bluuebunny/crossref_metadata_2025 huggingface dataset:
Understanding the Dynamics of Matrix-Fracture Interaction for Suitable Fracturing Fluid Design and Chemical EOR in Unconventional Oil/Gas Recovery
Authors: Lin Lixing , Babadagli Tayfun , Andy Li Huazhou
Published: March 2024

The effects of chemical additives on mitigating water-blocking and improving oil recovery were experimentally examined for gas-water and oil-water systems in spontaneous imbibition cells. In these attempts, two factors are critically important: (1) Understanding the physics of the interaction, whether it is co- or counter-current, and (2) characteristics of the chemical additives to suitably orient the interaction for specific purposes (accelerate/decelerate matrix-fracture interactions). Co- and counter-current imbibition experiments were conducted on sandstone rock samples using various oil samples (viscosities between 1.37 and 54.61 cP) as well as gas (air). The selected new-generation chemical additives include deep eutectic solvents, cationic/anionic/nonionic surfactants, inorganic and organic alkalis. We observed that the functionality of the chemicals varied depending on the fluid type, interaction type (co- or counter-current), and application purposes. For instance, chemicals such as cationic surfactant CTAB significantly reduced water invasion into the gas-saturated sandstone cores during fracturing, while chemicals such as a nonionic surfactant (Tween 80) provided considerable oil recovery improvement in the oil-saturated sandstone cores. The surface tension and wettability of the rock surface are crucial factors in determining the suitability of chemicals in mitigating water blockage. In terms of the oil recovery, certain chemical additives, such as O342 and Tween 80, may result in a lower recovery rate in the early stage because their strong ability in IFT reduction but could lead to a higher ultimate recover factor by altering the wettability. Additionally, the introduction of chemicals resulted in notable spontaneous emulsification, especially in counter-current imbibition, thereby enhancing oil recovery. The spontaneous emulsification and its stability are influenced by factors such as oil drop size, boundary condition, interaction type, IFT, wettability, as well as rock surface charges. The results have implications for understanding the physics and dynamics of matrix-fracture interactions in co and counter-current conditions. Additionally, they offer practical insights for selecting appropriate chemical additives in hydraulic fracturing fluid design and enhancing oil recovery in unconventional reservoirs.
Dielectric Property Measurements in Frequency Domain of Water Saturated Clean and Oil Sands at Elevated Thermobaric Conditions
Authors: Kuznetcov I. , Kantzas A. , David S.
Published: March 2024

Electromagnetic (EM) irradiation is a relatively nascent, but promising oil recovery method. It is well-positioned to enable carbon-free oil production from heavy oil- and bitumen-rich formations. Unfortunately, this method has not been widely adopted yet due to a lack of understanding of the dielectric properties of oil-bearing rocks at elevated thermobaric conditions. The present work aims to bridge this gap by conducting dielectric property frequency spectra measurements of heated and pressurized "native" core samples.

A patented system was commissioned and a series of dielectric measurements of saturated oil sand core samples were performed in two successive heating-cooling cycles within the 20°C to 220°C range. The pore pressure was kept constant above steam saturation point for the first cycle and was purged by the second cycle's end to induce evaporation. Moreover, every measured sample was compacted by a load of 1000 psi (6.89 MPa). In addition, a comprehensive database management system was designed to facilitate automatic data acquisition of the time- and temperature-series of the relative dielectric constant and conductivity frequency responses.

The relative dielectric constant and the conductivity frequency spectra were found to be directly proportionate to temperature with some level of hysteresis between the heating and cooling cycle trends. To better visualize and interpret this behavior, three-dimensional maps of the dielectric properties in frequency-temperature domain were constructed. Singularities were observed in the results for the saturated clean and oil sand samples at certain resonant frequencies. Those frequencies signify extremums in the EM energy transfer to the formation. Increased values in the relative dielectric constant and decreased values in the conductivity at frequencies smaller than 1 MHz were attributed to the electrode polarization effect, which becomes more prominent at higher temperatures and concentration of dissolved solids. In all heating experiments of water saturated clean sands a full evaporation of the pore fluid was achieved, and the dielectric properties would approach the properties of air. However, no steam desiccated zones were observed in the oil sand samples. As a result, the local concentration of ions, minerals and other solids present in the pore fluid increased, which was further confirmed by the increase in the measured dielectric properties.

To the best of the authors’ knowledge this was the first time the dielectric measurements of "native" oil sand sample cores that make up most heavy oil- and bitumen-bearing formations in Athabasca region, were performed in variable temperature-pressure-steam quality environments. These measurements should provide better means to modelling of electromagnetic energy dissipation in different parts of the formation and forecasting oil production by relevant EM heating methods.
Scaled Physical Modeling of Cyclic CO2 Injection in Unconsolidated Heavy Oil Reservoirs Using Geotechnical Centrifuge and Additive Manufacturing Technologies
Authors: Perez Daniel Cartagena , Shokri Alireza Rangriz , Zambrano Gonzalo , Pantov Dymtro , Wang Yazhao , Chalaturnyk Rick , Hawkes Chris
Published: March 2024

The success of CO2 injection in shallow reservoirs such as CHOPS (Cold Heavy Oil Production with Sands) entails an understanding of the complex interplay of mechanics of gaseous solvent interaction, reservoir deformation, and borehole collapse. This paper provides the design of a highly-instrumented scaled laboratory experiment inside a 2-meter radius beam geotechnical centrifuge, capable of simulating the cyclic CO2 injection into an unconsolidated sandstone specimen at reservoir conditions.

