bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitivity Testing of Stereophotoclinometry for the OSIRIS-REx Mission. II. Effective Observation Geometry for Digital Terrain Modeling
Authors: Palmer Eric E. , Weirich John R. , Gaskell Robert W. , Lambert Diane , Campbell Tanner , Drozd Kris , Barnouin Olivier S. , Daly Michael G. , Getzandanner Kenneth , Kidd John N. , Adam Coralie D. , Lauretta Dante S. 
Published: February 2024

Abstract
The OSIRIS-REx mission used stereophotoclinometry (SPC) to generate digital terrain models (DTMs) of its target asteroid, Bennu. Here we present a suite of preflight tests conducted to identify the observing geometry and number of images needed to create DTMs that would enable successful navigation around and to the surface of the asteroid. We demonstrate that high-quality DTMs can be generated by using only five images: four that are focused on topography, in which the spacecraft’s viewing geometry brackets the target (north, south, east, and west), and a fifth that measures the target’s albedo variation, taken from near local noon. We further show that the first 10 iterations of the SPC process can meaningfully improve DTM quality, including in the case of a suboptimal input image set, whereas after 10 iterations the DTM quality approaches an asymptotic maximum. We distill our findings into recommendations for observation planning that can be applied by other missions intending to use SPC to model the shape and terrain of their target.
Leveraging the Gravity Field Spectrum for Icy Satellite Interior Structure Determination: The Case of Europa with the Europa Clipper Mission
Authors: Cascioli G. , Mazarico E. , Dombard A. J. , Nimmo F. 
Published: February 2024

Abstract
Understanding the interior structures of icy moons is pivotal for addressing their origins and habitability. We introduce an approach employing the gravity field spectrum as an additional constraint for the inversion of differentiated icy bodies’ interior structures. After developing the general methodology, we apply it to Europa, utilizing the predicted measurement capability of NASA’s Europa Clipper mission, and we prove its effectiveness in resolving key geophysical parameters. Notably, we show that using the gravity field spectrum in combination with the mass and moment of inertia of the body allows us to estimate, depending on the considered end-member interior structure, the hydrosphere thickness with 4–20 km uncertainty and reliably determine the seafloor maximum topographic range and elastic thickness to within 100–600 m and 5–15 km, respectively, together with the power–degree relationship of the seafloor topography. We also show that the proposed method allows us to determine the density of the silicate mantle and the radius of the core to within 0.25 g cc−1 and 50 km, respectively.
Accuracy and Reproducibility of Virtual Reality Perimetry in Children
Authors: Pruett Jaron K. , Linton Edward F. , Donahue Sean P. , Groth Sylvia L. 
Published: February 2024

Purpose:
To determine normal threshold values for the 24-2 program of the VisuALL-K (Olleyes, Inc), a portable static automated virtual reality perimeter that uses a video game–based testing modality on an updated version of the algorithm and to repeat the test to assess retest variability.

Methods:
This prospective cohort study included 19 participants (aged 8 to 17 years) with healthy afferent systems. Participants performed two 24-2 automated perimetry tests on the virtual reality perimeter device.

Results:

Mean age was 12.7 ± 2.5 years; 53% were boys and 47% were girls. Mean test location threshold was 30.5 ± 4.0 dB for test 1 and 31.3 ± 2.8 dB for test 2. Sensitivity decreased with eccentricity as expected (−0.17 dB per degree). Bland-Altman analysis showed a repeatability coefficient of ±5.1 dB for mean deviation, meaning that 95% of retest values were within ±5 dB of the threshold value for the first test. Higher thresholds for the first test regressed toward the mean values in the second test, indicating a learning effect. Intraclass correlation coefficient for mean deviation between test 1 and test 2 was 0.70 (0.55 to 0.80,
P
< .0001). Mean time to completion for the virtual reality perimeter was 5.1 ± 1.5 min/eye.

Conclusions:
The VisuALL-K virtual reality perimeter provided an assessment of the visual field in normal children aged 8 to 17 years. A shallow hill of vision was demonstrated. A notable learning effect was demonstrated, with repeatability difference wider than other published head-mounted display perimeters.

