bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural Inversion, Reactivation and Extensional Detachment and Their Influence on the Formation and Preservation of Hydrocarbon Accumulations in Northern Western Desert of Egypt
Authors: Sun Ziming 
Published: February 2021

ABSTRACT
The northern Western Desert Basins of Egypt experienced a complex evolutionary history and several transformation of tectonic stress field properties. An integrated analysis of geological and geophysical data reveals that structural inversion, reactivation and extensional detachment develop in the area, and have a significant effect on formation and preservation of hydrocarbon accumulations. Such an analysis is paramount for prospect evaluation, risk mitigation, and therefore improving the exploration success rate.
The rifting in Jurassic and early Cretaceous formed several faulted-depression basins with boundary normal faults in the area. A few boundary normal faults were reactivated in late Cretaceous to Eocene period as reverse faults with dextral compressive features, giving birth to a series of inverted anticlines over them. Compressive wrenching movement on the boundary faults greatly weakened their lateral sealing capacity and accordingly enhanced the vertical conduit capacity of hydrocarbon migration from the Jurassic source kitchen to Cretaceous inverted anticlines along the boundary faults. This is why Cretaceous inverted anticlines show a high concentration of hydrocarbon accumulations whereas there are few oil discoveries in the lower Alam El Bueib (AEB) formation and Jurassic along the boundary faults.
Reactivation of basin boundary normal faults in late Tertiary to present abounds in the area. Most of them are surface penetrating, which are vital to the existing hydrocarbon accumulations because the reactivation could not only make poor the preservation of the existing hydrocarbon accumulations and cause the redistribution of hydrocarbons, but also it would destroy the existing hydrocarbon accumulations. Some unsuccessful wells can be attributed to the reactivation of basin boundary normal faults in late Tertiary to present. Some prospects associated with the reactivation of basin boundary normal faults have the same or similar hydrocarbon preservation risks as the unsuccessful wells.
By integrating seismic interpretation and lithologic assemblage and thickness variation of the AEB formation, an extensional detachment fault was recognized in Alamein Basin. The detachment, located in the mudstone-dominated AEB 5-6 intervals, makes hydrocarbon migration difficult from Jurassic source kitchen to Cretaceous traps because the vertical migration pathways have been cut off by it, and are unfavorable for the formation of hydrocarbon accumulation above it.
Innovations in Carbon (iv) Oxide Capture and Sequestration for Operations, Engineering and Technology
Authors: Lilian Simiyu E. , Konez Sandra 
Published: February 2021

ABSTRACT
Fossil fuel combustion supplies more than 85% of energy for industrial activities and thus it is the main source of greenhouse gases in the form of CO2. This is expected to remain unchanged for a long time as the world energy consumption doubles. Renewable energy is often a better option since it is environmental friendly but its technologies are not financially available for most countries. Carbon (iv)oxide capture and sequestration (CCS) is necessary for meaningful greenhouse gases reduction in the immediate future. CCS could reduce emissions by 19%. This is an important bridge between our lifestyle and an environmental friendly world. The components of CCS system include; capture (separation and compression), transport, injection and finally monitoring.
Power plants which are gas and coal fired are the main source of CO2. Other candidate sources include; cement production plants, refineries, petrochemical industries, oil and gas processing firms and natural gas wells
The methods of capturing CO2 are pre-combustion, post-combustion and oxy-combustion/oxy-fuel.
Possible sequestration places for the captured CO2 include; geological storage, for example depleted oil and gas reservoir, enhanced oil recovery, un-minable coal seams and deep saline formations, ocean storage, mineral carbonation and algal growth. Each of the methods above have their advantages and shortcomings as discussed in the research paper.
CO2 can be utilized in various ways like, conversion into renewable fuels, formic acid, syngas, methane and methanol, utilizing CO2 as a feedstock for organic and inorganic carbonates, urea and biodegradable polymers as well as non-conversion use of CO2 for example as a geothermal fluid, used in enhanced oil recovery and beverage making. The challenges of CCS are; high cost of capture transport and injection, environmental and safety, subsurface uncertainty, legal and regulatory issues. Trappings contribute to storage of CO2 in a site. They include; Structural and stratigraphic, residual, solubility, mineral trappings.
In conclusion, an approach that integrates different methods of capture and storage of CO2 may be a practical solution for CCS.
A Case Study of the Successful Deployment of Tractor Conveyed Perforation in Highly Inclined Well
Authors: Isehunwa Oloruntoba , Eze Joy , Ogunrinde Ademola , Boms Allen Aka 
Published: February 2021