Given that sand production during CHOPS creates high-permeability channel-like structures, additive manufacturing technology (i.e. 3D printing with actual sand particles) was used to fabricate the physical model specimen of a scaled reservoir. A centrifuge cell was designed and constructed to simulate the multi-phase cyclic CO2 injection process at the reservoir scale. Scaling factors for stress, time, height and density were used to determine the centrifuge operation. A loading system was included in the centrifuge cell to emulate the vertical stress from the overburden rocks at the top of a shale caprock layer. Stress anisotropy in horizontal stresses were applied through an 8-arm horizontal loading system, similar to a true triaxial cell. A sand trap and a production unit were used to collect the collapsed sands and the produced fluids.

To establish residual water saturation, the reservoir prototype was first saturated with water, followed by dead canola oil and live oil (prepared by dissolving CO2). The experiment was started by spinning the 500 kg setup inside the geotechnical centrifuge until it reached a steady rotational speed of 120 revolutions per minute (equivalent to 30 times the gravitational acceleration). The perforations of a scaled wellbore within the reservoir prototype were opened to initiate fluid and sand production. It appeared that the increase in the cohesion of the 3D printed rock in regions away from wellbore reduced rock failure during production cycles even with large seepage forces and pressure gradients. The structural changes around high-permeability zone and near-wellbore region were related to stress concentration.

The result of our scaled physical experiments delivers insights on fluid displacement and rock deformation during CO2 saturated oil production from a reservoir prototype. The application of a geotechnical centrifuge and additive manufacturing technology provides a platform to experimentally explore the multi-scale, multi-physics processes of sampling, flow, and deformation issues observed in subsurface systems including H2 storage and safe disposal of radioactive waste.
Geomechanical Modeling and Minimum Fracture Pressure Prediction of CO2 Storage Reservoir Caprock in the Lloydminster Area
Authors: Shen Chen , Li Ze , Chang Yuanhao , Zhang Baoxin , Zeng Fanhua
Published: March 2024

Acknowledging the critical imperative to reduce CO2 emissions globally, there is a heightened drive towards adopting the preferred CCUS technology to achieve sustainable greenhouse gas reduction. CCUS requires a reliable caprock integrity to prevent CO2 migration and ensure the success of the injection program. Nevertheless, the impact of mineralogical alterations on caprock integrity continues to elude comprehensive understanding through research. This study investigates the evolution of caprock integrity resulting from long-term CO2 storage-induced mineralogical changes. A 2D Voronoi model is developed to predict the minimum fracture pressure of sideritic shale caprocks with varying mineral compositions in the Waseca heavy oil formation, Canada. The numerical simulations are validated against geomechanical test results, showing good agreement. Sensitivity analysis reveals visible variations in the plastic deformation process due to CO2-water-rock reactions and mineral transformations. Results indicate that caprocks with higher hard minerals, such as quartz, exhibit higher minimum fracture pressures. Additionally, positive interactions between siderite and feldspar intensify cementation within the pore structure. This study provides valuable insights into the mineralogical change effects on caprock integrity and offers a reliable framework for assessing caprock integrity during long-term CO2 storage.
Identification and In-Depth Investigation of External Casing Corrosion in an Exploration Well Prior to Field Development
Authors: Chikh Selma , Govil Amit
Published: March 2024

External corrosion in new casings on the Norwegian Continental Shelf (NCS) is rare. An exception to this was discovered when reentering an exploration well that had been temporarily plugged and abandoned for 2 years. A pressure test showed the 9 5/8-in. liner was leaking. A multidisciplinary investigation was done to find the precise depth of the leak and its root cause. The proper logging technologies were carefully selected for this purpose. Due to the relatively low leak rate, it was suspected that holes in the liner were small. To locate these holes, noise, temperature, ultrasonic high-resolution corrosion, and multifinger caliper logs were recorded. One of the hypotheses for the root cause of the leak was corrosion resulting from the corrosivity of the formation fluid combined with crossflow between the depleted formations. To test this, a water-flow log was run to find any potential crossflow behind the liner. Modular dynamic tester sampling was performed to extract formation water samples from the interval for chemical composition analysis.

The high-resolution corrosion data obtained from azimuthal and ultrasonic measurements showed the presence of multiple depths of external casing corrosion. These depths coincided with sections of the liner that were uncemented and therefore directly exposed to surrounding formation water. Analysis of the temperature data and the water-flow log during static well conditions enabled finding the precise location of the leak along with the detection of upwards water (or oxygen) movement behind the casing.

Additionally, a detailed examination of water samples taken from the 12 ¼-in. section of the sidetrack well revealed that the formation water had a low pH and a high CO2 content, which were considered significant for the context of the NCS. Based on these observations, the corrosion rate was estimated at about 4 mm/year. This conclusion relied on the confirmation of the formation water flow from the depleted formations.