[
J Pediatr Ophthalmol Strabismus
. 2024:61(4):262–266.]
Remaining Oil Distribution and Potential Tapping During High Water-Cut Stage in Offshore Bottom Water Fault Block Reservoirs
Authors: Yang W. , Chen J. , Kang K. , Wang S. , Zhang Z. 
Published: February 2024

Abstract
CFD oilfield is an offshore structural bottom water reservoir located in the Bohai Bay basin. The oilfield is developed by horizontal wells. After the high water cut of the oil wells, all oil producing wells are converted into reinjection wells to meet the needs of the production of the oilfield group. After more than 10 years of high intensity water injection, the injection volume has exceeded 20 times of geological reserves.
In order to understand the distribution law of water-flooded and remaining oil in this reservoir, we introduced the relative permeability time-varying characterization into the reservoir numerical simulation on the basis of large-scale physical simulation experiments, quantitatively described the evolution process of water ridge shape below the horizontal well and its internal oil displacement efficiency with time and injection volume during the production and water injection process of the bottom water reservoir, and finally predicted the current residual oil distribution law.
According to the research results, when the injection volume of a single well is 5 times, 10 times and more than 20 times of the well control reserves, the radius of the water ridge below the horizontal well is&lt;200m, 250~350m and&gt;450m respectively. This conclusion is confirmed by several passing wells and the current distribution of remaining oil is basically consistent with the research prediction. Under the guidance of research conclusions, we have developed an overall plan for inter-well infilling to tap the potential again and have achieved excellent results. During the implementation of this plan, many wells have achieved high production of more than 300 m3/day at the initial stage. It is predicted that the recovery efficiency of this reservoir will increase by 11 percentage points.
A Comprehensive Simulation Study of Polymer Enhanced CO2 Injection in Light Oil Reservoirs
Authors: Laochamroonvorapongse Rapheephan , Srisuriyachai Falan , Chewaroungroaj Jirawat , Srisuriyon Jantakan , Henglai Puntira 
Published: February 2024

Abstract
Water-Alternating-Gas (WAG) injection has been widely implemented to improve volumetric sweep efficiency from gas injection alone. However, the WAG still suffers from gravity segregation, especially in thick and heterogeneous reservoirs with large well spacing. This study aims to investigate suitable Enhanced Oil Recovery (EOR) injection strategies for light oil reservoirs in Southeast Asia. The new injection techniques, such as Polymer-Alternating-Gas (PAG) and co-injection of CO2 with water/polymer, are also included.
The study uses the real geological model in Thailand's oilfield and the INTERSECT software to fully integrate the physics modeling of fluid composition and polymer properties. The reservoir oil is characterized based on actual PVT data and has a viscosity of 0.3 cP at reservoir conditions. The injection strategies performed in this study are water, polymer, CO2, WAG, PAG, co-injection of CO2 and water, and co-injection of CO2 and polymer. The sensitivity of CO2 injection rate, WAG sequences, and polymer concentration on recovery efficiency are also investigated.
Various EOR injection strategies are evaluated by using the history-matched model and compared with a waterflood case. The continuous CO2 injection at 4 MMscf/D yields an additional oil recovery factor of approximately 2.7%. The co-injection of CO2 with water and polymer can recover the oil additionally from waterflood by 3.0% and 2.9%, respectively. The benefit of co-injection methods is that the water/polymer co-injection helps maintain reservoir pressure after gas breakthrough at producers. Due to the reservoir dipping, the CO2 injection from updip location is promising because of the gravity-assisted effect. From the sensitivity analysis, the increase in CO2 injection rate from 4 to 8 MMscf/D results in propagation of gas farther from injection wells, leading to an additional RF gain of 0.6%. The different WAG injection sequences can be implemented at each WAG injector to fully utilize the gas compressor and maintain the constant volume of gas injection.
This study examines the existing and new CO2-EOR injection techniques for multi-layered light oil reservoirs with dipping. The pre-selected injection strategies can be further investigated in the optimization study of oil recovery and CO2 storage.
Experimental Investigation of the Effectiveness of Cement Expansion Additives for Improved Abandonment of High Rate Gas Wells
Authors: Amra A. 
Published: February 2024

