bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating the Effect of Capillary Pressure on DFIT and DFIT-FBA Analysis
Authors: Haqparast S. , Zeinabady D. , Clarkson C. R.
Published: March 2024

The diagnostic fracture injection test (DFIT), and the new variation DFIT-FBA (FBA = flowback analysis), are well-testing methods performed before the main hydraulic fracturing operations to obtain several key parameters used in hydraulic fracture design and for reservoir simulation input. The classic (conventional) DFIT includes the sequence of pump-in, followed by a long shut-in (hours to days), while DFIT-FBA utilizes the sequence of pump-in, followed by a brief (minutes) shut-in, and then flowback to accelerate the time to reach closure and obtain reservoir pressure. While DFITs are still widely implemented, DFIT-FBA has the advantage that key properties can be derived in a matter of 2-3 hours versus (typically) more than a day for a conventional DFIT.

The current models used to estimate reservoir parameters from DFIT and DFIT-FBA require calculating the fracturing fluid leakoff volume into the reservoir. While mechanisms affecting leakoff include viscous, capillary, and osmotic forces, current DFIT models only consider viscous forces. While the effect of the capillary pressure on fluid leakoff has been explored and confirmed by multiple researchers, it has not been incorporated into models and software for hydraulic fracture modelling or DFIT/DFIT-FBA analysis.

An important question addressed in this work is whether the capillary pressure effect is significant over the short timeframe of the DFIT/DFIT-FBA test. Simulation results generated herein demonstrate that capillary pressure plays a significant role in the leakoff of hydraulic fracturing fluid into the reservoir during DFIT/DFIT-FBA tests; therefore, neglecting the effect of capillary pressure in the analyses can lead to substantial errors in reservoir parameter determination. Numerical simulation results also demonstrate that the presence of capillary forces accelerates leakoff and consequently the time of closure. For a simulated DFIT-FBA executed in an unconventional gas reservoir, approximately 25% of the total leakoff volume is attributable to capillary forces. Ignoring the effect of capillary pressure results in ~77% overestimation of reservoir permeability. Similarly, for a simulated DFIT case, this contribution is up to 26.5%, leading to ~77% overestimation of reservoir permeability. A sensitivity analysis performed herein underscores the significance of considering interfacial tension and contact angle, while reservoir permeability has a relative influence on the outcomes. Consequently, the early-time leakoff permeability estimated from DFIT/DFIT-FBA tests with current models is more precise for situations where there is reduced interfacial tension between the rock and fracturing fluid, and/or when the rock demonstrates mixed wettability.
Quantification of Gas Exsolution Dynamics for CO2/CH4-Heavy Oil Systems with Population Balance Equations
Authors: Dong Xiaomeng , Zhao Zulong , Yang Daoyong , Jia Na
Published: March 2024

Although foamy oil phenomenon has been considered as the key factor that dominates heavy oil recovery, the existing models cannot be used to accurately quantify gas exsolution dynamics in foamy oil under various conditions due to the inherent physics and complex flow behaviour. In this study, experimental and theoretical techniques have been developed to quantify gas exsolution dynamics of CO2/CH4-heavy oil systems while considering gas bubble nucleation mobilization, and binary coalescence. Experimentally, constant composition expansion (CCE) tests were performed with a sealed PVT apparatus for the CO2/CH4-heavy oil systems to induce foamy oil behaviour by gradually depleting pressure at a constant temperature, during which the pressures and volume changes were monitored and recorded continuously. Theoretically, the Fick's law, equation of state, classical nucleation theory, and population balance equation have been integrated to describe the gas exsolution dynamics, during which gas bubbles are discretized with the fixed-pivot technique. The gas bubble number and size distribution in the induced foamy oil can then be determined once the deviations between the measured and calculated parameters, including liquid volume and pseudo-bubble point pressure, have been minimized with the genetic algorithm. For both CO2- and CH4-heavy oil systems, not only can a reducing pressure depletion rate or an increasing temperature result in a higher pseudo-bubblepoint pressure, but also gas bubble growth is strongly dependent on both temperature and diffusion of a gas component in heavy oil, while increasing the solvent concentration in the heavy oil tends to hinder the gas bubble nucleation and mitigation due to the higher pressure set for the experiments. During the generation of foamy oil, a higher temperature reduces heavy oil viscosity to accelerate the diffusion process, positively contributing to the gas bubble nucleation, binary coalescence, and bubble mobilization, respectively. Compared with CO2, CH4 induces a stronger and more stable foamy oil, illustrating that, at a lower temperature, foamy oil is more stable with more dispersed gas bubbles. In this study, the newly developed theoretical techniques are able to reproduce gas exsolution dynamics at the bubble level, allowing us to seamlessly integrate them with any reservoir simulators to not only accurately characterize foamy oil behaviour, but also evaluate the associated recovery performance.
A Quick Decline Method for Forecasting Multiple Wells Using Sparse Functional Principal Component Analysis
Authors: Hamdi H , Zirbes E , Clarkson C. R
Published: March 2024

