bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tandem Dry Gas Seals Design and Maintenance Considerations for Enhanced Reliability and Performance
Authors: Kamal Girish 
Published: November 2019

Abstract
Dry Gas Seals (DGS) for centrifugal compressors exist in the process industry for the last almost thirty years and almost all the compressor units operating in the industry today are equipped with Dry Gas Seals. High operating and maintenance costs, unreliability and hazardous characteristics inherent with the conventional lubricated shaft sealing systems have resulted in widespread utilization of the DGS and their associated sealing systems.
This paper shall cover the design considerations including best operation and maintenance practices to enhance dry gas seals operating life and performance including: ▪Major factors affecting Dry Gas seals service life▪Seal Gas supply and control requirements▪Primary Gas seal venting and health monitoring▪Secondary Gas seal venting and health monitoring▪Separation Gas supply control systems and health monitoring▪Recommended Alarm, Shutdown and Start-Permissive conditions
Processing Challenges and Solutions for Seismic Reservoir Characterization With Wide-Azimuth OBC Seismic Data, Offshore Abu Dhabi, UAE
Authors: Miyamoto Hiroki , Almheiri Afra Naser , Kojima Keitaro , Shibasaki Toshiaki , Bellah Samir , Aljasmi Sami , Mahgoub Mohamed , Cambois Guillaume , Paul Subhrankar , Khakimov Oleg , Barajas Carlos 
Published: November 2019

Abstract
Seismic processing is expected to deliver a reliable product for seismic structure interpretation and reservoir characterization to support subsequent reservoir modeling and drilling operation. 3D OBC wide-azimuth (WAZ) seismic data has a significant advantage in this respect, since it contains large offset and wide azimuth information, which can be utilized for amplitude versus offset (AVO) and amplitude versus azimuth (AVAz) analysis respectively. However, these advanced studies require area-specific data processing efforts in this region for strong linear noise, multiple noise, designature uncertainty etc. Seismic data re-processing was newly conducted in pre-stack time migration (PrSTM) sequence to overcome such technical challenges. Surface-wave noise attenuation was achieved by 2D and 3D model-based dispersive energy attenuation and multi-pass structure oriented filtering in pre-stack and post-stack stages. Source-side deghosting highlighted a low frequency residual bubble and was followed by another pass of de-bubbling based on a smooth spectrum assumption. Shallow water reverberation was minimized by 3D deconvolution and high-resolution radon demultiple. 5D regularization and interpolation with trace densification provided evenly populated traces for each angle and azimuth sectors. Intensive signal preservation protected diffraction energy and resulted in better fault imaging than the vintage processing outcome. Both the vintage and the re-processed seismic data were evaluated in quantitative manners to compare with each other. Angle stacks from the re-processing showed more reasonable response for AVO analysis. Azimuth stacks showed stable S/N ratio leading to higher confidence in azimuthal anisotropy analysis. All these seismic deliverables enable accurate elastic property estimation and detail fault interpreation at target reservoir intervals. The novelty of the proposed workflow is to overcome common technical problems with targeted noise and multiple reduction focusing on angle / azimuth stacks. It unlocks advanced geophysical study for carbonate reservoir in shallow water areas. Processing deliverables will be fully utilized in fault interpretation, AVO and AVAz analysis and will support the forthcoming field development activity.
New Corrosion Growth Model Based on Pipeline Intelligent Pigging Data - Correlating Corrosion Defects Numbers with their Depth
Authors: Trojette Mohamed Zouheir , Zebibi Anouar , Hammadi Abdallah , Hosani Khalid 
Published: November 2019