Abstract
Cement expansion tests performed on slurries used in cementing and abandoning of Oil and Gas Wells are done to ensure no micro-annuli develop post cement setting which leads to gas bubbles (seepage) on surface post abandonment – this was the case in one abandoned Well from few decades back.
Industry use API ring mold testing to ensure cement expands post setting to overcome cement shrinkage issue. To ensure best in class, industry leading abandonments, Operator performed – in additional to API Test – additional extensive cement expansion testing in the Operator lab. Testing utilized novel advanced cement expansion measurement setups which simulate cement setting at downhole conditions of pressure and temperature using small and large cement plug sizes.
This study calculated permeabilities of various cement abandonment plugs recipes with different expansion additives. Results were then compared to API ring mold testing for same slurries at surface and downhole conditions. Comparison concluded that expansion results obtained from API ring tests didn't match testing performed at STCA. In another words, Cement Expansion Additives which showed acceptable expansion percentage with API ring mold test, proved to result in permeability below NORSOK abandonment thresholds, and not to always yield the required expansion pressures when tested in the large-scale downhole conditions’ setup.
Hence API ring mold tests which are widely utilized by the Oil and Gas industry are not fully representative of downhole conditions and give inaccurate representation of cement expansion and sealing ability.
Ending With a High Note: Striving for Safe and Resilient Well Abandonment Through Geomechanics-Driven Cap Rock Restoration Study
Authors: Zulkipli Siti Najmi Farhan , Shah Jamari M 
Published: February 2024

Abstract
Well abandonment is the last stage of well management life cycle post production cease and well shut in. Estimating field potential during the early appraisal stage, sustaining and enhancing the well productivity throughout the active producing years become the critical agenda to meet production target. Well healthiness and performance issues are easily identified through surveillance and well diagnostics surveys which continue till the end of well life including during well abandonment campaign if required. Reservoir pressure is one of the critical parameters monitored during this period to indicate production drive. The importance of pressure data will be emphasized during well abandonment stage together with cap rock evaluation for well barrier assessment.
Pressure survey during drilling execution and throughout production period till abandonment is used as critical input to evaluate the cap rock strength. Initial reservoir pressure with full gas evacuation from the reservoir are assumed to happen to determine the minimum setting depth for the cement plug where the gas line intersects with fracture gradient line. Competent cap rock interval must be identified below this threshold depth to allow for safe and adequate natural barrier in case of pressure increase. Pressure depletion element is also factored in the assessment of reservoir rock to further sensitive the depth range to set the cement plug.
Results indicate that out of 12 wells evaluated only one well requires cement squeeze directly into the existing perforation following the conventional well abandonment approach while the rest of wells are assured through the cap rock restoration assessment without any completion string below top packer removal required. This has translated to project cost optimization of USD 8 million. Systematic workflow process honouring the cap rock and geomechanics concepts are formulated as best practices for future project replication. In addition, systematic tabulation of pressure record, legacy cement bond log profile and well intervention history provide an elusive overview if any cement remedial job is required to re-establish the well barrier. A comprehensive track record allows few millions dollars of cost savings by eliminating additional cement bond log run and any new data acquisition run.
In conclusion, cap rock restoration technique backed with geomechanics-driven pressure analysis is able to provide for safe and reliable well abandonment portfolio. Doing the right analysis using the right data for the right application will help to strengthen technical integrity of subsurface evaluation work and ensure a more responsible way of abandoning the well for good.
Multiphase Hydrate Kinetics Model Extends Offshore Oil and Gas Field Operability
Authors: Davis I. M. , Makogon T. Y. , Khuraidah M. A. 
Published: February 2024