Accurate production forecasting for multiple wells that have both sparse and irregular measurements concurrently is a challenging task. Type-well analysis is commonly employed to model the average decline behavior of a group of wells from empirical relationships. The modeled type-well represents the behavior of a typical well in the studied reservoir. However, modifying the type-well to forecast individual well data is difficult. In this study, sparse functional principal component analysis (FPCA) is utilized to accurately forecast production from multiple wells simultaneously from the systematic statistical trends inferred from the group of wells.

Sparse FPCA analyzes an ensemble of irregularly-sampled timeseries to describe the underlying random process (RP) using the decomposed components. As such, one can sample from the estimated RP and generate a smooth and regularly-sampled timeseries. The sparse FPCA is primarily an interpolation method where the reconstructed timeseries could not reach beyond the horizon set by the ensemble length. However, with the proposed approach in this study, the decomposed components of FPCA are extrapolated using an autoregressive integrated moving average (ARIMA) model to generate the full probabilistic forecasts beyond the horizon. In this proposed method, the underlying RP is extrapolated first, and then the extended timeseries are generated simultaneously by sampling from the new RP. To validate the accuracy of the extrapolated data in the short-term, part of the timeseries with longer histories are excluded from the training process and only used for testing.

The sparse FPCA was applied to analyze monthly gas production data from 200 multi-fractured horizontal wells (MFHWs) of a selected operator in the Montney Formation in Canada. The results indicate that the production data of all the wells could be easily condensed using only two principal components, describing more than 99% of the information content of the production timeseries. Additionally, the resulting decomposed components were convoluted, and the production profiles of the wells with short histories were extended from the information contents of the ensemble. Additionally, with the proposed stochastic ARIMA technique, the production profiles of all the wells were forecasted for 400 months beyond the ensemble limit. The results demonstrate that the extrapolation could accurately match the measured data used for testing, which provides confidence in the stochastic long-term forecast.

This study demonstrates for the first time that sparse FPCA can be combined with the ARIMA model to quickly conduct the probabilistic production forecast for hundreds and even thousands of MFHWs simultaneously, which can significantly improve the current type-well modeling workflows.
Digital Solution for Coiled Tubing Pipe Pull Test Automation and Placement Optimization
Authors: Fonseca S. Hassig , Armstrong B. , Fossati L. , Brouwer W.
Published: March 2024

A new coiled tubing (CT) pipe pull test placement optimizer and automation solution is developed and integrated into an autonomous CT unit. This method provides consistency in strategic and automated pull test placement to extend the life of the pipe and consequently reduce total cost of ownership and greenhouse (GHG) emissions. A case study in the North Sea showcases the solution in real-time operations and simulated cases demonstrate the potential impact.

Pull tests are a common means of mitigating stuck pipe in CT operations. Traditionally, they are executed at fixed intervals while the CT is run in hole. Risks associated with this rote approach include repeated pull tests at an already fatigued section, which accelerates fatigue of the CT pipe, and pull tests executed in wellbore sections with completion restrictions. The new solution addresses those risks by systematically combining the pipe's fatigue profile, weld points, and completion information to strategically adjust the pull test schedule, reducing the impact of those tests on pipe fatigue and the risks associated with drifting across downhole completion jewelry.

