet developed on the NCS in 1300 m of water. In a harsh environment, with no other offshore installations in the area, the field is being developed with a spar floating, production, storage, and offloading (FPSO) structure using steel catenary risers and polyester mooring lines.
Business Case
The field is 300 km off the coast of northern Norway and 140 km from the nearest offshore installation. The field was discovered in 1997, with investment decision taken in December 2012 and production begun in December 2018. Total investment in facilities and infrastructure (including pipeline and modifications at Nyhamna) is approximately $7 billion. Equinor operates the field on behalf of its partners, Wintershall (24%), OMV (15%), and ConocoPhillips (10%).
The field’s rich gas is exported through a 482-km-long, 36-in. pipeline to an on-shore processing plant at Nyhamna for further processing to sales gas. From there, the gas is exported to the European market. Stabilized condensate is stored in the spar FPSO and offloaded to shuttle tankers.
The development of the field with the platform facilities and the Polarled pipeline was a strategic decision to open a new gas region in the Norwegian Sea and connect it to Europe by the NCS gas infrastructure. The development solution will serve as a gas hub enabling tie-in of future production from discoveries and prospects in the area. The objective of the Aasta Hansteen development is to maximize the recovery of the Aasta Hansteen reserves and to achieve maximum value creation in the value chain.
Estimated recoverable reserves are 51 billion scm rich gas and 0.6 million scm condensate. The reserves consist of three separate discoveries—Luva, Haklang, and Snefrid Sør—all in the Nise formation and within the same production license.
The development of Aasta Hansteen has been executed as a parallel development of the Polarled pipeline project to establish a new gas transport pipeline from Aasta Hansteen to Nyhamna. The pipeline has several tie-in points from Aasta Hansteen to the Nyhamna gas-processing plant. Snefrid Nord, the first subsea tieback development, is already being developed. The complete paper provides a brief description of the Polarled project.
Genome-wide identification and comparison of differentially expressed profiles of miRNAs and lncRNAs with associated ceRNA networks in the gonads of Chinese soft-shelled turtle, Pelodiscus sinensis
Authors: Ma Xiao , Cen Shuangshuang , Wang Luming , Zhang Chao , Wu Limin , Tian Xue , Wu Qisheng , Li Xuejun , Wang Xiaoqing 
Published: April 2020

Abstract
Background: The gonad is the major factor affecting animal reproduction. The regulatory mechanism of the expression of protein-coding genes involved in reproduction still remains to be elucidated. Increasing evidence has shown that ncRNAs play key regulatory roles in gene expression in many life processes. The roles of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) in reproduction have been investigated in some species. However, the regulatory patterns of miRNA and lncRNA in the sex biased expression of protein coding genes remains to be elucidated. In this study, we performed an integrated analysis of miRNA, messenger RNA (mRNA), and lncRNA expression profiles to explore their regulatory patterns in the female ovary and male testis of Pelodiscus sinensis.Results: We identified 10 446 mature miRNAs, 20 414 mRNAs and 28 500 lncRNAs in the ovaries and testes, and 633 miRNAs, 11 319 mRNAs, and 10 495 lncRNAs showed differential expression. A total of 2 814 target genes were identified for miRNAs. The predicted target genes of these differentially expressed (DE) miRNAs and lncRNAs included abundant genes related to reproductive regulation. Furthermore, we found that 189 DEmiRNAs and 5 408 DElncRNAs showed sex-specific expression. Of these, 3 DEmiRNAs and 917 DElncRNAs were testis-specific, and 186 DEmiRNAs and 4 491 DElncRNAs were ovary-specific. We further constructed complete endogenous lncRNA-miRNA-mRNA networks using bioinformatics, including 103 DEmiRNAs, 636 DEmRNAs, and 1 622 DElncRNAs. The target genes for the differentially expressed miRNAs and lncRNAs included abundant genes involved in gonadal development, including Wt1, Creb3l2, Gata4, Wnt2, Nr5a1, Hsd17, Igf2r, H2afz, Lin52, Trim71, Zar1, and Jazf1.Conclusions: In animals, miRNA and lncRNA as master regulators regulate reproductive processes by controlling the expression of mRNAs. Considering their importance, the identified miRNAs, lncRNAs, and their targets in P. sinensis might be useful for studying the molecular processes involved in sexual reproduction and genome editing to produce higher quality aquaculture animals. A thorough understanding of ncRNA-based cellular regulatory networks will aid in the improvement of P. sinensis reproductive traits for aquaculture.
Survival and prognostic factor analyses in malignant giant cell tumour of bone
Authors: Zhang Jin , Wang Xin , Lin Feng , Xu Guijun , Wu Haixiao , Duan Jincai , Mao Min , Zhang Chao 
Published: May 2020

