bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancement of Current Methodologies Used for Tubular Connection Product Line Validation
Authors: Xie Jueren , Xie Junfeng 
Published: November 2019

Abstract
For high pressure/high temperature (HPHT) and thermal wells, it is important to verify that the selected tubular connection product possesses adequate structural integrity and sealing capacity under the demanding load conditions typically experienced by these wells throughout their life cycle.
Individual premium connection designs are typically evaluated and qualified to broadly adopted industry standards, such as ISO 13679 (2019) and API RP 5C5 (2017) for HPHT wells up to temperatures of 180°C, and ISO 12835 (2013) for thermal wells that experience temperatures from 180°C to 350°C. Proprietary operator-defined protocols are also used by some operators for connection qualification. While the current standards recognize that it is neither necessary nor practical for manufacturers to complete full-scale physical testing of the connection design for every different tubular diameter, weight and grade as a means to achieve full product line validation, the development of a practical framework and effective guidelines to achieve this outcome continues to be a work in progress. The basic approach allows interpolation and extrapolation of the results established through combined testing and analysis programs completed on a selected subset of sizes and weights of the full product line of the connection design.
This paper starts with a review of current standards for qualifying tubular connections for HPHT and thermal wells. It presents guidelines and an approach to facilitate the performance evaluation and product line validation of connection designs based on the use of Finite Element Analysis (FEA) methods and the recently established sealability criterion. To illustrate the approach, parametric FEA case studies were completed to determine the impact of different tubular sizes and weights on the sealability performance of gas-tight tubing and casing connections under HPHT and thermal well loading conditions. Based on the analysis results, recommendations and considerations for on-going research are made to improve the confidence in the use of interpolation and extrapolation methods presented in the current standards when conducting tubular connection product line validation exercises.
Corrosion Failure and Control of Carbon Steel and Anti-Corrosion Performance Evaluation of Candidate Materials in Thermal Applications
Authors: Li Jiankuan , Sun Chong , Roostaei Morteza , Mahmoudi Mahdi , Fattahpour Vahidoddin , Zeng Hongbo , Luo Jing-Li 
Published: November 2019

Abstract
This study presents an investigation of the on-site corrosion of carbon steel pipes with stainless steel mesh screens in a steam flood well in the Athabasca oil sand reservoirs to determine the failure patterns and mechanisms. To mitigate the corrosion of carbon steel, several candidate materials were selected, and their corrosion resistance was investigated.
In this work, the corrosion behavior and film characteristics of carbon steel pipes were studied by surface analysis techniques such as scanning electron microscopy, energy dispersive spetrocsopy and X-ray diffraction. Corrosion resistant alloys (proRSf and proRSc), anti-corrosion coating (proRA05a) and pre-treated steel (proRAQa) were considered as alternative materials to carbon steel (proRAa and proRAb) and their corrosion protection performance in brine solution was evaluated by electrochemical methods such as potentiodynamic sweep and electrochemical impedance spectroscopy.
Results show that severe erosion-corrosion occurred on inner wall of the pipes and caused significant wall-thinning of pipes along with localized corrosion damages, which is the dominant reason for base pipe failure. In spite of the slight corrosion on outer wall of the base pipe, severe localized corrosion appeared at the interface between the carbon steel pipe and stainless steel mesh screens due to the galvanic corrosion effect of dissimilar metals. The corrosion rates of the corrosion-resistant materials were two or three orders of magnitude lower than that of carbon steel. The corrosion resistance ranking order is proRSc &gt; proRSf &gt; proRA05a &gt; proRAQa &gt; proRAa &gt; proRAb.
This study improves the material selection procedure in thermal operations by investigating several alternatives to carbon steel. It also provides a testing procedure to assess the corrosion resistance of the material in thermal applications.
An Overview of the Field Performance of Tubing Deployed Flow Control Devices in the Surmont SAGD Project
Authors: Nespor Kristian , Chacin Jesus , Ortiz Julian , Morter Julie , Romanova Uliana , Bilic Jeromin , Gohari Kousha , Becerra Oscar 
Published: November 2019