ABSTRACT
Well A is one of the only two wells on the XY reservoir structure providing the optimum drainage point on that reservoir. However, Well X had been shut in due to high sand production and had been flagged as ‘non-integral’ with regards to SPDC Well Integrity Management (WIM) policy due to its faulty Tubing Retrievable Surface Controlled Subsurface Safety Valve (TRSCSSSV). The well was thus scheduled for repairs.
The objective of the workover operation as with most others done in SPDC was to restore integrity of the well, remediate sand control and improve production across the XY reservoir.
On re-entry into the well, a mechanical restriction was met in the high angle section of the well thus impeding access to drain hole. A review of the situation, showed a possible collapse of the lower completions (sand screen) possibly due to high sand production. An attempt at sand clean-up was futile.
This paper describes the unconventional but successful deployment of wireline conveyed perforation gun on tractor in SPDC to perforate this highly deviated well, thus, providing drainage access and recovering 2.14 MMstb of oil and 0.79 BScf of associated gas.
Amongst several options including the use of coiled tubing or wireline as means of perforation, the tractor conveyed guns stood out for a highly inclined well such as Well A. The Well Tractor functions with an electric over hydraulic power relationship and uses its wheel section to push the passenger tool downhole as cable is fed off the electric line unit. The make-up of the tractor conveyed system makes it suitable for high angle wells while providing a cost savings over other systems.
Practical Experience in Rig Move and Workover Operations in an Amphibious Terrain: A Case Study of Escravos Beach Rig Move and Workover Operations
Authors: Eze Joy , Onakomaiya Oluwarotimi , Ogunrinde Ademola , Adegboyega Olusegun , Wopara James , Timibitei Fred , Ideh Matthew 
Published: February 2021

ABSTRACT
The exploration and production of oil and gas mostly occurs in remote locations, so as to minimize human exposure and Health Security Safety and Environment (HSSE) risks. Shell Companies in Nigeria is not any different having operated for over 50 years in Nigeria with the largest footprint of all the international oil and gas companies operating in the country spanning over land, swamp, shallow waters and offshore terrains. Shell Petroleum Development Company, the operator of a joint venture (the SPDC JV) between the government-owned Nigerian National Petroleum Corporation – NNPC (55% share), Shell (30%), Total E&P Nigeria Ltd (10%) and the ENI subsidiary Agip Oil Company Limited (5%) focuses mostly on onshore and shallow water oil and gas production in the Niger Delta with about 60+ producing oil and gas fields and a network of approximately 5,000 kilometers of oil and gas pipelines and flow lines spread across the Niger Delta.
Escravos Beach is over 60km from the closest major city, Warri, a major oil and gas zone in the Niger Delta. It is bounded by the Escravos River to the East, Chevron canal to the North and the Atlantic Ocean to the South and is covered with predominantly mangrove forest especially along the creeks and consists of a number of natural and man-made waterways (rivers, creeks and canals).
Unlike most other onshore operations, this location can only be accessed via the waterways; thus requiring the rig equipment and every other equipment to be channeled via the waterways and subsequently on land to arrive at the site. The amphibious nature of this operation requires a combination of onshore and swamp requirements with increased HSSE exposure, logistics requirement and cost. This paper aims to highlight the practical experience garnered in the rig move and workover operations of Rig XYZ which operated in the Escravos Beach region.
Cost-Effective Directional Drilling and Logging-While-Drilling Operational/Maintenance Model Aids an East Africa Operator to Deliver Its Remote Location Exploration Campaign
Authors: Lunney Iain 
Published: February 2021

