bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Advances in Downhole Fiber Optics Modeling & Analytics: Case Studies
Authors: Bale Derek S , Satti Rajani P , Failla Roberto , Harper Jason , Raggio John 
Published: November 2020

Abstract
In recent years, the upstream oil and gas industry has witnessed significant breakthroughs in developing and deploying permanent, on-demand, and distributed temperature (DTS) and acoustic (DAS) fiber-optic monitoring systems to optimize well completions and enhance production. Beyond steady advances in hardware, challenges associated with the analysis of distributed optical data are being addressed to enable delivery of value-driven answer solutions and services. Such solutions are often nontrivial and must be driven by scientific workflows in which data-driven models, advanced analytics and most importantly, physics-based models are applied at the right scale to correlate the data to downhole events.
In this study, we present a methodology for integrating state-of-the-art intelligent completion and production tools together with a robust modeling and analytics framework for the efficient development of data interpretation services for complex downhole environments. The answer product platform discussed is built on fast computational models, robust data-driven analytics, cloud-based data streaming and management services, and real-time reporting delivery systems. Several case-studies demonstrate how our fiber-optics solutions and analysis are leveraged for applications such as leak detection, fluid injection profiling, acid placement, sand detection, and water ingress. For each case-history, we discuss the operational workflow for the downhole intelligent assembly, procedures for acquiring high-resolution DTS/DAS data, and the use of advanced fast physics or data driven models used to deliver the solution. Some of the application examples (e.g. water ingress and sand detection) also demonstrate how simultaneous measurements of DTS and DAS data are often critical to detecting and devising a strategy for mitigating well-specific issues.
The case-studies presented in this study demonstrate how vast amounts of data can be acquired by fiber-optic interrogation systems and subsequently interpreted in real-time, or near real-time. Such a process is enabling oil and gas operators to make data-driven decisions that drive optimized reservoir performance and proactively mitigate operational risk such as NPT due to equipment failure.
Revolutionary Products and Materials from Heavy Oil that Producers, Investors, Consumers and Regulators Should Know About
Authors: Elias Ramon , Medizade Mason M. , Zhang Shanju , Elias Stephen R. 
Published: November 2020

Abstract
New technology and energy production have been fundamental staples for improving our quality of life, creating jobs and expanding a vibrant U.S. and global economy. Fossil resources like crude oil and natural gas have been essential for accomplishing this. Main uses have been to fuel the production of electricity, generate heat for our comfort and manufacturing, and supply energy for transportation. Petroleum and natural gas also produce many important precursors for a multitude of products and materials that also have transformed our world. Lesser known is that our need for these materials is growing faster than our need for fuel.
An emerging demand for precursors used to produce carbon-based substances like carbon fiber, carbon nanotubes and graphene is one reason why. These materials are composed entirely of carbon. Resources containing high amounts of carbon are needed for their production. Crude oil and natural gas are well suited for that purpose and we show that a new era of uses for these important resources is evolving.
Why the interest in carbon-based materials? They are very strong, very light, and have a wide range of uncommon and extraordinary physical properties. The synthesis of these materials is rapidly gaining importance as one of the most exciting and promising innovations ever developed by man. While various sources for producing carbon-based materials have been identified, petroleum or crude oil is proving to be both suitable and preferred.
In this review paper, we (i) give examples of the numerous incredible new carbon-based products and materials that are advancing and growing, (ii) briefly discuss known processes used to make the needed material precursors from petroleum, (iii) show evidence that refinery yields are shifting from fuels to materials, and (iv) cite exciting and forward looking research programs now underway. Also discussed is why lower API gravity, or higher density petroleum known as heavy oil, could be a preferred source of carbon-based material precursors. The discussion that follows gives ample reason to step back and reassess the views expressed by some on the continued importance of fossil resources and their emerging new uses in today's world.
Synergistic Surfactant Blends for Wettability Alteration in Wolfcamp and Eagle Ford Shale for Improved Oil Recovery
Authors: Singh Robin , Miller Joseph 
Published: November 2020