Abstract
Background: The characteristics and survival of patients with malignant giant cell tumour of bone (GCTB) have not been investigated thoroughly due to the rarity of the disease. We evaluated these factors in a large cohort in the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database.Methods: Data from patients who were diagnosed with malignant GCTB from 1975 to 2016 were extracted from the SEER database. The overall survival (OS) was calculated by Kaplan–Meier analysis, and intergroup differences were tested by the log-rank test. Univariate and multivariate Cox proportional hazard regression analyses were conducted to identify the independent survival factors.Results: A total of 325 patients with malignant GCTB were included. The overall 1-, 5-, and 10-year survival rates were 94.3% (95% CI: 91.7-96.8), 82.3% (95% CI: 77.9-86.6), and 80.1% (95% CI: 75.4-84.7), respectively. A potential non-linear J-shaped dose–response relationship between the age or diagnosis year and survival were found. Multivariate Cox regression showed poor survival in patients with age from 35 to 60 years (hazard ratio (HR) =9.99, 95% CI: 1.34-74.80, P=0.025), age older than 60 years (HR=62.03, 95% CI: 7.94-484.38, P<0.001), with stage T2 disease (HR=4.85, 95% CI: 1.52-15.47, P=0.008), with stage T3 disease (HR=6.09, 95% CI: 1.03-36.23, P=0.047), and with distant tumours (HR=2.76, 95% CI: 1.14-6.65, P=0.024), and extraskeletal sites (HR=3.33, 95% CI: 1.02-10.85, P=0.046).Conclusions: This large population-based series described the clinical characteristics of malignant GCTB. Patients with stage T2/3disease, distant disease and extra-skeletal sites had more odds to be with worse survival. The elder age than 34 years had a gradually increased risk for survival.
Primary surgery versus no surgery in synchronous metastatic breast cancer: Patient-reported Quality-of-Life outcomes of the prospective randomized multicenter ABCSG-28 Posytive Trial
Authors: Bjelic-Radisic Vesna , Fitzal Florian , Knauer Michael , Steger Guenther , Egle Daniel , Greil Richard , Schrenk Peter , Balic Marija , Singer Christian , Exner Ruth , Soelkner Lidija , Gnant Michael 
Published: April 2020

Abstract
Background: The ABCSG-28 trial compared primary surgery followed by systemic therapy versus primary systemic therapy without surgery in patients with de novo stage IV BC. The present report describes QoL results of this trial. Methods: 90 patients with primary operable MBC were randomised to surgery of the primary tumor followed by systemic therapy or to primary systemic therapy without surgery. QoL analyses covering the results at baseline, 6,12,18 and 24 months follow up of 79 (88%) patients, was assessed with the EORTC QLQ-C30 and QLQ-BR23 questionnaires. Results: There were no statistically significant differences in any of the scales of the QLQ-C30 and QLQ-BR23 questionnaires between the two groups over the time. Baseline global health status and physical functioning were predictors for OS (patients with a higher score lived longer (p=0.0250, p=0.0225; p=0.0355, p=0.0355)). Global health status, social functioning scale, breast symptoms and future perspective were predictors for longer TTPd (p=0.0244; p=0.0140, p=0.020; p=0.0438, p=0.0123). Patients in both arms reported significant improvement on the emotional functioning scale. Cognitive functioning decreased over time in both groups. Younger women had clinically relevant better physical and sexual functioning scores (p=0.039 and 0.024). Conclusion: Primary surgery does not improve nor alter QoL of patients with de novo stage IV BC. Global health status and physical functioning were predictors for OS and could be use as additional marker for prediction of OS and TTTd in patients with de novo stage IV BC. Trial registration: The trial is listed on clinicaltrial.gov (NCT01015625)
Development of the Prototype Concise Safe Systems Checklist Tool for General Practice
Authors: Litchfield Ian J , Spencer Rachel , Bell Brian , Avery Anthony , Perryman Katherine , Marsden Kate , Greenfield Sheila , Campbell Stephen 
Published: April 2020