Abstract
An offshore oil and gas field undergoing a major production increment relies on a constant supply of Monoethylene Glycol (MEG) as protection against hydrate blockage risk. MEG supply pump trip would initiate an emergency shut down of the entire production system, both gas and oil. Novel hydrate research on hydrate growth rate was applied to estimate the survival time from loss of MEG to full pipeline blockage.
Hydraulic multiphase flow assurance transient modelling of both associated and nonassociated offshore gas gathering system was utilizing the novel hydrate kinetic module tuned to lab data for gas-dominated production systems. Analysis was performed considering different periods of total MEG loss and reinstatement, to predict hydrate formation volumes and hold-up within the gas network. In addition, periods of MEG under injection were considered, along with effects on ramp-down and subsequent ramp-up. Additional sensitivities were performed considering the ambient temperatures and changes to hydrate equilibrium curves. Finally, modelling parameters including hydrate cohesive/adhesive forces and prediction of entrainment of water were considered to ensure robust conclusions.
Temporary but complete MEG loss shows that hydrates begin to appear soon after MEG disruption, and hydrates tend, predominantly, to deposit on the pipe wall. The risk of a complete pipeline blockage after an 8-hour MEG disruption will depend on pipeline diameter and gas flowrate and composition. Small diameter flowlines transporting lean gas (no condensate phase), tend to accumulate hydrate faster due to the absence of the oil layer, giving greater contact between gas and water phase. Larger diameter trunk lines do not show any significant hydrate accumulation even after an extended level of MEG disruption. In most cases, hydrate accumulation will be eliminated during re-start of the MEG injection. The analysis allows identification of pipelines most at risk of hydrate blockage, and allows development of operating procedures to protect the system if loss of MEG occurs. Overall, it allows the specification of less conservative shutdown conditions and eliminates the potential loss of total field production by loss of MEG supply.
The analysis is based on experimental hydrates research from the University of Western Australia and is the first model developed specifically for gas dominated production fluids. It represents a previously unavailable methodology to predict evolution and distribution of hydrate phase within both fluid and pipe wall, time required for hydrates to first appear with loss of inhibition; the duration of hydrate accumulation to grow to a dangerous level and time for dissociation on restoration of MEG supply.
Application of a Flow Improver to Increase Production, Reduce Operating Cost and Carbon Emission at a Mature Oilfield
Authors: Phan T. , Yunus I. , Said A. , Mohamed W. , Makled M. 
Published: February 2024

Abstract
Production at the Neag-2 fields in the Western Desert of Egypt had been constrained by limited flow and pressure challenge in the multiphase pipeline that transferred produced fluids from Neag-2 fields to Neag-1 processing facility. The pipeline had a maximum allowable operating pressure of 47 bar and had been operated at a limited flow rate of about 14,000 barrels/day to maintain pressures at 40-41 bar to ensure pipeline integrity. Therefore, it was desired to have an effective chemical solution to reduce the pipeline pressure to 35 bar or less to allow the pipeline to transfer more production volumes from more wells with a target flow rate of 15,000 BPDs or higher. This paper presents laboratory test results to identify and recommend a flow improver that is effective in reducing pressure loss in a multiphase pipeline with high water cut and high TDS water. The results of a 10-day field trial showed that co-injection of both the flow improver FI-A at 24 ppm and the incumbent oil DRA at 10 ppm yielded the best performance with the pipeline pressure reduced to 34 bar and flow rate increased to 16,436 BPDs. Both values are exceeding target KPIs of pressure and flow rate, 15% increase compared to the corresponding baseline values. The trial results proved that flow improvers can be used to increase throughput of existing pipelines, eliminate bottle necks of production systems in mature fields to maintain or increase production, reduce operating cost, and provide ESG benefits in term of materials usage and carbon emission reduction.
Cardiac Papillary Fibroelastoma
Authors: Siddiqui Areeba , Rehman Sameer 
Published: February 2024

Background:
Cardiac fibroelastomas are exceedingly rare etiologies of stroke, increasingly recognized with better diagnostic modalities. Surgical excision is the only curative option; however, timing of heparinization for cardiac bypass remains a challenging decision.