Abstract
Flow Control Devices (FCDs) are known to enhance efficiency of oil production, overall project economics and environmental performance that is currently of particular importance for Steam Assisted Gravity Drainage (SAGD) operators in Western Canada. FCDs have been utilized in SAGD wells over a decade, primarily, as liner deployed (LD) applications. Compared to LD FCDs, tubing deployed (TD) FCDs for SAGD producers are less common and require better understanding from the standpoint of completion design and operational strategy.
A study has been conducted on TD FCD installations in producer wells in the Surmont SAGD project. The study was aimed to understand failure modes and causes for several failed SAGD producers retrofitted with TD FCDs. Due considerations were given to key factors such as geology, runtime, operational practices and the possibility of failure of the slotted liner. Caliper log, fiber optics and downhole imaging data were used in the study. FCD strings pulled from the ground have been also analyzed.
All failures were found to be erosive wear with localized full wall loss of the TD FCD base pipe. No detectable erosion or other damage to FCDs are observed. As a general practice, a less aggressive operation strategy for wells with TD FCD compared to wells with LD FCDs was implemented after the study to avoid new failures. Proper screen sizing for TD FCD retrofits in slotted liner wells was identified as an important factor to provide effective sand control and may help reduce failures, but screen sizing was found not to have a direct effect on the failures investigated. The study shows that TD FCD retrofits have proven to be successful; however, special considerations are required when designing TD FCDs installations for SAGD producers, compared to LD FCDs, in order to reduce risk of erosive damage and failure.
Foam Formulation for High Temperature SAGD Applications
Authors: Adetunji Lukemon A. , Ben-Zvi Amos , Filstein Alex 
Published: November 2019

Abstract
In SAGD operations, the steam chamber temperature can be as high as 250°C. Foam formulations that can withstand such high temperature are required for field deployment of foam as conformance control technique.
An evaluation of 12 surfactant formulations for their viability as steam foam candidate at chamber temperatures as high as 250°C is presented. Unlike other studies in the literature that used nitrogen for foam generation, methane was employed in this project.
This project reveals that strong foam can be formed at 250°C. Also, foam is only generated within a specific range of methane mass quality. Stronger foam was formed when steam and methane were injected simultaneously into the core. Lastly, the existence of residual oil in the core reduced the foam strength.
We analyzed the effect of a few parameters on foam strength. Parameters considered include concentration of surfactant, presence of steam as well as methane, mass quality of methane, and residual oil saturation.
Laboratory analyses comprising thermal stability, solubility, foam height, adsorption, and coreflood, were conducted.
The learnings from this project has the ability to accelerate the application of foam systems in high-temperature SAGD operations to increase conformance, maximize steam usage, and ultimately lead to overall reduction in GHG emissions from SAGD projects.
Lifetime Tubular Design: Combining Effects of Corrosion and Mechanical Wear
Authors: Liu Zhengchun , Samuel Robello , Gonzales Adolfo , Kang Yongfeng 
Published: November 2019