Abstract
As part of their integrity management system, Oil and Gas operators carry out internal inspection of their pipelines by intelligent pigging. State of the art MFL and UT inspections are used to detect and accurately size the defects, which are present in the pipeline. The predominant type of defects reported is due to internal corrosion.
It is well established that corrosion is a naturally occurring phenomena. When the conditions are right for corrosion to develop, it starts by a single defect or very few defects which are shallow. Then as the pipeline is operated and corrosion further develops the defects increase in size and numbers.
This paper review several intelligent pigging reports data, and analyze the reported defects in terms of numbers and depth for several pipelines, in order to establish a correlation (mathematical model) between the number of internal corrosion defects and their depth. Defects counts will be made and equations will be developed for several pipelines. These equations will basically establish the number of defects as a function of their depth or vice versa.
More over when multiple intelligent pigging runs on same line are available, these derived equations will be compared with the objective to establish a novel model to determine corrosion growth rate in a non-conventional manner. In fact the models (# of defects and their depth equation) established for different inspections will be compared and a corrosion rate model establishing the increase in number of features and their number over time will be thereafter derived.
How Rethinking the Drilling System, from the Drillbit to the Drillstring and the Drilling Fluid Addressed a Threatening Casing Wear and Turned a Difficult 6-in. Section into a Perfect 6-in. Sidetrack
Authors: Labrousse Sébastien , Guner Hakan , Kauffmann Carlos , Caycedo Alberto , Opsahl Jørn , Atallah Rawad , Hatleseth Tore Andreas , Moldekleiv Rune , Nokland Magnar , Andreassen Ørjan , Nyborg Benjamin 
Published: November 2019

Abstract
The purpose of the paper is to present how an integrated solution was designed to turn a challenging 6-in. section into a successful 6-in. production sidetrack in Norway. A threatening casing wear issue caused by the combination of slow progress and localized dogleg was addressed successfully with a complete redesign of the drilling system.
A 6-in. pilot section suffered slow progress due to low rate of penetration and tool failures. Significant amount of metal swarf was recovered while drilling. A casing wear log quantified the wear in the 9 7/8-in. casing, and this led to questioning the feasibility of the planned 6-in. production sidetrack. Operator, rig contractor and integrated services provider worked together to find a solution.
First, a detailed study of the wear was performed. A wear log was run, and the casing wear was quantified. Casing wear simulations were then calibrated based on wear logs and it appeared feasible to drill the 6-in. sidetrack if a minimum rate of penetration and a maximum number of revolutions were respected.
Second, the drilling system was optimized to ensure faster progress. This was done thanks to the learnings from the pilot section. The mud system was changed, and a lower density was used to increase the rate of penetration. The drillbit was optimized based on the limited wear seen in the bits used in the pilot section. As it was more aggressive, the perceived risk of downhole tool failure was mitigated with the use of an anti-stall tool.
Finally, to reduce the incremental wear from the sidetrack operation, casing protectors and lubricants were run. Also, the planned drillpipe was changed to a lighter drillpipe to reduce the sideforces.
The new system resulted in a successful drilling and section TD was reached ahead of the estimated perfect time.
With this paper we provide a detailed example of how a casing wear issue was addressed. The drivers we extract from this case are useful for the planning of future operations, especially in extended-reach wells.
Transforming Waste Heat to Electric Power in Oil and Gas Compression Systems using Supercritical Carbon Dioxide
Authors: Soulas Thomas 
Published: November 2019

Abstract
In the oil and gas sector, energy is wasted far too often. By recovering those losses and increasing efficiency, the operators of production facilities and transmission systems can make dramatic improvements and yield new commercial opportunities. For instance, energy recovery may potentially allow profits to be realized from fields that might otherwise be marginal prospects or represent an additional revenue stream for gas pipeline transmission and distribution network operators.
Now, a breakthrough technology that supports energy recovery from heat rejected from a broad range of industrial processes is available to the oil and gas industry. There is a lot of wasted energy available. Globally, it is estimated that rejected heat corresponds to about 65% of the net energy input across the industrial infrastructure, with numbers varying from 60% to 70% depending on the region, including the Middle East.
Considerable waste heat is ejected from equipment like the gas turbines that are commonly used in mechanical drive applications found in the compression processes of gas production platforms and transmission pipelines. While most gas turbine heat recovery systems use a bottoming steam cycle to improve thermal efficiency, so-called combined cycle turbines, the new development presented in this paper is significantly different.
Intelligent Identification of Least-Connected Components of Reservoir Simulation Models
Authors: Rogowski Marcin , Kayum Suha 
Published: November 2019