The pull test automation and optimization are integrated into an automation-enabled CT unit in the North Sea. The automation eliminates the human factor and the risk of repeating pull tests at the same locations on each run; it also minimizes pull tests at the weakest points, which include the weld points where cycle fatigue is accelerated, and it eliminates pull tests at restrictions, reducing the risk of abrading or damaging completion jewelry. Finally, besides standardizing pull test placement, the combination of the pull test optimization and automation frees the CT operator to focus on other critical elements of the operation such as running and monitoring the unit and downhole tools, managing the crew, and engaging the customer representative.

The performance of the pull test automation and optimization solution is tested in a simulated environment to quantify the impact on the CT pipe from new (0% fatigue) to end of life (EOL, 100% fatigue). The simulation uses a CT pipe with 1 3/4-in. outer diameter (OD) and a mission profile from a previous intervention campaign. CT of this OD is common in CT operations worldwide, making it an interesting test subject for the analysis. As compared to the traditional pull test approach, the optimized pull test placement redistributes the fatigue to less-fatigued sections of the pipe and extends the useful life of the pipe from 137 runs to EOL to 176 runs to EOL. Extending the useful life by 28% is equivalent to reducing the pipe's run-on-run cost and GHG manufacturing emission contributions by 22%.
Successful Intervention in U and W Shaped Wells in Eagleford Basin – A Case History
Authors: Unnikrishnan Vikram , Navin Guruswami
Published: March 2024

An operator in Eagleford basin, decided to optimize production, by minimizing drilling efforts. This led to two wells drilled in a distinctive "U" and "W" shape, which would result in equivalent treatable laterals lengths in a lease with tight boundaries.

Plug and Perf stimulation technique was carried out in these two wells and post stimulation cleanout had to be performed. Intervention in these unique shaped wells need to be planned with the proper Bottomhole Assembly (BHA) configurations to ensure that that no misrun occurs. Though these wells are drilled successfully with the rig, since there is rotational and axial capabilities, it does not necessarily mean that a Coiled Tubing (CT) intervention would be less challenging. The frac plugs for isolation were set not just in the straight sections of the well but also in some part of the bend as well.

This paper will highlight the operational planning that was involved prior to performing intervention in these two wells. A complete coiled tubing modelling along with bending analysis on the milling BHA was performed to ensure that the downhole assembly does not undergo any failures due to well profile.

A total of 32 frac plugs in "W" shaped well and 38 frac plugs in "U" shaped well were successfully cleaned/milled out. The two wells were completed with 5 ½", 23 lb/ft casing with a Measured Depth (MD) of 17,846 ft and 21,064 ft respectively. A 4 ½" Tricone bit along with a 3 1/8" workover motor and extended reach tool was utilized for the operation.

Due to the pre-planning performed during the BHA selection, it eliminated a second run in each well, thereby allowing the operator to save around $150,000 on intervention costs. This paper will act as a guideline for any future intervention planned in wells with unique geometry.
Unique Electric Line Deployed Mechanical Cutting, Milling and Pulling Solution Successfully Applied in a Complex Fishing Operation, Regaining Access to a Critical Well
Authors: Murchie Stuart William , Magnussen Odd Einar , Finnesand Tore , Andersen Kristian , Gaballa Peter
Published: March 2024

An offshore injection well in an operating field situated in the Norwegian Continental Shelf was being used for secure dumping of old drill water and well debris, this being a critical resource in support of field operations. During a routine check of the functionality of the well's downhole safety valve (DHSV) it failed its seal test. A flow tube exercise tool was run to try and resolve the situation, however it proceeded to get stuck within the DHSV, preventing the valve functionality, blocking access to the well and hence rendering the well unusable until a solution was found.