Abstract
During the lifetime of an oil/gas well, wellbore tubular structure might be subject to combined damage caused by both corrosion and mechanical wear. Therefore, it is necessary to conduct detailed stress analyses including these factors at the stage of tubular design.
An integrated well construction workflow was established for life-time well design. The temperatures and casing/tubing loads were obtained through numerical simulations of operations such drilling, stimulation, and production. All these simulations were accomplished using commercial software tools, including a thermal flow simulator and stress analyzer. On one hand, a commercial casing-wear simulator was used to predict the cumulative wear amount. On the other hand, a corrosion simulator was employed to predict pipe metal losses during each operation. The total amount of corrosion loss and mechanical loss were then compared against the maximum allowable wear for a safety check of the design.
The corrosion simulator was implemented in a computer program and integrated with the aforementioned commercial software of thermal flow and stress analysis. In a plot of maximum allowable wear versus depth, the curves of predicted wear, predicted corrosion, and predicted total metal loss are superimposed with the maximum allowable wear. This plot gives a straightforward and clear picture of the overall lifetime safety of the design.
A field case was studied with those integrated simulations. The production casing internal wear and internal/external corrosion were simulated. The predicted wear and corrosion data were in good agreement with the measured results. Further predictions provide rationales for future maintenance/workover operations.
Corrosion simulation and casing wear simulation were coupled with wellbore thermal flow analysis and stress analyses, helping proactively prevent tubular failure during the lifetime of the well. It is therefore valuable to include the integrated workflow during the wellbore tubular design where both corrosion and wear are involved.
Is radiographic lumbar spondylolisthesis associated with occupational exposures? Findings from a nested case control study within the wakayama spine study
Authors: Ishimoto Yuyu , Cooper Cyrus , Ntani Georgia , Yamada Hiroshi , Hashizume Hiroshi , Nagata Keiji , Muraki Shigeyuki , Tanaka Sakae , Yoshida Munehito , Yoshimura Noriko , Walker-Bone Karen 
Published: November 2019

Abstract
Abstract
Background: To explore the relationship between radiographic spondylolisthesis and occupational factors in a case-control study nested within the Wakayama Spine Study (WSS).
Methods: The WSS is a cross-sectional observational study amongst Japanese adults. All participants completed a lifetime occupational history and underwent X-rays of the lumbar spine (L1-S1) according to a pre-defined protocol. One trained surgeon graded the presence of a spondylolisthesis based upon ≥5% anterior or posterior slip at one or more levels. Cases, with lumbar spondylolisthesis, were compared with controls without, for their principal occupation and occupational exposures.
Results: In total, data were available for 722 adults (245 men and 477 women), mean age 70.1 (range 53-93) years. According to the pre-defined radiographic criteria, 117 were defined with spondylolisthesis (cases), leaving 605 controls. Cases were not significantly different from controls for age, gender, BMI, smoking or alcohol intake. However, cases were more than twice as likely to report occupational driving ≥ 4 hours/day (OR 2.39, 95% CI 1.08-5.27) after adjustment for age, gender and BMI. Additionally, after stratification by age using 75 years as a cut-point, cases were more than 3-fold more likely to report having worked in the agricultural/ fishing industries (OR 3.47, 95% CI 1.29-9.29) among those aged <75 years. A reduced risk of being a case was associated with climbing slopes/steps and walking.
Conclusions: A history of occupational driving and working in the agricultural/fishing industry were associated with radiographic spondylolisthesis in this cross-sectional population study. This finding requires further evaluation in longitudinal studies.
External fixation-assisted reduction for the treatment of neglected hip dislocations with limb length discrepancy: a retrospective study of 13 cases.
Authors: Li Pengyu , Song Wenhao , Dong Jinlei , Qiu Daodi , Zhou Dongsheng 
Published: November 2019

Abstract
Background: The purpose of this study was to evaluate a new method for treating neglected hip dislocation with limb length discrepancy by using external fixation-assisted pre-reduction. Methods: Thirteen patients admitted between January 2010 to February 2018 with a mean duration from injury to surgery of 5.0±2.1 months and an average preoperative leg-length discrepancy of 7.7±2.3 cm were enrolled in this study. The dislocation and associated acetabular fracture type, clinical outcomes and residual limb equality were evaluated. Results: All patients had posterior dislocations, and nine patients presented with acetabular fractures and were followed-up for at least 12 months. The average traction duration of external fixators was 28.8±8.0 days and all patients received second-stage open reduction and internal fixation. Six patients showed residual limb length discrepancy within 2 cm. Patients showed significant improvement in hip function and pain relief. Complications including avascular femoral head necrosis and osteoarthritis occurred in three patients. Conclusion: Effective correction of limb length discrepancy and improved function were observed in patients with neglected hip dislocations and limb equality using traction by external fixation combined with second-stage open reduction. Further follow-up is required to determine long-term outcomes. Keywords: neglected hip dislocation, limb length discrepancy, external fixatio
Comparison between minimally invasive plate osteosynthesis and open reduction–internal fixation for proximal humeral fractures: a meta-analysis based on 1050 individuals
Authors: Li Feilong , Nie Tao , Liu Xuqiang , Wang Fuqiang , Gu Zhiping , Tao Qianyuan , Yao Cong , Luo Xuwen 
Published: November 2019