ABSTRACT
In a cost-sensitive market driven by depressed commodity prices, significant capital challenges exist for operators interested in pursuing exploration activities in remote environments to define their producible reserves. This paper explores the organizational and operational model developed by a service company over several remote area mobilizations; this model resulted in an optimized low-cost service delivery model characterized by top quartile operational key performance indicators (KPIs). The model centralizes critical functions of an operational organization into discrete service units that are located near the operational location or that provide remote assistance with communication and reporting lines in place to function effectively. Top quartile operational performance and tool availability is a result of placing a remote repair and maintenance facility that includes containerized specialty modules near the operational area. The upfront bottomhole assembly engineering, 24/7 monitoring, and proactive feedback of logged data, drillstring dynamics, and wellbore hydraulics are performed by a core team of subject matter experts in their respective disciplines from an established centralized operating center. The operational KPIs over the course of the six well exploration campaign provided substantial evidence to support the reliability of the model and the high level of experience used in both the remote maintenance facility and the operations center support team.
Novel Well Flow-Control Valve for Flexible Well Completion and Application in Commingled Production of Oil and Gas in West Africa
Authors: Bagal Joseph , Hallaire Maximilien , Hazel Paul 
Published: February 2021

ABSTRACT
This paper presents the development, qualification and field trial of a novel well flow valve that delivers unlimited zonal selectivity in single skin lower completion without the use of control lines. Control lines have limitations and risks due to complexity during deployment, restrictions on the number of zones, complications with liner hanger feed thru and associated wet connects. It is desirable to remove the control lines whilst maintaining the functionality of multi zone, variable choke flow control.
The well flow valve is a full-bore, reliable and robust mechanically operated sleeve, qualified in accordance with ISO14998 including multiple open/close cycles, at a sustained unloading pressure of 1,500 psi, with highly customizable flow ports.
The need for such a solution was identified by an operator in West Africa. The well objective was elevated from a gas producer to a well that required the flexibility to produce gas or oil with gas lift capability. The well flow valve was selected and required on site variable choke capability for both oil and gas production, with choke position verification, ability to handle dirty gas production without risk of plugging, compliant with a high rate and high pressure proppant frac along with ease of operation and long term reliability.
The field trial included a high pressure proppant frac in the oil zone. In the shallower gas zone, three well flow valves were used to deliver variable choking capability from maximum gas flow rate with minimal delta P adjusting down to a choke size suitable for gas lift. The well flow valves were operated using a high expansion shifting key conveyed on eline through the 3 ½" production tubing. The shifting key expanded in the 4 ½" lower completion to open/close individually all the well flow valves in a single trip. Incorporating this new product overcame the challenges presented and met the objective of commingled production of oil and gas. The well flow control valve demonstrated flexibility through design, supply chain, manufacturing, and operations. This paper will also outline the future road map covering further developments of the well flow valve and its incorporation into an enhanced flexible lower liner solution aimed at lowering well completion costs and risks.
The Risk of Stroke after Acute Myocardial Infarction in Patients with and without Atrial fibrillation: A Nationwide Cohort Study in Taiwan
Authors: Chiang Cheng-Hung , Hung Wan-Ting , Huang Wei-Chun , Lin Kun-Chang , Cheng Chin-Chang , Kuo Feng-Yu 
Published: February 2021