Objective:
We present a case of a 56-year-old female, diagnosed with multiple posterior circulation strokes and a left atrial mass, who successfully underwent anticoagulation and resection in 1 week.

Material and Methods:
MRI of the brain demonstrated numerous embolic-looking posterior circulation strokes. Transthoracic echo was negative for atrial pathology; a transesophageal echo revealed a left atrial mass, histologically consistent with papillary fibroelastoma.

Results:
Resection was delayed for up to 1 week to allow safe heparinization. We present a unique case of embolic stroke of undetermined source (ESUS) arising from a histologically rare tumor.

Conclusion:
We make the case for extensive workup for evaluation of posterior circulation strokes, including TEE, as well as timely resection of cardiac tumors.
Comparative Study of Risk Factors and Cognitive Profile of Small- and Large-Vessel Vascular Dementia – A Clinic Based Study
Authors: Bhat Ashwani , Das Goutam , Mukherjee Adreesh , Mukherjee Diptasree , Gangopadhyay Goutam , Biswas Atanu 
Published: February 2024

Background:
Vascular dementia (VaD) is a clinically heterogeneous entity. There is a dearth of studies for comparison of the cognitive profile of cerebral small-vessel disease (SVD) with large-vessel disease.

Objective:
We planned to evaluate and compare the cognitive profile of SVD and large-vessel VaD and evaluate various risk factors associated with them.

Materials and Methods:
Patients of VaD were recruited after excluding mixed and ambiguous cases. Patients were classified into SVD and large-vessel VaD and analyzed for their clinic-epidemiological and cognitive profiles.

Results:
Among 76 patients, 48 (62.5%) have SVD and 28 (37.5%) have large-vessel disease. Hypertension (93.4%) was the commonest risk factor, followed by smoking (34.21%), hyperlipidemia (26.31%), and diabetes mellitus (DM, 22.36%). Hypertension (P < 0.05) and DM were common in SVD, whereas smoking, hyperlipidaemia, and cardiac diseases were common in large-vessel disease. Attention (77.1% vs 25%), executive function (68.8% vs 28.6%), and calculation (58.3% vs 32.1%) were significantly more impaired in SVD compared to large-vessel disease, whereas visuoperceptual (21.4% vs 6.3%), praxis (28.6% vs 4.2%), and gnosis (14.3% vs 2.1%) were significantly more impaired in large-vessel disease than in SVD. Disruption of frontal-subcortical connection was responsible for the cognitive profile in SVD, but in large-vessel disease, it resulted from the cumulative loss of function from different lesions.

Conclusions:
Despite having common vascular risk factors, few are more common in SVD than in large-vessel disease. The different clinical and cognitive profile is due to the diverse anatomical lesions in these two subclasses of VaD.
Survey of Family Satisfaction with Patient Care and Decision Making in Neuro-Intensive Care Unit- A Prospective Single Center Cross Sectional Study from an Indian Institute of Neurosciences
Authors: Bharadwaj Suparna , Umamaheswara Rao G S , Hegde Arjun , Chakrabarti Dhritiman 
Published: February 2024

Background:
Quality of health care is a major issue. Providing care that accommodates individual patient preferences and values is termed patient-centered care.

Objectives:
In this study, we assessed family satisfaction (FS) with intensive care unit (ICU) care and family satisfaction with decision making in the care of critically ill neurological/neurosurgical patients.

Materials and Methods:
The FS-ICU questionnaire was used to assess family satisfaction. Data were analyzed using frequency tables and rates.

Results:
Of the 154 FS-ICU questionnaires analyzed, the overall satisfaction rate with care was 59.97, with information needs was 56.52, and with decision making was 59.46. Lower satisfaction rates among families may be due to the highly morbid nature of neurological illness in their kin or due to differences in socioeconomic factors.

Conclusions:
Periodic audit of the FS questionnaire is useful in assessing the quality of health care in the neuro-ICU. Efforts to incorporate suggestions of study subjects may improve FS with patient care and decision making.