Abstract
Background In the course of producing a patient safety toolkit for primary care, we identified the need for a concise safe-systems checklist designed to address areas of patient safety which are under-represented in mandatory requirements and existing tools. This paper describes the development of a prototype checklist designed to be used in busy general practice environments to provide an overview of key patient safety related processes and prompt practice wide-discussion. Methods An extensive narrative review and a survey of world-wide general practice organisations were used to identify existing primary care patient safety issues and tools. A RAND panel of international experts rated the results, summarising the findings for importance and relevance. The checklist was created to include areas that are not part of established patient safety tools or mandatory and legal requirements. Four main themes were identified: information flow, practice safety information, prescribing, and use of IT systems from which a 13 item checklist was trialled in 16 practices resulting in a nine item prototype checklist, which was tested in eight practices. Qualitative data on the utility and usability of the prototype was collected through a series of semi-structured interviews.Results In testing the prototype four of nine items on the checklist were achieved by all eight practices. Three items were achieved by seven of eight practices and two items by six of eight practices. Participants welcomed the brevity and ease of use of the prototype, that it might be used within time scales at their discretion and its ability to engage a range of practice staff in relevant discussions on the safety of existing processes. The items relating to prescribing safety were considered particularly useful. Conclusions As a result of this work the concise patient safety checklist tool, specifically designed for general practice, has now been made available as part of an online Patient Safety Toolkit hosted by the Royal College of General Practitioners. Senior practice staff such as practice managers and GP partners should find it a useful tool to understand the safety of less explored yet important safety processes within the practice.
A univariable and multivariable analysis of right censored time-to-event data based on restricted mean survival time: A combination with traditional survival methods.
Authors: Huang Qiao , Lyv Jun , Li Bing-hui , Ma Lin-lu , Deng Tong , Zeng Xian-Tao 
Published: April 2020

Abstract
Background Hazard ratio is considered as an appropriate effect measure of time-to-event data. However, hazard ratio is only valid when proportional hazards (PH) assumption is met. The use of the restricted mean survival time (RMST) is proposed and recommended without limitation of PH assumption. Method 4405 osteosarcomas were captured from Surveillance, Epidemiology and End Results Program Database. Traditional survival analyses and RMST-based analyses were integrated into a flowchart and applied for univariable and multivariable analyses, using hazard ratio (HR) and difference in RMST (survival time lost or gain, STL or STG) as effect measures. The relationship between difference in RMST and HR were explored when PH assumption was and was not met, respectively. Results In group comparison and univariable regressions, using difference in RMST calculated by Kaplan-Meier methods as reference, pseudo-value regressions (R2=0.99) and inverse probability of censoring probability (IPCW) regressions with group-specific weights (R2=1.00) provided more consistent estimation on difference in RMST than IPCW with individual weights (R2=0.09). In multivariable analysis, age (HR:1.03, STL: 3.86 months), diagnosis in 1970~1980s (HR:1.39 STL:27.49 months), metastasis (HR:4.47, STL: 202 months), surgery (HR:0.58, SLG:35.55 months) and radiation (HR:1.46, SLT:44.65 months) met PH assumption and were main independent factors for overall survival. In both univariable and multivariable variables, a robust negative logarithmic linear relationship between HRs estimated by Cox regression and differences in RMST by pseudo-value regressions was only observed when PH assumption was hold. Conclusion The flowchart will be intuitive and helpful to instruct appropriate use of RMST based and traditional methods. RMST-based methods provided an absolute effect measure to inspect effects of covariates on survival time and promote evidence communication with HR. Difference in RMST should be reported with hazard ratio routinely.
Delta Neutrophil Index as a Predictive and Prognostic Factor for Candidemia patients: A Matched Case-Control Study
Authors: Park So Yeon , LEE JIN SEO , Oh Jihyu , Park Ji-Young 
Published: April 2020

Abstract
Background: Delayed antifungal therapy for candidemia leads to increased mortality. Differentiating bacterial infection from candidemia in systemic inflammatory response syndrome (SIRS) patients is complex and difficult. The Delta Neutrophil Index (DNI) has recently been considered a new factor to distinguish infections from non-infections and predict the severity of sepsis. We aimed to assess if the DNI can predict and provide a prognosis for candidemia in SIRS patients. Methods: A matched case-control study was conducted from July 2016 to June 2017 at Kangdong Sacred Heart Hospital. Among patients with a comorbidity of SIRS, those with candidemia were classified as the case group, whereas those with negative blood culture results were classified as the control group. The matching conditions included age, blood culture date, and SIRS onset location. Multivariate logistic regression was performed to evaluate DNI as a predictive and prognostic factor for candidemia.Results: The 140 included patients were assigned to each group in a 1:1 ratio. The DNI_D1 values measured on the blood culture date were higher in the case group than in the control group (p<0.001). The results of multivariate analyses confirmed DNI_D1 (odds ratio [ORs] 2.138, 95% confidential interval [CI] 1.421-3.217, p<0.001) and Candida colonization as predictive factors for candidemia. The cutoff value of DNI for predicting candidemia was 2.75%. The area under the curve for the DNI value was 0.804 (95% CI, 0.719-0.890, p<0.001), with a sensitivity and specificity of 72.9% and 78.6%, respectively. Analysis of 14-day mortality in patients with candidemia showed significantly higher DNI_D1 and DNI_48 in the non-survivor group than in the survivor group.Conclusions: DNI was identified as a predictive factor for candidemia in patients with SIRS and a prognostic factor in predicting 14-day mortality in candidemia patients. DNI, along with clinical patient characteristics, was useful in determining the occurrence of candidemia in patients with SIRS.