This work helped to find the true root cause, which was found to be related to the selected well design, where the "overburden" was in communication with the reservoir section of a nearby field. As a preventive measure to avoid the recurrence of such issues in future similar wells in the NCS, the well design was changed during early field development.
Record-Setting Workover Saves Extended Marcellus Lateral
Authors: Lesnick C. W. , Kirk J. A. , Luckey E. , McClanahan D. J. , Saltel N. , Lian R. , Lim S.
Published: March 2024

An erroneous production string cement job often leaves an operator with a tough decision to make; the technical and economic feasibility of a successful intervention must be considered and compared to sidetracking or, at worst, abandonment. CNX Resources, collaborating with Thru Tubing Solutions (TTS) and SLB, was able to develop and execute a unique (and record-setting) workover to save a 19,381 ft lateral in the Marcellus shale.

An incorrect mixture of cement slurry left CNX Resources with 20,489 ft (of 27,510 ft MD) of 51/2-in 23ppf P110 production casing cemented off. A cement lead was pumped without issue. However, while pumping the cement tail and displacement, pressure gradually increased until it reached the pressure limitations of the rig equipment, resulting in a premature shut down. Utilizing a combination of traditional drilling and completions philosophy, a series of past lessons learned, and new-age technology, CNX, TTS, & SLB managed to clear the casing of nearly 20,500 ft of cement, perf and squeeze cement 6,019 ft into the lateral, and set the deepest (from KOP on US Land) casing patch ever set by SLB. This successful, more sustainable implementation offered upwards of 17% savings compared to the alternative.

Bottom Hole Assembly (BHA) selection, solids control, and fluid system management played a vital role in the cement drillout portion of the workover. Rates of penetration of up to 85 ft/hr were achieved and maintained throughout the job. In total, it took 19 days (approximately 17.5 days in hole) to drill the 20,489 ft of cement. Perforation depths were carefully determined at 14,130 ft via ultrasonic imaging and cement bond logging. Circulation was established and cement was squeezed to exceed state regulatory requirements. Due to the unique circumstance, a custom, fit-for-purpose expandable casing patch was designed and successfully installed to isolate the squeeze perforations while returning the casing to mechanical properties fit for fracturing operations. A casing integrity test to 10,500 psi was achieved post-installation of the casing patch.

This case study features the deepest 20,000+ ft drillout of cement for TTS (27,510 ft MD), a detailed look into a complicated extended lateral perforation and squeeze operation, as well as the deepest set (from KOP) casing patch for SLB on US Land (14,154 ft MD).
Milling the Unmillable: Design, Testing and Execution for Milling Non-Rotationally Locked Frac Sleeves
Authors: Burke J. , White M. , Schmohr A.
Published: March 2024

As drilling and completions operations continue to push the boundaries of extended lateral lengths and demand increases for higher stage density, technology is evolving, and new technologies are being developed to enable unlimited stage count. In the frac sleeve design space, one technology that has adapted to meet the increasing demand of these operations is unlimited sleeve systems. Unlimited frac sleeves allow sleeves to be preinstalled during the drilling phase and can be configured for uncemented and cemented completions. During subsequent multi-stage stimulation operations, darts are deployed from surface and rely on a range of methods (depending on the system) to count sleeves and activate to open only a specific sleeve or set of sleeves. All the sleeve profiles are uniform, so unlike graduated ball drop technology, sleeve ID remains constant regardless of the stage count (Davis et al. 2023) (Gibson, 2022). However, some unlimited sleeve designs feature an ID restriction relative to the nominal ID of the host casing. Even though the ID reduction is subtle and constant for all installed sleeves, this can limit future well intervention access for certain applications. In a few of these systems, once the sleeve shifts open and the well is stimulated, the restricted sleeve insert is no longer rotationally locked in place. In addition, some of the restricted sleeve inserts are constructed out of high strength chrome moly steel.

The mentioned design factors present a unique challenge when it comes to milling out to accommodate certain intervention needs. This paper outlines key steps that were taken to create a successful method for milling out restrictions that wouldn't have been possible using traditional equipment and techniques. This paper highlights the process in which a mill was designed, tested on surface, then tested downhole, and ultimately optimized through subsequent downhole runs. This led to the successful removal of a non-rotationally locked sleeve, clearing a pathway to allow a retrofit ﬂow control system to be installed.
ICD Completion Stimulation and Water Shutoff Using Inflatable Straddle Packers
Authors: Fajardo Sergio Rondon , Slama Hedi , Sunagatov Rustem , Badrawy Kareem
Published: March 2024

This study describes how the deployment and operation of an inflatable straddle packer combined with a real-time coiled tubing (CT) downhole measurement system improved the productivity of a well by optimizing an intervention that required selective treatment of multiple zones. The objective was to have the selected products reach only the targeted inflow control device (ICD) while isolating the other ones.

The inflatable, resettable, configurable, CT-conveyed straddle packer was set up to isolate a portion of the production ICD completion and allowed precise injection of stimulation and water conformance chemicals in one run. This system is more precise than other methods of selective placement (e.g., chemical diverters) and only requires a slight amount of tension and/or set-down weight to operate under its different configurations (inflation, spotting, and injection). Its combination with real-time downhole measurement capabilities enabled rapid response and adjustments to the actual downhole conditions throughout the operation.