Abstract
Background
Both acute myocardial infarction (AMI) and atrial fibrillation (AF) are risks for stroke. The risk of stroke after AMI may be different in patients with or without AF. The aim of this study was to evaluate the impact of AF on stroke in patients after first AMI.
Methods
This is a retrospective nationwide cohort study. A total of 170,472 patients who had the primary diagnosis of first AMI between 2000 and 2012 were enrolled. Among them, 8,530 patients with AF were identified. Propensity score matching technique was used to match 8,530 patients without AF with similar ages and genders. All patients were followed until stroke or 31 December 2012, whichever occurred first. Kaplan–Meier cumulative survival curves were constructed to compare stroke between AMI patients with and without AF.
Results
Overall, 12-year stroke rate was higher in patients with AF than without AF (log rank P-value < 0.001), including in different genders, ages, or intervention subgroups. In patients with AF, those with preexisted AF had higher stroke rates in male gender, age below 65 years, and with intervention subgroups than those with new-onset AF. In Cox proportional-hazard regression analysis, AF was an independent risk factor for stroke after first AMI (hazard ratio, 1.67; 95% confidence interval, 1.5–1.87).
Conclusions
AF significantly increased stroke risks after first AMI. In patients with AF, those with preexisting AF have higher stroke risks in male genders, ages below 65 years, and with interventions than those with new-onset AF.
The C2-symmetry colorimetric dye based on a thiosemicarbazone derivative and its cadmium complex for detecting heavy metal cations (Ni2+, Co2+, Cd2+, and Cu2+) collectively, in DMF
Authors: Hishimone Phillipus N , Hamukwaya Eunike , Uahengo Veikko 
Published: February 2021

Abstract
The field of chemosensing has been experiencing an exponential expansion in recent times, due to increased demands for simpler and user-friendly analytical techniques, in order to combat and confront the challenges of industrial pollutions in the 21 st century. Metal complex-based chemosensors have received little attention while exhibiting excellent sensing properties, comparing to their organic counterparts. Thus, a thiosemicarbazone-based ( H ) and its cadmium complex ( P ) were synthesized, characterized and their photophysical and chemosensing properties were investigated in DMF solvent. The addition of molar equivalents of selected cations (of nitrates or chloride salts) to H and P , produced visually detectable colour changes as well as remarkable spectral shifts. Explicitly, the two probes ( H and P ) were able to collectively discriminate heavy metal cations such as Cd 2+ , Co 2+ , Zn 2+ , Cu 2+ , Ni 2+, and Ag + , both in DMF, among all other heavy metal cations tested. None of the anions could be detected by H or P , even when the tetrabutylammonium salts (TBAs) were used, the action presumably ascribed to the solvent effect. Thus, H and P can be used to selectively and sensitively detect the presence of heavy metal cations, via naked-eye detectable colour changes in an aqueous soluble solvent such as DMF.
Cloning and characterization of the DIR1 promoter from Eucommia ulmoides Oliv and its response to hormonal and abiotic stress.
Authors: Ziyun Li , Biao Li , yichen Zhao , Degang Zhao 
Published: February 2021

Abstract
The lignans of Eucommia ulmoides have been extensively studied and shown to have a dual mechanism of regulating blood pressure. Studies have shown that DIR1 is a key gene in the biosynthetic pathway of lignans in Eucommia ulmoides Oliv. In this study, a 2000 bp upstream promoter sequence was cloned, and part of the sequence (1495 bp) and its 5'-end truncated segment were constructed into the pCAMBIA1391Z expression plasmid upstream of ß-glucuronidase (GUS). Agrobacterium-mediated genetic transformation produced stable transgenic tobacco lines. The results showed that although both full-length and truncated promoters could initiate GUS expression, their levels were influenced by the degree of deletion at the 5' end. GUS histochemical staining showed that the core promoter region was located in the region containing the transcription initiation site (TIS) within 212 bp. In addition, the DIR1 promoter responded to environmental and hormonal stressors, such as jasmonic acid (MeJA), abscisic acid (ABA), D-mannitol (drought mimic), and high concentrations of NaCl. In transgenic tobacco seedlings, MeJA, D-mannitol, and ABA could activate the DIR1 promoter, whereas high concentrations of NaCl could inhibit it. In E. ulmoides Oliv seedlings, MeJA, NaCl, and D-mannitol activated the DIR1 promoter, whereas ABA had an inhibitory effect. In summary, our findings provide a theoretical basis for the use of the DIR1 promoter in plant genetic engineering, indicating its potential. Our study also presents novel insights for lignan biosynthesis and sheds light on the mechanisms of E. ulmoides Oliv in response to stress.
Numerical Design and Frequency Response of all group-IV alloys based MQW Transistor Laser
Authors: Ranjan Ravi , Pareek Prakash , Das Mukul Kumar , Pandey Saurabh Kumar 
Published: February 2021