The customer utilised all usual means to fish the exercise tool, with numerous slickline and e-line runs to jar and pull the fish proving unsuccessful. An assortment of high strength fishing tools were also used, including a high strength stroker providing as high as 100 Klbs force. This too was unsuccessful, proving brute force was not the solution. A detailed analysis of the situation was carried out to determine the probable cause, the extent of the challenges faced, and the appropriate solution options available. A thorough recovery plan was then devised based on a number of key steps and processes to be executed, with a decision tree created to aid operational progress. Steps included a means of determining the exact position of the core of the exercise tool. Bespoke tooling was also designed and tested to provide the securing, cutting and milling of several internal components of the exercise tool to enable it to be pulled free from the valve.

These e-line deployed solutions were highly innovative, providing extremely effective, precise, and controlled capabilities resulting in the flow tube exercise tool retrieval, in turn enabling further intervention operations and a subsequent re-completion to be carried out. As a result of the processes and solutions devised to recover the stuck exercise tool from this well, a new method for securely exercising DHSV flow tubes using strokers has been devised and applied as an alternate method by the operator.
Development and Initial Trials of Thermally Processed 95-Ksi Coiled Tubing
Authors: Elliott K. , Molero N. , Srinivasan H. , Arriaga E. , Al Qatari F. , Alsheheri M.
Published: March 2024

With a significant number of exploration and production programs pushing intervention boundaries, 95-ksi grade quenched and tempered (Q&T) coiled tubing (CT) has begun to be utilized in high-profile sour environments. This paper details the development of the newest 95-ksi grade of (Q&T) CT, specifically designed for increased fatigue life of existing products with performance in sour environments.

The authorship team is comprised of a multidisciplinary group within the CT business, including manufacturers, service companies, and the operator. Each stakeholder has different expectations regarding this development, but the main outputs of the program need to be (1) a repeatably manufacturable grade with (2) improved fatigue life and (3) resistance to catastrophic failure due to exposure to sour environments. This study describes the design control process that accounts for the concerns of all stakeholders.

The present review covers the initial development activity of identifying an alloy to make 95-ksi grade tubing. The process examined improvements to low cycle fatigue life and sour performance over 90-grade non-Q&T CT. Laboratory test results of 95-grade Q&T tubing are presented in this work. The low cycle fatigue testing comprises tests both with and without sour exposure. The testing without sour exposure is useful for providing comparative information to show how this grade can have an increased service life compared to 90-grade conventionally produced CT. The testing with sour exposure can be compared to the testing without exposure to show that low cycle fatigue life can be successfully modeled despite even in sour environments. The testing presents an examination of bias welds testing in low cycle fatigue as bias welds are considered a sensitive location for CT failure.

In the present decade, CT intervention requirements combining deeper extended reach horizontal sections and high-pressure cycling in sour environments are becoming more frequent, driving operators, service companies, and manufacturers to jointly pursue technologies and engineered solutions for safe and effective CT work. The study presented here paves the road for implementation of a value Q&T offering for such challenging environment.
Compression-Tolerant Mechanical Tubing Cutter with High Expansion Ratio and Real-Time Surface Readout
Authors: Cygan A. Z. , Osmond T. M. , Billingham M. E.
Published: March 2024

Mechanical pipe cutters are an increasingly attractive option for intervention and plug and abandonment (P&A) campaigns due to their simplicity, ease of deployment, and reduced risk of stored energy inherent in traditional energized pipe cutters. Limitations of current mechanical cutter designs include small expansion ratios, challenges to cut pipe under compressive load, and limited surface readouts that require expertise to interpret. A mechanical tubing cutter has been developed that seeks to address these challenges and limitations.

The robust mechanical design in the new cutter features a high expansion ratio with the ability to cut in tension, neutral weight, or compression, including multiple cuts per descent. Critical surface readouts have been incorporated to provide a fuller understanding of the cut and well response. Fully automated cutting algorithms, which minimize user interaction, have been programmed into the service to provide an active, torque-controlled cut that optimizes penetration and delivers consistency in performance. The cutter is designed as a modular addition to a full intervention solution family to offer combinable, multiobjective descents with a light wellsite footprint.

This new cutter has been deployed successfully by several operators to enhance well production and to successfully execute P&A scopes where other solutions were unfavorable or financially untenable. Two case studies illustrate the application of features such as the downhole sensors, automated algorithms, and expansion ratio and show how these features are central to achieving a successful cut.