The assembly was run successfully and managed to selectively stimulate and shut off two different zones in one trip, thus avoiding the use of multiple plugs to isolate the different sections. The real-time downhole measurement casing collar locator module permitted accurately placing the straddle section in front of the ICD port, while inflatable packers and a flow control module isolated mechanically the rest of the completion to facilitate fluid placement. Using the software specifically designed for this application, in combination with a memory logger tool that enabled a more accurate post-job evaluation, it was confirmed that all treatment fluids were injected into the targeted ICD zones, preventing more-permeable sections from absorbing it and adding the flexibility to avoid injecting the fluid used for the inflation of the packers.

This case study proposes an innovative approach to integrating CT conveyance, telemetry, and mechanical wellbore isolation tools to enhance production in wells with challenging configurations. While a thorough design identifies the optimized execution strategy, this methodology allows reducing the time of operation execution and using the treatment chemical fluids in a cost-effective manner.
From Zero to Hero: A New Breakthrough of Stimulation Method by Combining Acidizing and Cyclic Extended Breakdown in Sawah Field
Authors: Ilfi _ , Setiyawan Hanif , Masyhuri Ali , Rusli _ , Mileota Christian Eliezer , Ramadhan Iftikar Luthfi , Nugroho Rinenggo , Afton M
Published: March 2024

The Sawah field, a waterflood field, currently produces approximately 130,000 BFPD with an average 96% water-cut. The Fluid In Fluid Out (FIFO) stands at only 0.6, resulting in suboptimal waterflood performance. One cause of the low injection rate in Sawah field is injector plugging due to solid content and/or scale, and characteristics of the reservoir itself. Pressure Transient Analysis (PTA) further validates significant skin and permeability reduction.

To improve the injection rate, workover activities are conducted on the targeted well using a combination of the Acidizing and C-EBD (Cyclic Extended Breakdown) methods. This involves a chemical and mechanical effort, where the acid dissolves scale, and the C-EBD creates fractures. Compatibility tests are conducted between acid and water production, as well as acid and water injection. A 15% HCl simple acid is injected with a 3-feet penetration near the wellbore using coiled tubing. Following soaking, the treatment continues by injecting water into the reservoir in 6 cycles, with 350-700 bbls of water for each cycle.

During workover activities, improved injectivity was observed through Step Rate Tests (SRT). After acidizing, a rate of 2.5 bpm at 1,600 psi was achieved, followed by 3 bpm at 1,350 psi after the first 3 cycles of C-EBD. Further injectivity improvements occurred during subsequent C-EBD cycles, with the first 3 cycles reaching 2.4 bpm at 1,300 psi, and the next 3 cycles achieving 3.5 bpm at a similar pressure. Post Put on Injection (POI), the injection rate increased from 0-30 to 5,100-8,500 BWIPD, marking the well's highest injection rate in history. This notable success opens opportunity for Sawah Field, facilitating the reactivation of trade-off wells and increased capacity to handle additional fluids from size-up jobs or new wells. The collaborative efforts of the Subsurface, Research, and Workover Teams in the Sawah field were vital in achieving this remarkable result, contributing to longer injection well lifetimes, preventing overflow at surface facilities, and enhancing employee satisfaction.

A lesson learned emphasizes the need to verify flow meter readings before and during execution, facilitating the prompt identification of problems or areas for improvement. Additionally, conducting an extra Step Rate Test (SRT) before acidizing serves as an added baseline. This successful approach is currently being implemented in other injectors within the Sawah field facing similar plugging issues, showcasing its ongoing effectiveness in enhancing operational practices.
Rethinking Coiled Tubing String Lifespan Assessment: Leveraging Frequent Inspections for Enhanced Operational Insights
Authors: Rath B. , Watson B. , Glanville Joel
Published: March 2024

Traditionally, the industry benchmark for determining the lifespan of a coiled tubing string has relied on conventional parameters like running meters or fatigue analysis. This study will highlight the benefits of utilizing frequent coiled tubing string inspections as a key factor in assessing the effective remaining operational life of coiled tubing strings. The study aims to provide valuable insights that can enhance decision-making in asset management and maintenance procedures.

A sample of coiled tubing strings across various operational environments underwent inspections at key intervals during their respective operational lifespans. Rigorous inspection protocols were implemented, capturing data on factors like corrosion, material degradation, and stress-induced deformities. A comparative analysis was conducted using historical data obtained from running meters and fatigue analysis to highlight the unique insights provided by frequent inspections.

The findings of this study underscore the significance of frequent string inspections in assessing the operational lifespan of coiled tubing strings. While traditional methods such as running meters and fatigue analysis remain informative, they often overlook localized stressors and gradual deterioration that can compromise string integrity. In contrast, frequent inspections offer insights into the evolving condition of the strings, enabling timely interventions to prevent catastrophic failures. Furthermore, the data collected from frequent inspections can be utilized in an effective manner to anticipate future wear patterns and potential failure points. This proactive approach to maintenance and asset management enhances operational efficiency, reduces downtime, and optimizes resource allocation.