Abstract
The goal of this work is to develop synergistic surfactant blends that can perform wettability alteration for improved oil recovery (IOR) in tight liquid-rich unconventional shale reservoirs. Shales samples from Eagle Ford and Wolfcamp formation were used in this study. The performance of these surfactant systems in altering the wettability and improving the spontaneous imbibition process was evaluated. Comprehensive screening of surfactants (anionic, non-ionic, zwitterionic) was performed in this study. First, aqueous stability tests of these surfactant systems were performed at reservoir temperature. Second, contact angle experiments were conducted on polished oil-wet shale (Eagle Ford and Wolfcamp) chips to screen formulations with optimal wettability-altering capabilities. Third, bulk emulsion stability was investigated by measuring the half-lives of the emulsions. Fourth, the interfacial tensions between oil-surfactant formulations were measured via the pendant drop method using a goniometer. Finally, spontaneous imbibition experiments in tight cores such as carbonates and shale were performed to evaluate the efficacy of these formulations in recovering oil.
Several anionic surfactants and their blends with anionic, non-ionic, and zwitterionic cosurfactants were shortlisted based on the aqueous stability tests. Polished shale chips from Eagle Ford and Wolfcamp formation were made oil-wet by aging them with crude oil at 85 °C for 30 days. Contact angle experiments revealed that these synergistic surfactant blends can alter the wettability from oil-wet to water-wet conditions and outperform the performance of the individual surfactant system. The spontaneous imbibition experiments demonstrate that a significant amount of oil (11.8 to 52 % OOIP) can be recovered from tight carbonate rocks by optimally selecting surfactant formulations. It was shown that surfactant imbibition in an originally oil-wet shale sample can recover a significant amount of oil (12.96 to 22.4% OOIP). Unconventional liquid-rich shale plays such as Eagle Ford, Bakken and Wolfcamp constitute a major portion of the oil production in the US. Surfactants can significantly improve production from such shales and improve oil recovery. This study offers a novel systematic investigation of synergistic surfactant blends which alters the wettability of oil-wet shale to water-wet and induce spontaneous imbibition in liquid-rich shales to increase oil recovery.
Dynamic Simulation of Electrical Submersible Pump ESP Applied to Producing Wells in Unconventional Reservoirs
Authors: Nemoto Rafael H. , Hackworth Matthew R. , Pereyra Eduardo , Sarica Cem 
Published: November 2020

AbstractElectrical Submersible Pumps (ESPs) are commonly applied to producing wells in unconventional reservoirs. Typically, the operator places the ESP in the vertical section to minimize installation risks; however, some operators have reported installing ESPs in the lateral section to improve operation and production. This paper will present a study of the interaction between reservoir inflow, wellbore geometry, and ESP operation using a commercial dynamic multiphase flow simulator (OLGA). The study will further quantify the benefits and disadvantages of deploying the ESP in the vertical and lateral sections of a horizontal well. The investigation uses operations data from a Permian basin well, with an ESP operating in the vertical section of a horizontal well. The dynamic simulation model was built and tuned to match the field data with two different production stages: early and late production. Hypothetical cases with the ESP located in the lateral section and with different well geometries (toe-up and toe-down) are also investigated. For the performance evaluation of different ESP deployment positions, the following indicators were considered: (a) production flow rate, (b) likelihood of pressure surging occurrence, and (c) flow pattern and gas volume fraction reaching the ESP system. Finally, the study provides guidelines on the ESP deployment location for improved operation and production.
Hydraulic-Fracture-Width Inversion Using Low-Frequency Distributed-Acoustic-Sensing Strain Data—Part I: Algorithm and Sensitivity Analysis
Authors: Liu Yongzan , Jin Ge , Wu Kan , Moridis George 
Published: November 2020

Summary
Low-frequency distributed-acoustic-sensing (LF-DAS) data, which can be treated as linear-scaled strain variations, have been used recently to monitor hydraulic-fracturing treatments. Forward geomechanical modeling has been the subject of recent research efforts to better interpret the observed signatures of field LF-DAS data. To the best of our knowledge, there is no study that attempts to quantitatively characterize fracture geometries by directly inverting the LF-DAS strain data. In this study, we propose an inversion algorithm, in which the strains monitored by LF-DAS along an offset well are related to the fracture widths through a Green function. A 3D displacement-discontinuity method is used to construct the Green function. The least-squares method is first used to solve the linear system of equations. Regularization might be needed to stabilize the underdetermined system. Then, Markov-chain Monte Carlo (MCMC) simulations are conducted to generate fracture-width samples from the target distribution of LF-DAS strain data and to quantify uncertainties associated with the inverted widths.
The inversion results obtained by the least-squares method are nonunique, heavily depending on the a priori regularization information. Regardless of the additional constraints imposed on the linear system, the inverted fracture width at the monitor-well location is always consistent with the true value because the LF-DAS data show a dominant sensitivity of fracture width near the monitor well. MCMC simulation results confirm that the LF-DAS strain data can only impose constraints on fracture segments near the monitor well. Moreover, the average value of the inverted widths in the vicinity of the monitor well is usually the same as the width right at the monitor well, except for the very early time after fracture hit when there are sharp width variations near the fracture tip. Therefore, it is efficient to use a single width for each fracture during the inversion process. The presented algorithm is successfully applied to invert the width evolution near the monitor well as a function of injection time.
The results of this study demonstrate how much information can be obtained with high confidence from the inversion of LF-DAS strain data, which is beneficial for future use of LF-DAS data. The accurate estimation of fracture width at the monitor well can be used to calibrate hydraulic-fracturing models, improve the design of completion parameters such as proppant size, and provide the possibility of characterizing the whole fracture geometry with additional information or assumptions.
Understanding the Plugging Performance of HPAM-Cr (III) Polymer Gel for CO2 Conformance Control
Authors: Sun Xindi , Bai Baojun , Alhuraishawy Ali Khayoon , Zhu Daoyi 
Published: November 2020