Abstract
Reservoir simulation models that represent large-sized reservoirs require significant use of High-Performance Computing resources. Several solutions aim to reduce the load of an individual simulation such as upscaling to consequently reduce the number of grid cells of the model, splitting the model into independent sub-models using crop functionality, or dividing the model into sectors and running these sub-models independently. As it preserves the flux boundary condition, sector modeling could potentially result in the least erroneous solution, especially if the sectors are defined on the regions of least connectivity.
This paper aims to propose an automated, intelligent method to divide the reservoir model into an arbitrary number of least-connected smaller sectors. Streamline simulation output is used as a representation of reservoir connectivity. A graph is built using cells as graph vertices, and the edge weight is calculated based on the time of flight of oil and water between cell pairs.
By presenting the problem in this manner, a graph is built where the non-water cells have equal weight, and the stronger the connection between two cells, represented by the lower time of flight, the larger the edge weight. A graph partitioning tool is used to minimize the total weight of edges cut while keeping the number of vertices in each sub-graph balanced up to a specified tolerance. Partitioning of a graph specified this way is equivalent to splitting the reservoir model into sub-models while avoiding cutting of strongly connected parts, hence minimizing the boundary flux. Applying this method to sector modeling allows splitting a model into a number of smaller sub-models that can be used independently as the interactions between them are minimized, as demonstrated by minimizing flux between them.
The proposed novel method has been tested on several real-field as well as synthetic reservoir models. The method has resulted in sub-models of loosely connected reservoirs. The advantage of our proposed method is especially seen for strongly connected models where it is difficult to identify the least erroneous partitioning for sector generation manually. With the use of our method, it is guaranteed to automatically find the least connection, while minimizing the error that sector division produces, as evident by the low flux between the sector models.
Comparison of open liver resection and RFA for the treatment of solitary 3-5 cm hepatocellular carcinoma: a retrospective study
Authors: Lei Jianyong , Lunan Yan , Dajiang Li , Wentao Wang 
Published: November 2019

Abstract
Aim: The goal of this study was to compare the postoperative results of liver resection and radiofrequency ablation (RFA) for the treatment of small hepatocellular carcinoma (HCC) (3-5 cm). Patients and methods: We retrospectively collected 122 patients with small solitary HCC treated at our center from Jan 2011 to Dec 2015, with diameters in the range of 3-5 cm. According to the treatment program received at our center, they were divided into the liver resection group (72 patients) and the RFA group (50 patients). Result: In comparison with the RFA group, the resection group had a longer operative time, and greater intra-operative blood loss (P<0.01), more hepatic inflow occlusion , and longer postoperative hospital stay (P<0.01). The 1-, 3-, and 5-year expected overall survival rates and tumor-free survival rates were comparable between the two groups. Cox regression analysis showed that resection or RFA was not a significant risk factor for overall or tumor-free survival for HCC. Conclusions: For solitary HCC of 3-5 cm in diameter, RFA can achieve better in-hospital clinical results and similar long-term outcomes, and RFA can be considered for wide application, especially for central cases.
MicroRNA Expression Profiles Analysis in Sperm Reveals hsa-mir-191 is an Auspicious Omen of in Vitro Fertilization
Authors: Xu Hua , Wang Xin , Wang Zhikai , Li Jianhui , Xu Zhiming , Miao Maohua , Chen Guowu , Lei Xiangdong , Wu Jun , Shi Huijuan , Wang Ke , Zhang Tiancheng , Sun Xiaoxi 
Published: November 2019