This tubing cutter design expands the utility of mechanical cutters to target pipe that was previously inaccessible due to restrictions or unforeseen tubing deformation. In addition, the cutter reduces the risk of cutting complications stemming from compressive and torsional forces acting on downhole targets. Downhole automation enhances cutting reliability through reactive torque control, programmed stall recovery, and real-time response to changes in cutting conditions.
Autonomous Restriction Navigation Through Wellbore in Wireline and Slickline Operations
Authors: DiPasquale S. , Meirkhan J.
Published: March 2024

A novel technique of autonomous restriction navigation that significantly increases efficiency and safety is presented. New algorithms orchestrate the automated winch control system to prevent over-speeding when passing through restrictions, which diminishes incidents of unintentional pull-off and toolstring damage caused by entering wellbore obstructions at high speed. Every pull-off incident would significantly reduce the production of the well because the toolstring and cable must be recovered. This new dynamic speed scheduling system optimizes restriction navigation, showing an order of magnitude improvement over industry-standard human-driven winch operation.

A new forward-looking algorithm analyzes restrictions in the direction of conveyance to predict the time and distance to future encounters with restrictions. It uses toolstring length, current depth, cable speed, and the winch controller's deceleration rate to maintain the maximum allowed speed until the exact moment deceleration must occur for the toolstring to enter a restriction at the proper speed. Finally, it maintains a higher winch gear even at low speeds when passing through restrictions except in those situations when extra-low speed is required.

The new technique has been extensively tested in intervention campaigns in the North Sea, allowing comparison against manual operation and previous-generation automated conveyance. Winch operators would often fail to slow down at restrictions or would slow down too early or too late. Previous-generation automation, due to its lack of forward-looking algorithms, would not decelerate until the toolstring encountered the restriction and could accelerate with the toolstring still in the restriction. To prevent this, the wellsite supervisor would need to spend extra time manually calculating top and bottom restriction depths for each conveyance direction, often leading to overestimation or miscalculation of the restriction declarations. In case studies from field trials, the new technique consistently uses the correct restriction speed for the entire toolstring length. Users only need to declare wellbore speed restrictions as they appear on the well diagram. In manual operation, an experienced user will retain high winch gear through a restriction, whereas previous automation would stop and change gear. The new technique digitalizes winch driving competency by incorporating high-gear retention. After a year of field trials with zero incidents, several case studies with multiple restrictions in the well confirm the greater efficiency of the new navigation technique over previous generations.

The developed comprehensive automated speed-control logic and restriction navigation technique maximizes conveyance speed while eliminating risk and costly errors. Its intrinsic value increases when operations are performed in highly sophisticated well completions and tortuous wells, which are becoming more common.
Improving Well Completion Efficiency Though the Implementation of Jointed Pipe Injector Technology
Authors: Richard A. , Miller H. , Herrmann J.
Published: March 2024

Objectives/Scope

Currently, jointed pipe completions on live wells are performed by either a workover rig with a rig assist snubbing jack or a stand-alone snubbing jack. These technologies require extensive training and operator input to convey tubing in and out of the wellbore. Conventional snubbing jacks run the risk of losing control of the string when they are transferring load between travelling and stationary slips. The main objective of the Jointed Pipe Injector Technology is to provide a safer alternative by reducing operator input and reducing the risk of losing control of the string while reducing the time it takes to move tubular strings in and out of the wellbore under pressure.

Methods, Procedures, Process

Applying a jointed pipe injector into the well completions package where a typical jack would function removes the transfer of load because it maintains constant grip on the tubing, much like a coiled tubing injector. By integrating additional sensors into this package make-up and break-out procedures may be carried out remotely, further reducing operator intervention for remedial operations.

Results, Observations, Conclusions

Through the recent deployment of a rig-assist jointed pipe injector in the DJ Basin, the oilfield service companies have been able to reduce operator training time from months to weeks. Operator input has been reduced by over 94% compared to a conventional rig assist snubbing unit. Tubulars can be tripped in or out of the well at twice the speed of the conventional rig assist jack. The main injector control has been located remotely, reducing the number of personnel at risk on the work floor by 33%.