This study sheds light on a significant departure from the traditional industry practice of assessing the lifespan of a coiled tubing string through conventional means. Shifting the service industry's focus toward frequent inspections as a new perspective for assessing coiled tubing string lifespan holds positive implications for asset management and maintenance strategies. By embracing this approach, service companies can make more informed decisions about when to replace or repair coiled tubing strings, ultimately prolonging their service life and minimizing operational disruptions.
Complex Coiled Tubing Fishing Operation of Slickline Tools with No Kill Fluid in the Well in Danish North Sea
Authors: Kaul K. , Jari A. , Blanckaert T.
Published: March 2024

As part of offshore workover operations in the Danish North Sea to safeguard the future of producing oil wells, older completions are being changed to new 5 in Glass Reinforced Epoxy (GRE) lined completions using workover rigs. During one of the several phases of this operation in one of these wells, slickline (SL) was being used to remove scale using a bailer when the Bottom Hole Assembly (BHA) got stuck and lost in the well. The wire was pulled to 70% of its breaking strength of 2150 lb with no indication of the SL jar firing. The fish left in the wellbore was a 37 ft long tool consisting of a roller stem, spang jar, and a 3 in pump bailer assembly. The top fishing point was a 1.75 in fish neck rope socket, with the top of the fish at 7219 ft.

This horizontal oil producer was first drilled and completed in 2001 using a jack-up rig over a platform.

The job objective for Coiled Tubing (CT) was to return the well to the original workover plan by safely fishing the lost BHA while considering the following conditions:

The fishing tool combined with the fish would be too long for the available lubricator length. The hydrostatic pressure of the existing well fluid would be insufficient to overcome the reservoir pressure. A pressure-tested barrier is present between the casing and tubing annulus. The deep-set plug installed in the tubing at ~7350 ft has been pressure and inflow tested to 2900 psi.
The Role and Benefits of Intervention-Based Production in the Energy Transition and the Drive to Net Zero
Authors: Billingham M.
Published: March 2024

This work is an effort to quantify the CO2 production reduction with intervention-associated production. A brief summary of possible savings has been presented (Billingham et al. 2023). There is a global drive to reduce CO2 production to meet net zero ambitions and limit global warming. Fossil fuels, including oil and gas, have been shown to be a major contributor to CO2 emissions leading to an ongoing drive for energy transition to "greener" energy sources. Within this scenario, however, world energy demand continues to increase with a significant percentage of the world's population in a state of energy poverty. The growth of green-based new energy is significant but alone will not be able to meet the world's near-term energy requirements. As such, oil and gas will remain an important energy source in the near to mid-term future.

To maintain and increase production there are two avenues, these being the drilling of new wells or the reduction in the decline of production in existing fields, which ideally will include increases in recovery factors. The industry states that the latter approach delivers the cheapest production with the lowest carbon footprint. It makes sense that the improved utilization of existing infrastructure can deliver this, and the associated cost of production has been quantified before (Billingham et al. 2023). This work assesses intervention-associated production techniques to quantify the CO2 production reduction associated with this production.

Beginning with a high-level perspective evaluating rig-based new well production increases compared to agile interventions, the work then assessed specific technologies and methods that can deliver the desired outcomes. For example, it has been estimated that using a lightweight intervention vessel (LWIV) could reduce the associated CO2 production by 80% when compared to performing the same activity from a modular drilling unit (MODU). Opportunity for further improvements were also investigated.

Operators have the challenge of meeting global energy demand and their net-zero ambitions. Intervention-based production should be an enabler in achieving this balance. This work will serve as an industry reference as to the benefits of intervention-based production during the ongoing energy transition and why it should be a key focus.
Investigating the Impact of Hydrocarbon Solvent on In-Situ Asphaltene Precipitation in Solvent-Assisted Cyclic Steam Technique
Authors: Rahnema Hamed , ElMasry Aly , Rahnema Milad
Published: March 2024

Heavy oil recovery techniques often confront a significant challenge in in-situ asphaltene precipitation. This procedure significantly affects the characteristics of reservoirs and impedes optimal oil extraction. The purpose of this research was to examine how hydrocarbon solvents affect asphaltene precipitation occurring naturally in the reservoir as well as the resulting asphaltene content in processed oil. This was conducted using a laboratory-level dynamic model and the solvent-assisted cyclic steam stimulation (CSS) method. Throughout this experiment, which comprised six cycles, the steam-solvent blend’s pressure was consistently maintained close to 680 psi and the temperature was maintained at 500°F at the injection point. The findings revealed crude oil cracking at this temperature and noticeable in-situ asphaltene precipitation during the solvent-assisted CSS process. Notably, asphaltenes demonstrated mobility within porous media, contributing to their production in subsequent CSS cycles. Compared to a steam-only CSS control experiment, a higher asphaltene content in the original oil was observed, indicating that thermodynamic changes during the experiments likely caused asphaltene cracking. To sum up, this research provides an understanding of the effects of heavy oil recovery methods that rely on solvents on the precipitation of in-situ asphaltene and the content of asphaltene in the refined oil.
Designing a Data Mining-enabled Case-based System for Tuberculosis Diagnosis
Authors: Indebu Irandufa , Meshesha Million , Mohemmed Wesenu
Published: March 2024