SummaryWith the demand for conformance control in carbon dioxide (CO2) flooding fields, hydrolyzed polyacrylamide-chromium [HPAM-Cr (III)] polymer gel has been applied in fields for CO2 conformance control. However, the field application results are mixed with success and failure. This paper is intended to understand the HPAM-Cr (III) polymer gel plugging performance in CO2 flooding reservoirs through laboratory experiments and numerical analysis. We conducted core flooding tests to understand how the cycles of CO2 and water affect the HPAM-Cr (III) polymer gel plugging efficiency to CO2 and water during a water-alternating-gas (WAG) process. Berea Sandstone cores with the permeability range of 107 to 1225 md were used to evaluate the plugging performance in terms of residual resistance factor and breakthrough pressure, which is the minimum pressure required for CO2 to enter the gel-treated cores. We compared the pressure gradient from the near-wellbore to far-field with the gel breakthrough pressure, from which we analyzed under which conditions the gel treatment could be more successful. Results show that HPAM-Cr (III) polymer gel has higher breakthrough pressure in the low-permeability cores. The polymer gel can reduce the permeability to water much more than that to CO2. The disproportionate permeability reduction performance was more prominent in low-permeability cores than in high-permeability cores. The gel resistance to both CO2 and brine significantly decreased in later cycles. In high-permeability cores, the gel resistance to CO2 became negligible only after two cycles of water and CO2 injection. Because of the significant reduction of pressure gradient from near-wellbore to far-field in a radial flow condition and the dependence of breakthrough pressure on permeability and polymer concentration, we examined hypothetical reservoirs with no fractures, in which impermeable barriers separated high- and low-permeability zones and in which the gel was only placed in the high-permeability zone. We considered two scenarios: CO2 breaking through the gel and no CO2 breakthrough. No breakthrough represents the best condition in which the gel has no direct contact and can be stable in reservoirs for long. In contrast, the breakthrough scenario will result in the gel's significant degradation and dehydration resulting from CO2 flowing through the gel, which will cause the gel treatment to fail.
The distribution of refraction by age and gender in a non-myopic Chinese children population aged 6-12 years
Authors: Zhang Xiyan , Zhou Yonglin , Yang Jie , Wang Yan , Yang Wenyi , Gao Liuwei , Xiang Yao , Zhang Fengyun 
Published: November 2020

Abstract
Background: The Prevalence of myopia is increasing in China. This study aimed to explore the distribution of spherical equivalent (SE) and its association with age, body mass index (BMI), gender in a non-myopic Chinese children population aged 6 to 12 years. Methods: A total of 6362 students were recruited for ophthalmological investigation. Demographic and myopia related behavioral information was collected. SE value was measured by the Topcon RM-8900 or KR-800autorefractors. Potential independent risk factors were determined with Odds Ratio (OR) and 95% Confidence Interval (CI) by logistic regression analysis. We further constructed the nomogram model to predict future onset of myopia.Results: Among the study population, 3900 (61.3%) were non-myopic. The prevalence of myopia is 38.0% for boys and 39.5% for girls. The average SE values were 0.50±0.70 D for boys and 0.60±0.80 D for girls. The mean SE values decreased with age, and the value of height and BMI took on a stable trend. Threshold values for myopia varied across age groups and gender. Paternal myopia (OR: 1.22, 95%CI: 1.01-1.48), near-work activities on weekends (2.56, 1.17-5.61), and outdoor activities (0.68, 0.54-0.86) were associated with potential myopic in students. Conclusion: A series of age-gender based SE threshold values were established to predict myopia in Chinese children aged 6 to 12 years. High risk factors for myopia included paternal myopia, near-work activities on weekends, and outdoor activities. Countermeasures are encouraged to reverse the increasing trend of myopia in children.
There is no Dose-response Relationship between Allogeneic Blood Transfusion and Healthcare-associated Infection: A Retrospective Cohort Study
Authors: Lv Yu , Xiang Qian , Lin Jia , Jin Ying Zong , Fang Ying , Cai Hong M , Wei Qiong D , Wang Hui , Wang Chen , Chen Jing , Ye Jian , Xie Caixia , Li Ting L , Wu Yu J 
Published: November 2020