Abstract
Background: MicroRNAs (miRNAs) are a class of noncoding small RNAs that play important roles in many physiological processes by regulating gene expression. Previous studies have shown that the expression levels of total miRNAs increase during mouse embryonic development, and some miRNAs control the regulatory network in development progression. However, few studies have focused on the effects of miRNAs on early human embryonic development. The relationship between miRNAs and early human embryogenesis is still unknown. Results: In this study, sperm samples from 102 patients with a normal sperm index but treated with assisted reproductive technology (ART) were collected for small RNA sequencing, and the relationships between differentially expressed small RNAs and the fertilization rate (FR), blastocyst rate and high-quality embryo rate (HQER) were analyzed. The sperm samples with high hsa-mir-191 expression had a higher FR, effective embryo rate (EER) and HQER. hsa-mir-191 was used as a single indicator to predict the HQER. The receiver operating characteristic (ROC) curve had an area under the ROC curve (AUC) of 0.686. We also found that hsa-mir-191 expression is correlated with an abnormal sperm rate (cor = 0.29, p< 0.01). We also evaluated the relationship between hsa-mir-34c and early human embryo development in these 102 sperm samples and obtained negative results. Conclusions: These findings suggest that high hsa-mir-191-5p expression in sperm is associated with early human embryonic quality and that hsa-mir-191-5p could be used as a potential marker to screen high-quality sperm to improve the success rates of in vitro fertilization (IVF). Keywords: miRNA, hsa-mir-191, hsa-mir-34c, RNA-Seq, Embryonic development
Association between the elevation of tumor-infiltrating lymphocytes in different subtypes of primary breast tumors and prognostic outcomes: A meta-analysis
Authors: He Lin , Wang Yaling , Wu Qian , Song Yuhua , Ma Xuezhen , Wang Haiji 
Published: November 2019

Abstract
Purpose To investigate the impact of the elevation of tumor-infiltrating lymphocytes (TILs) in different molecular subtypes of primary breast cancer, i.e. a 10% increment of TILs in tumor and lymphocyte-predominant breast cancer (LPBC), on long-term survival and pathological complete response (pCR) and to compare the presentation of high-level TILs across these molecular subtypes.Methods Citation retrieval was performed in the PubMed, Cochrane Library, Embase and Web of Science databases. All statistical calculations were performed by the software of StataSE version 12.0.Results Twenty-two eligible clinical trials including 15676 unique patients were included for meta-analysis. The 10% increment of TILs in human epidermal growth factor receptor 2 (HER2)-overexpression (pooled Hazard ratio (HR), 0.92; 95% CI, 0.89-0.95) and triple-negative (TN) (pooled HR, 0.90; 95% CI, 0.89-0.92) breast tumors significantly improved overall survival (OS) but in Luminal tumor subtype was inert to improve that (pooled HR, 1.06; 95% CI, 0.99-1.13). It was also associated with an increased pCR rate in breast cancers (pooled Odds ratio (OR), 1.27; 95% CI, 1.19-13.5). LPBC was significantly related with a higher pCR rate (OR, 2.73; 95% CI, 2.40-3.01) than non-LPBC. This significant difference was also shown in different molecular subtypes of LPBC compared with those of non-LPBC. HER2-amplified (OR, 3.14; 95% CI, 1.95-5.06) and TN (OR, 4.09; 95% CI, 2.71-6.19) phenotypes of breast cancers expressed significantly elevated high-level TILs than Luminal tumor subtype, although the presentation of those between the former two subsets was not significantly different (OR, 1.30; 95%CI, 0.83-2.04).Conclusion The elevation of TILs in breast tumors predicts promising prognostic outcomes, particularly in the HER2-overexpression and TN subtypes. These benefits in Luminal tumor subtype need to be warranted.
Understanding the meaning of conformity to feminine norms in lifestyle habits and health: A cluster analysis.
Authors: Esteban-Gonzalo Sara , Ho Petula Sik Ying , Aparicio-García Marta Evelia , Esteban-Gonzalo Laura 
Published: November 2019