Abstract
Background This meta-analysis aimed to compare the clinical outcomes and complications of minimally invasive plate osteosynthesis (MIPO) and open reduction–internal fixation (ORIF) in patients with proximal humeral fractures. Methods We searched PubMed, EMBASE, Ovid, and the Cochrane Library to identify all relevant studies from inception to April 2019. Cochrane Collaboration’s Review Manage 5.3 was used for meta-analysis. Results Sixteen studies involving 1050 patients (464 patients in the MIPO group and 586 patients in the ORIF group) were finally included. According to the meta-analysis, MIPO was superior to ORIF in operation time, blood loss, postoperative pain, fracture union time, and constant score. However, MIPO was associated with more exposure to radiation and axillary nerve injury. No significant differences were found in length of hospital stays and complication except for axillary nerve injury. Conclusion The present evidence indicates that compared to ORIF, MIPO had advantages in functional outcomes, operation time, blood loss, postoperative pain, and fracture union time for the treatment of PHFs. However, the MIPO technique had a higher rate of axillary nerve injury and longer radiation time compared to ORIF.
Serum Erythropoietin Concentration And Its Correlation With Stage Of Diabetic Retinopathy
Authors: Davidović Sofija , Nikola Babić , Sandra Jovanović , Sava Barišić , Desanka Grković , Aleksandar Miljković 
Published: November 2019

Abstract
Erythropoietin (EPO) is one of the systemic angiogenic factors, and its role in ocular angiogenesis and in diabetic retinopathy (DR) is not yet fully understood. The latest research data reveal a possible correlation of higher erythropoietin concentrations in the blood and in the eye with the development of more advanced stages of DR. The main aim of this work was to examine the possible influence of serum concentrations of erythropoietin on the development of diabetic retinopathy in patients with diabetes mellitus type 2.Methods The research involved 90 patients examined at the University Eye Clinic of the Clinical Center of Vojvodina, Novi Sad, Serbia. The first group comprised 60 patients with diabetes mellitus lasting for ten years or more, with diabetic retinopathy. The second, control group consisted of 30 healthy individuals. In the first group of 60 patients with diabetes, 30 of them had non-proliferative diabetic retinopathy (NPDR), and 30 had proliferative diabetic retinopathy (PDR). Laboratory EPO serum levels were determined, and they were correlated to the stage of DR. Concentration of EPO was assessed by ELISA method.Results The highest average concentration of EPO in serum (9.95 mIU/ml) was determined in the group of people with diabetes with PDR. The lowest average concentration of EPO in the serum (6.90 mIU/ml) was found in the control group. The average concentration of EPO in serum in the group of patients with diabetes with NPDR was 7.00 mIU/ml. The EPO concentration in serum was elevated in the group of PDR, and it was directly proportional to the level of the clinical stadium of PDR, being significantly higher in the moderate and severe subgroup of PDR comparing to the control healthy subjects, NPDR and mild PDR (p=0.007).Conclusions Significantly elevated serum concentration of EPO in the advanced stages of DR, and positive correlation between EPO serum concentration and clinical stages of PDR, suggest that erythropoietin represents an important growth factor from blood, which plays a significant role in retinal ischemia and angiogenesis in diabetic retinopathy, especially in the proliferative stage of this disease.
Serum-to-urine renalase ratio and its differences between healthy adults and chronic kidney disease patients
Authors: Serwin Natalia Maria , Wiśniewska Magda , Cecerska-Heryć Elżbieta , Safranow Krzysztof , Skwirczyńska Edyta , Dołęgowska Barbara 
Published: November 2019