Abstract
BackgroundThe association between allogeneic blood transfusion (ABT) and healthcare-associated infection (HAI) is considered dose-dependent. However, this association may be confounded by transfusion duration, as prolonged hospitalization stay increases the risk of HAI. Also, it is not clear whether specific blood products have different dose-response risks.MethodsIn this retrospective cohort study, a logistic regression was used to identify confounding factors, and the association between specific blood products and HAI were analyzed. Then Cox regression and restricted cubic spline regression was used to visualize the hazard of HAI per transfusion product.ResultsOf 215338 inpatients observed, 4.16% were transfused with a single component blood product. With regard to these transfused patients, 480 patients (5.36 %) developed a HAI during their hospitalization stay. Logistic regression showed that red blood cells (RBCs) transfusion, platelets transfusion and fresh-frozen plasmas (FFPs) transfusion were risk factors for HAI [odds ratio (OR) 1.893, 95% confidence interval (CI) 1.656–2.163; OR 8.903, 95% CI 6.646–11.926 and OR 1.494, 95% CI 1.146–1.949, respectively]. However, restricted cubic spline regression analysis showed that there was no statistically dose-response relationship between different transfusion products and the onset of HAI.ConclusionsRBCs transfusion, platelets transfusion and FFPs transfusion were associated with HAI, but there was no dose-response relationship between them.
Proteasome&nbsp;Inhibitors&nbsp;Reduce&nbsp;Thrombospondin-1&nbsp;Release&nbsp;in&nbsp;Human&nbsp;Dysferlin-Deficient&nbsp;Myotubes
Authors: Fernández-Simón Esther , Lleixà Cinta , Suarez-Calvet Xavier , Diaz-Manera Jordi , Illa Isabel , Gallardo Eduard , de Luna Noemí 
Published: November 2020

Abstract
Background Dysferlinopathies are a group of muscle disorders causing muscle weakness and absence or low levels of dysferlin, a type-II transmembrane protein and the causative gene of these dystrophies. Dysferlin is implicated in vesicle fusion, trafficking, and membrane repair. Muscle biopsy of patients with dysferlinopathy is characterized by the presence of inflammatory infiltrates. Studies in the muscle of both human and mouse models of dysferlinopathy suggest dysferlin deficient muscle plays a role in this inflammation by releasing thrombospondin-1. It has also been reported that vitamin D3 treatment enhances dysferlin expression. The ubiquitin-proteasome system recognizes and removes proteins that fail to fold or assemble properly and previous studies suggest that its inhibition could have a therapeutic effect in muscle dystrophies. Here we assessed whether inhibition of the ubiquitin proteasome system prevented degradation of dysferlin in immortalized myoblasts from a patients with two missense mutations in exon 44. MethodsTo assess proteasome inhibition we treated dysferlin deficient myotubes with EB1089, a vitamin D3 analog, oprozomib and ixazomib. Western blot was performed to analyze the effect of these treatments on the recovery of dysferlin and myogenin expression. TSP-1 was quantified using the enzyme-linked immunosorbent assay to analyze the effect of these drugs on its release. A membrane repair assay was designed to assess the ability of treated myotubes to recover after membrane injury and fusion index was also measured with the different treatments. Data were analyzed using a one-way ANOVA test followed by Tukey post hoc test and analysis of variance. A p≤0.05 was considered statistically significant. Results Treatment with proteasome inhibitors and EB1089 resulted in a trend towards an increase in dysferlin and myogenin expression. Furthermore, EB1089 and proteasome inhibitors reduced the release of TSP-1 in myotubes. However, no effect was observed on the repair of muscle membrane after injury. ConclusionsOur findings indicate that the ubiquitin-proteasome system might not be the main mechanism of mutant dysferlin degradation. However, its inhibition could help to improve muscle inflammation by reducing TSP-1 release.
Impact of COVID-19 on selected criminal activities in Dhaka, Bangladesh
Authors: Rashid Sungida 
Published: November 2020

Abstract
The COVID-19 pandemic has made a substantial impact on the historical criminal trend of the world. Using Dhaka Metropolitan Police (DMP) recorded open crime data of the total number of arrests, this article aims to understand how the frequency of selected crime trends has changed during the pandemic in Dhaka city, the capital of Bangladesh. Time-series forecasting models ARIMA (Auto Regressive Moving Average Model) are used to forecast the expected frequency of arrests in different crime types in 2020 in the absence of the pandemic. Forecasting techniques are applied to estimate six-month-ahead forecasts of the total number of arrests of arms dealing, vehicle theft, and illegal drug trafficking. The actual and predicted numbers of total arrests for vehicle thefts are decreased during pandemic while actual arrests in illegal drug trafficking show a steep upward trend- around 75% more than that of the expected frequencies. Estimated results are used to recognize scopes and suggestions for future research on the relationship between crimes and pandemic.