Abstract

Background: Gender roles impact different spheres of life and lead women to behavioral patterns and lifestyle habits associated with femininity, generating important differences between men and women in health. The present study analyzed relationships between conformity to the feminine norms and different lifestyle indicators: educational level, marital status, alcohol consumption, tobacco consumption, sleeping hours, social support and physical activity. Additionally, cluster analysis was developed in order to identify different patterns of gender role conformity. Methods: The sample was made up of 347 women age 18-70 from Spain. Data collection was conducted during 2014. Results: Multiple logistic regression analyses produced odds ratios showing that women with lower feminine role conformity were more likely to use tobacco and alcohol, but less likely to share their lives with someone. Cluster analysis found four different profiles of gender role conformity, related to different patterns of alcohol consumption and marital status. Conclusions: Conformity to feminine norms was associated with basic affective conditions such as sharing life with others and with alcohol and tobacco consumption, but not with physical activity, social support and sleep duration. While tobacco and alcohol use has important health implications, public health systems should pay attention to gender related variables in order to design and implement specific prevention programs.
Estimating Optimal Dynamic Treatment Strategies Under Resource Constraints Using Dynamic Marginal Structural Models
Authors: Caniglia Ellen , Murray Eleanor , Hernan Miguel , Shahn Zach 
Published: November 2019

Abstract
Background: Existing methods for estimating the optimal treatment or monitoring strategy typically assume unlimited access to resources. However, when a health system has resource constraints, such as limited funds, access to medication, or monitoring capabilities, medical decisions must balance impacts on both individual and population health outcomes. That is, decisions should account for competition between individuals in resource usage. A simple solution is to estimate the (counterfactual) resource usage under the possible interventions and choose the optimal strategy for which resource usage is within acceptable limits. Methods: We propose a method to identify the optimal dynamic intervention strategy that leads to the best expected health outcome accounting for a health system's resource constraints. We then apply this method to determine the optimal dynamic monitoring strategy for people living with HIV when resource limits on monitoring exist using observational data from the HIV-CAUSAL Collaboration. In our example, we identify the optimal CD4 cell count at which to decrease monitoring frequency from every 3-6 months to every 9-12 months among the subset of strategies that satisfy a hypothetical constraint on monitoring. We find the resource constrained dynamic strategy (RCDS) that minimizes the risk of virologic failure given a hypothetical resource constraint where individuals can only be monitored on average every 6 months. Results: Given the hypothetical resource constraint, the optimal monitoring strategy is `monitor CD4 cell count and HIV-RNA every 3-6 months when CD4 is below 320 cells/ml and every 9-12 months when CD4 is above 320 cells/ml.' Conclusions: We describe and and apply a method to identify the optimal RCDS given a hypothetical resource constraint. Similar applications may be useful in settings with limited availability of or capacity for monitoring individuals living with HIV or other chronic diseases.
Height predict incident non-alcoholic fatty liver disease in a general adult population, independent of body mass index and metabolic syndrome
Authors: Kumari Shubham , Wang Xuena , Gu Yeqing , Huang Yuhan , Zhang Qing , Liu Li , Meng Ge , Wu Hongmei , Sun Shaomei , Wang Xing , Zhou Ming , Jia Qiyu , Wang Guolin , Song Kun , Niu Kaijun 
Published: November 2019

Abstract
Background Early-life hormonal and nutritional factors can greatly influence the risk of non-alcoholic fatty liver disease (NAFLD). Adult height is a simple marker for these factors. We aimed to evaluate adult height as a predictor of NAFLD.Methods We performed a prospective cohort study of 35, 994 participants recruited from 2010 to 2016 in Tianjin, China. NAFLD was diagnosed by ultrasound. Adjusted Cox proportional hazards regression models were conducted in 2019 to assess the gender-specific association between the quintiles of height and the incidence of NAFLD.Results Participants were followed up for 5.5 years with a mean follow-up of 2.6 years. During the follow-up period, 6,245 of 35,994 participants developed NAFLD. The multiple-adjusted hazard ratios (95% confidence interval) of NAFLD for increasing quintiles of height were 1.00 (reference), 0.90 (0.81, 0.99), 0.97 (0.87, 1.07), 0.86 (0.78, 0.96), and 0.84 (0.75, 0.94) ( P for trend < 0.01) in males and 1.00 (reference), 0.97 (0.86, 1.09), 0.98 (0.86, 1.11), 0.93 (0.81, 1.06), and 0.84 (0.73, 0.96) ( P for trend = 0.02) in females, respectively.Conclusions The study is the first to demonstrate adult height is a new, simple and inexpensive marker for ultra-early prediction of NAFLD.