Abstract
Background: Renalase is a flavoprotein that plays a protective role in chronic kidney disease and cardiovascular diseases. The secretion and way of action of this protein are still discussed. The aim of our study was to estimate the balance between serum and urine renalase in healthy individuals and chronic kidney disease (CKD) patients, using two parameters: fractional excretion (FE) and serum-to-urine renalase ratio (StURR).
Methods: Our study involved 28 healthy volunteers and 62 patients with CKD in stages I to IV. The concentration of renalase in serum and urine was measured using an enzyme-linked immunosorbent assay (ELISA) kit (EIAab, Wuhan, China). We analyzed associations between renalase levels in urine and serum, and other parameters: sex, age, GFR, presence of hypertension, diabetes, and proteinuria, and determined the serum-to-urine renalase ratio and fractional excretion of renalase.
Results: Renalase and serum-to-urine ratio were significantly higher in CKD patients in comparison with the control group. Fractional excretion was lower in CKD patients but this difference did not reach the statistical significance (p=0.092). Multivariate analysis performed in the CKD group showed, that from mentioned parameters, serum renalase was the only significant independent factor strongly positively associated with urinary renalase concentration.
Conclusions: The serum-to-urine ratio is significantly and about 6.5-fold higher in CKD patients, and the fractional excretion of renalase is 3-fold, but not significantly lower in CKD patients. Renalase levels in both serum and urine are not related to glomerular filtration rate and not associated with blood pressure.
Metabolic alterations provide insights into Stylosanthes roots responding to phosphorus deficiency
Authors: Luo Jiajia , Liu Yunxi , Zhang Huikai , Wang Jinpeng , Chen Zhijian , Luo Lijuan , Liu Guodao , Liu Pandao 
Published: November 2019

Abstract
Background: Phosphorus (P) deficiency is one of the major constraints limiting plant growth, especially in acid soils. Stylosanthes (stylo) is a pioneer tropical legume with excellent adaptability to low P stress, but its underlying mechanisms remain largely unknown.
Results: In this study, the physiological, molecular and metabolic changes in stylo responding to phosphate (Pi) starvation were investigated. Under low P condition, the root growth in stylo was significantly enhanced, which was accompanied with up-regulation of expansin genes participating in cell wall loosening. Metabolic profiling analysis showed that a total of 256 metabolites with differential accumulation were identified in stylo roots responding to P deficiency, which mainly include flavonoids, sugars, nucleotides, amino acids, phenylpropanoids and phenylamides. P deficiency led to significant reduction in the accumulation of phosphorylated metabolites (e.g., P-containing sugars, nucleotides and cholines), suggesting that internal P utilization was enhanced in stylo roots. However, flavonoid metabolites, such as kaempferol, daidzein and their glycoside derivatives, were significantly increased in P-deficient stylo roots. Furthermore, the transcripts of various genes involved in flavonoids synthesis were found to be up-regulated by Pi starvation in stylo roots. In addition, the abundance of phenolic acids and phenylamides was significantly increased in stylo roots during P deficiency. The enhanced accumulation of the metabolites in stylo roots, such as flavonoids, phenolic acids and phenylamides, might facilitate P solubilization and cooperate with beneficial microorganisms in rhizosphere, and thus contributing to P acquisition and utilization in stylo.
Conclusions: These results suggest that stylo plants cope with P deficiency by modulating root morphology, scavenging internal Pi from phosphorylated metabolites and enhancing accumulation of flavonoids, phenolic acids and phenylamides. This study provides valuable insights into the complex responses and adaptive mechanisms of stylo to P deficiency.