Tuberculosis remains a persistent public health problem in Ethiopia, which demands innovative solutions for diagnosis and treatment support. Knowledge-based systems, particularly case-based systems, offer valuable decision-making assistance for various diseases. This paper introduces a data mining-driven approach for automatic knowledge extraction to develop a case-based system for tuberculosis diagnosis. Hidden insights are extracted from a tuberculosis dataset through the hybrid knowledge discovery process. The collected data set is pre-processed to fill in missing values, correct outliers, and remove noise. Clustering techniques, such as K-means, Make Density-based clustering, and farthest first, are employed to construct a descriptive model. The K-means algorithm is selected for its superior performance. Integration of the descriptive model into a case-based system is done using a Java-based integrator module. The prototype case-based system demonstrates an accuracy of 90%, which is a promising result. Further work is required to integrate the case-based system with rule-based towards developing a generic knowledge-based system.
Assessment of Soil Moisture during landslide over a hilly region: A Case Study
Authors: Fatima Hashmi , Sreevat Raghavendra , Mohandas Saji , Prasad V. S.
Published: March 2024

Landslides are one of the common geological hazards in the hilly regions throughout the world. Other than geological, morphological and anthropogenic causes, precipitation is the most common triggering factor for the occurrence of landslides. Rainfall-induced landslides are the result of the combined action of precipitation on topography, geology, soil and vegetation. Soil moisture and rainfall are intervened with each other. Forecasting landslides based on soil moisture is very difficult because mainly other geological and geomorphological parameters play quite a dominant role. However, in this study we analyse the soil moisture before and during landslides at three places (Solan, Shimla, Mandi) in Himachal Pradesh, India, which happened on 14 august 2023 after heavy rainfall. This study compares the various models, observations and reanalysis datasets available and assesses the various components of hydro-meteorological factors leading towards potential prediction of landslides. Model forecast is predicting an increase in soil moisture for the day when landslide occurred; therefore soil moisture forecast can be used in landslide early warning system.
Contextual analysis of cervical cancer prevention policies in Iran: A Leichter-based model
Authors: Pirani Narges , Akrami Forouzan , Jafari Mehdi , Pirani Hadis , safari Hossein , EbadiFardAzar Farbod , Doshmangir Leila
Published: March 2024

Background: Cervical cancer is considered the fourth most common type of cancer among women worldwide. The prevalence of this cancer is also increasing in Iran. This study aimed to conduct a context analysis of Iran's health policy concerning cervical cancer prevention.
Methods: In this qualitative study, data was collected through semi-structured interviews between July 2020 and September 2021. The sample consisted of 43 individuals, purposefully chosen to represent faculty members, researchers, policymakers, health insurance administrators, personnel of community health centers, and service users. The data underwent analysis using the framework analysis method, in accordance with the Leichter model, with the aid of MAXQDA2020 software.
Results: Due to the increasing incidence of cervical cancer and the growing international advocacy, a policy opportunity has arisen to focus policymakers' attention on preventing cervical cancer in Iran. The main challenges to implementing these policies are conflicts of interest, a poorly organized referral system, inadequate financial assistance for vulnerable groups, low public awareness, and inconsistent guidelines.
Conclusion: Overall, the findings highlight the need for comprehensive approaches to address cervical cancer in Iran. Such measures should emphasize elevating public awareness, encouraging human papillomavirus (HPV) vaccination, providing financial assistance for the cancer control plan, and supporting at-risk populations.
Analgesic Effectiveness of Wound Infiltration with Bupivacaine Versus a Mixture of Bupivacaine with Tramadol for Postoperative Pain Management Among Parturients Undergoing Elective Cesarean Section Under Spinal Anesthesia at Dilla University Referal Hospital, 2023: A Double-Blind Randomized Controlled Trial
Authors: Milkias Mesay , Mekonnen Semagn , Aweke Zemedu , Getachew Hailemariam , Mulugeta Hailemariam , Kebede Melkamu , Destaw Belete , Melese Medhanit , Ahmed Siraj
Published: March 2024

Background
Post-cesarean pain is among the principal problems with an incidence rate ranging from 25.5 to 80%. A variety of pain managing approaches have been used over the years, to manage post-cesarean pain, but none of them were free of adverse effects. Wound infiltration is a simple and feasible approach to managing post-cesarean pain. Despite its simplicity, the effectiveness of wound infiltration with a mixture of bupivacaine and tramadol is still unknown.
Objective
The study aims to compare the analgesic effectiveness of wound infiltration with bupivacaine versus a combination of bupivacaine with tramadol for postoperative pain management among parturients undergoing cesarean section under spinal anesthesia.
Methodology:
A double-blind, superiority-based, parallel, randomized controlled trial was conducted on 60 parturients. Parturients were randomized to take either bupivacaine (B = 30) or a combination of bupivacaine and tramadol (BT = 30). The homogeneity of variance was examined using Levine's test, and the normality was assessed using Shapiro-Wilk. The independent t-test and the Manny Whitney U test were used, respectively, for Parametric and non-parametric data. To assess the repeated measurements, a mixed linear model and general estimating equations were used. A p-value of below 0.05 is taken as Statistically significant.
Result
Totally 60 parturients were analyzed and no dropouts. The severity of pain in the 6th hour is 6 times greater in the B group in comparison to the BT Group (P = 0.001, OR = 6.289, CI = 2.097–18.858). The mean tramadol consumption was lesser in the BT group (140.00 ± 48.066 mg) than B group (175.00 ± 34.114 mg) min with a statistically significant mean difference of 10.761 (95% CI, 13.459 to 56.541), t (58) = 3.252, P = 0.002, (d = 0.839). The mean first analgesia request was higher in a mixture of tramadol and bupivacaine group, (Mean ± SD) (367.33 ± 50.099 min) than bupivacaine group (216.33 ± 68.744 min) with a statistically significant difference of 15.530 (95% CI, -182.087 to -119.913), t (58) = 5.6553, P = 0.001.
Conclusion and recommendation:
Wound infiltration with a combination of bupivacaine and tramadol is more effective than bupivacaine alone for postoperative analgesia for pregnant patients who underwent cesarean delivery under spinal anesthesia.
Demonstration of an energy-efficient Ising solver composed of Ovonic Threshold Switch (OTS)-based nano-oscillators (OTSNOs)
Authors: Lee Young Woong , Kim Seon Jeong , Kim Jaewook , Kim Sangheon , Park Jongkil , Jeong YeonJoo , Kim Jaewook , Hwang Gyu Weon , Park Seongsik , Park Bae Ho , Lee Suyoun
Published: March 2024