Abstract
In this work, a theoretical model is developed for n-p-n mid-infrared transistor laser (TL) with strain-balanced Ge0.85Sn0.15 multiple quantum well (MQW) structure in the base. Variation of optical confinement factor, modal gain and threshold current density have been rigorously investigated for different number of QWs (N) in MQW structure. The result shows that overall optical confinement factor and modal gain increase with N. The frequency response of MQWTL for common base (CB) configuration is estimated from small signal relationship between the photon density and emitter current density by solving laser rate equation and continuity equation considering the virtual states as a conversion mechanism. Increment of N causes modulation bandwidth to initially increase and then decreases with N, which reveals a shifting of device nature for higher values of N. The results also suggest that on judicious selection of N, the proposed device can become a viable monolithic light source.
The Effects of Ionotropic GABA Receptor Blockage on Brain in Sepsis-induced Rats
Authors: Ates Gulten , Ozkok Elif , Gundogan Gul Ipek , Tamer Sule 
Published: February 2021

Abstract
Encephalopathy develops following sepsis, which is defined as life-threatening organ failure due to the irregular response of a host to infection. It has high mortality and morbidity rates. In this study, we aimed to investigate the effects of inflammation on brain tissue, and the effects of the GABAA receptor antagonist bicuculline in rats with sepsis. Sepsis was experimentally generated in rats using LPS. The rats were divided into four groups as control, LPS (10 mg/kg i.p.), bicuculline (1.5 mg/kg bicuculline methiodide s.c.), and LPS + bicuculline. Electrophysiologic recordings and body temperature measurements were completed at the 24th hour after injection, and blood samples were taken from the heart for measurements of biochemical parameters. TNF-α, IL-10, and GABA levels were measured using ELISA, and MDA levels were measured using the Bouge method from brain tissue. Tissue imaging was performed with S100-ß, NEUN, and synaptophysin antibody using immunofluorescence staining. One-way ANOVA and the Tukey test were used in statistical analysis. Inflammatory parameters increased in brain tissue in the LPS group compared with the control group. The immunofluorescence staining results in brain tissues were as follows: S-100ß involvement increased, and NeuN and synaptophysin involvement decreased in the LPS group. In electrophysiologic recordings, activity consistent with acute non-focal seizures was observed in the LPS group; however, it was consistent with the resting status in other groups. We suggest that the GABAA antagonist bicuculline methiodide may be a prophylactic agent in sepsis, which caused the impaired neurotransmitter balance, increased pro-inflammatory cytokine and lipid peroxidation, and decreased anti-inflammatory cytokine levels.
Tilt illumination for structured illumination imaging
Authors: Jin Xin , Ding Xuemei , Tan Jiubin , Shen Cheng , Zhou Xuyang , Liu Shutian , Liu Zhengjun 
Published: February 2021

Abstract
To achieve super-resolution imaging, the information in higher frequency of the observed sample is collected by illuminating with a structure beam for a limited optical transfer function (OTF). In this paper, tilt illumination mode is introduced to structured illumination microscopy (SIM) for enhancing lateral resolution. More sample spectrum more than traditional SIM, can be obtained by detector. Thus, SIM with tilt illumination can be improved at the aspect of lateral imaging resolution.