As there is an increasing need for an efficient solver of combinatorial optimization problems, much interest is paid to the Ising machine, which is a novel physics-driven computing system composed of coupled oscillators mimicking the dynamics of the system of coupled electronic spins. In this work, we propose an energy-efficient nano-oscillator, called OTSNO, which is composed of an Ovonic Threshold Switch (OTS) and an electrical resistor. We demonstrate that the OTSNO shows the synchronization behavior, an essential property for the realization of an Ising machine. Furthermore, we have discovered that the capacitive coupling is advantageous over the resistive coupling for the hardware implementation of an Ising solver by providing a larger margin of the variations of components. Finally, we implement an Ising machine composed of capacitively-coupled OTSNOs to demonstrate that the solution to a 14-node MaxCut problem can be obtained in 40 ms while consuming no more than 2.3 mJ of energy. Compared to a previous hardware implementation of the phase-transition nano-oscillator (PTNO)-based Ising machine, the OTSNO-based Ising machine in this work shows the performance of the increased speed by more than one order while consuming less energy by about an order.
Exposure to gestational diabetes mellitus in utero impacts hippocampal functional connectivity in response to food cues in children
Authors: Kullmann Stephanie , Zhao Sixiu , Semeia Lorenzo , Veit Ralf , Luo Shan , Angelo Brendan , Chow Ting , Birkenfeld Andreas , Preissl Hubert , Xiang Anny , Page Kathleen
Published: March 2024

Objectives
Intrauterine exposure to gestational diabetes mellitus (GDM) increases the risk of obesity in the offspring, but little is known about the underlying neural mechanisms. The hippocampus is crucial for food intake regulation and is vulnerable to the effects of obesity. The purpose of the study was to investigate whether GDM exposure affects hippocampal functional connectivity during exposure to food cues using functional magnetic resonance imaging.
Methods
Participants were 90 children age 7–11 years (53 females) who underwent an fMRI-based visual food cue task in the fasted state. Hippocampal functional connectivity (FC) was examined using generalized psychophysiological interaction in response to high-calorie food versus non-food cues. Food-cue induced hippocampal FC was compared between children with and without GDM exposure, while controlling for possible confounding effects of age, sex and waist-to-hip ratio.
Results
Children with GDM exposure exhibited stronger hippocampal FC to the insula and striatum (i.e., putamen, pallidum and nucleus accumbens) compared to unexposed children, while viewing high caloric food cues.
Conclusions
Intrauterine exposure to GDM was associated with higher food-cue induced hippocampal FC to reward processing regions. Future studies with longitudinal measurements are needed to clarify whether increased hippocampal FC to reward processing regions may raise the risk of the development of metabolic diseases later in life.
Genomic-transcriptomic analysis reveals Syrian hamster as a superior human disease animal model
Authors: Wang Yaohe , Wang Chuchu , Cheng Zhenguo , Miao Jinxin , Xue Xia , Dong Yunshu , Zhao Li , Guo Haoran , Wang Jianyao , Wang Zhizhong , Lu Shuangshuang , Zhang Zhongxian , Gao Dongling , Wang Zhimin , Wang Pengju , Fang Guangming , Peng Ying , Zhai Yafei , Zhang Lirong , Dunmall Louisa , Wang Jun , Tang Wenxue , Li Xiaowei , Ding Zhongren , Zhao Xiaoyan , Li Ling , Lemoine Nicholas , Tang Wenjie , Tonge Daniel , Wang Zhongde , Dong Jianzeng
Published: March 2024

Backgroud: The Syrian hamster (Mesocricetus auratus) has shown promise as a human diseases model, recapitulating features of different human diseases including the emerging COVID-19. However, the landscape of its genome and transcriptome has not been systematically dissected, restricting its potential applications.
Results: Here we provide a complete analysis of the genome and transcriptome of the Syrian hamster and found that its lineage diverged from that of the Chinese hamster (Cricetulus griseus) around 29.4 million years ago. 21,387 protein-coding genes were identified, with 90.03% of the 2.56G base pair sequence being anchored to 22 chromosomes. The further comparison of the transcriptomes from 15 tissues of the Syrian hamster disclosed that Syrian hamster shares a pattern of alternative splicing modes more similar to humans, compared to rats and mice. A integrated genomic-transcriptomic analysis revealed that Syrian hamster also has genetic and biological advantages as a superior animal model for cardiovascular diseases. Strikingly, several genes involved in SARS-COV-2 infection including ACE2present a higher homology with humans than other rodents and show the same function as the human counterparts.
Conclusion: The detailed molecular characterisation of the Syrian hamster in the present study opens a wealth of fundamental resources from this small rodent for future research into human disease pathology and treatment.
Nicotinic acid suppresses liver cancer metastasis via histone lysine nicotinylation
Authors: Zhang Hong-Quan , Jiang Yuhan , Li Yixiao , Zhang Lei , Yan Haoyi , Qin Ziheng , Li Qianchen , Peng Yidi , Liu Jia , Weng Yejing , Cheng Zhongyi , Lv Danyu , Zhang Jing , Tang Yan , Zhan Jun
Published: March 2024

Vitamin B3 is the major precursor of NAD+ and NADP+, however it was unknown whether this vitamin supplementation could modify histone epigenetically. Here, we report nicotinic acid (NA), a component of vitamin B3, suppresses liver cancer metastasis specifically, via stimulating histone lysine nicotinylation (Knic). Importantly, nicotinyl-CoA, that metabolically generated by NA via ACSS2, stimulates histone Knic in vivo and in vitro. Histone Knic regulates chromatin accessibility and inhibits binding of transcription factor HOXB9 to the promoter of oncogene PPFIA1, resulting in inhibition of hepatocyte carcinoma progression. Notably, we found that NA specific induces histone Knic and suppresses hepatocyte carcinoma progression, whereas nicotinamide, an amide form of nicotinic acid, does not stimulate nicotinylation, instead promotes tumour growth and metastasis. These findings suggest that vitamin B3 supplementation may contribute to cancer progression depending on its composition. Collectively, we demonstrated that histone lysine nicotinylation is a histone mark controlling gene expression and NA supresses liver cancer progression by inducing histone lysine nicotinylation.
Design and synthesis of Diphenyl-1H-imidazole analogs targeting MPro/3CLpro enzyme of SARS-CoV-2
Authors: Vora Amisha , Kanhed Ashish , Thakkar Ami , Gudepalya Rudramurthy Renukaiah , Shandil Radhakrishnan , Yogi Maddipatla , Harisha Rajappa , Singh Mayas , Narayanan Shridhar
Published: March 2024

The prevailing COVID-19 pandemic, triggered by the novel coronavirus SARS-CoV-2, stands as the predominant global health crisis of the decade, claiming millions of lives and causing profound disruptions to society. Despite the rapid development of vaccines against COVID-19, the situation remains challenging, necessitating the exploration of new antiviral drugs. In this study, we present the design and synthesis of Diphenyl-1H-imidazole derivatives as a potential lead series for inhibiting the SARS-CoV-2 3CLpro enzyme. The synthesized molecules underwent screening for inhibiting the SARS-CoV-2 3CLpro enzyme at a concentration of 20µM. Compounds 6-14 exhibited inhibition ranging from 88% to 99%. Further assessments were conducted to evaluate the anti-SARS-CoV-2 activity of these compounds against both the ancestral Wuhan strain and the Delta variant in virus-infected cells. Compounds such as 4-(4-chlorophenyl)-2-(3,4-dimethoxyphenyl)-1H-imidazole (9), 4-(2,4-dichlorophenyl)-2-(3,4-dimethoxyphenyl)-1H-imidazole (10), and 4-(4-(2,4-dichlorophenyl)-1H-imidazol-2-yl)benzene-1,2-diol (14)exhibited promising activity against both the Wuhan strain (with IC50 values of 7.7 µM, 12.6 µM, and 11.8 µM, respectively) and the Delta variant (with IC50 values of 7.4 µM, 13.8 µM, and 12.1 µM, respectively). Moreover, the 3CLpro inhibition IC50 values for these compounds correlated well with the observed antiviral activity, measuring at 5.1 µM (9), 10.9 µM (10), and 7.3 µM (14). These findings underscore the efficacy of diphenyl-1H-imidazole derivatives as promising candidates for further development and optimization in the fight against COVID-19.
Successful Pregnancy in a Patient with IgA Nephropathy Treated with Telitacicept: A Case Report and Literature Review
Authors: Du Xinru , Lu Xuehong
Published: March 2024

IgA nephropathy (IgAN) is the most common cause of primary glomerulonephritis, with complex pathogenic mechanisms involving abnormal B cell activation. As a novel biologic agent, Telitacicept inhibits both B-lymphocyte stimulator and a proliferation-inducing ligand, can reduce B cell-mediated autoimmune responses, suppressing the production of galactose-deficient IgA1 and thereby inducing disease remission. Women with IgAN are at a higher risk of adverse pregnancy outcomes such as preeclampsia and miscarriage, especially those with uncontrolled massive proteinuria and advanced chronic kidney disease. Therefore, IgAN disease control before and during pregnancy is essential. We report the case of a female patient who was effectively treated with Telitacicept and subsequently successfully conceived. This case report also reviews the characteristics and outcomes of pregnancy in patients with IgAN and explores the value of Telitacicept in women of childbearing age, suggesting effective and safe treatment options for women who wish to conceive.