Novel/Additive Information

The deployment of the jointed pipe injector in well completion applications leads to levels of automation, control, and mechanization typically seen in modern drilling packages.
RBF Network Dynamic Sliding Mode Robust Control for Overhead Cranes with Uncertain Parameters
Authors: li shihua , Gao YouShan , Lv Shi-Ning , Wang Ai-Hong , Wan Yu-Fan
Published: March 2024

For the load swing and trolley tracking and positioning issues of overhead crane system during lifting operations with uncertain inherent parameters and partial unknown parameters, a dynamic sliding mode robust control algorithm based on RBF neural network is suggested. The Lyapunov stability of the closed loop error is Theoretically testified by the control algorithm .The control algorithm takes the sliding mode control idea as its structural framework. The design of the sliding mode surface takes into account the impact of the alteration in the control output, makes the sliding mode switching term adaptive by setting fuzzy rules ,and further derives the self adaption laws of the RBF neural networks to adapt the intricated as well as unknown dynamic parts in the system of overhead crane, rendering the operation of the system of overhead crane with no need for any system parameters as the signal input. For the sake of testifying the superior control accuracy under the influence of this tactics, a comparison was made with the layered sliding mode control method, with results demonstrated that the output power of the controller based on above algorithm designed in this paper proves more stable, and there is no long-term high-frequency jitter, while its anti-swing control effect on the load is also standing a better robust performance of any other controllers. It is also exceedingly significant to point out that when the system parameters change to some extent. While the trolley based on this control system can also achieve stable tracking and positioning under zero overshoot.
Cataract Risk Factors Prediction Using Deep Leaning Models
Authors: Saju Binju , R Rajesh
Published: March 2024

Cataracts are diseases that occur due to the existence of protein in the lens that develops an abnormal clumsy region in the eye. This can be avoided when it is recognized and identified in the beginning stages. Recently, data mining techniques have been utilized in classifying the stages of cataracts. This work proposes the risk factors for cataracts and classifies the cataract risk using deep learning models. The data was collected from patients who were diagnosed with cataracts. The proposed method is divided into two stages: pre-processing and classification. Hence, in the initial stage, the dataset is pre-processed by missing values, and the string values are converted into numeric values. Then, for risk prediction, a fuzzy rule-based clinical system is described. This is carried out by collecting information, accessing the risk factors, & creating knowledge from the patient’s clinical info. Then, in the second phase, there is classification-based stage advancement. The Fuzzified output is given to the classifier for classifying the stage advancement. The classifiers like ICNN (Improved Convolutional neural network + Arithmetic Optimization Algorithm), CNN (Convolutional neural network), DNN (Deep neural network), DBN (Deep Belief Network), RNN (Recurrent Neural Network), and GAN (Generative Adversarial Network) are used to classify the classes as Stage advancements category 1 (very fast stage advancement), category 2 (Moderate stage advancement), and category 3 (slow stage advancement-No Change in stage) are determined. The overall implementation is carried out on the MATLAB platform, and experimental results are compared across several deep learning (DL) models.
Intravenous methadone in perioperative acute and chronic pain management in Chinese adult cardiac surgical patients: a protocol for pilot randomised controlled trial
Authors: WONG Henry Man Kin , Wong Wai Tat , Liu XiaoDong , Li Ara Cheuk Yin , Au Sylvia Siu Wah , WONG Randolph Hung Leung
Published: March 2024

Background
Postoperative pain is significant in cardiac surgical patients. Perioperative analgesia with intermittent administration of opioids can result in significant fluctuations in serum opioid concentrations. Methadone should provide a rapid onset and long-term pain relief upon a single intravenous dose at induction of anaesthesia, and may reduce chronic postsurgical pain (CPSP) in cardiac surgical patients. The feasibility of using intravenous methadone in Chinese cardiac surgical patients, and its effect on acute and chronic pain management after cardiac surgery will be evaluated.
Methods
A single-centre, prospective, randomized-controlled pilot study. Adult cardiac surgical patients will be randomized to receive either methadone 0.2mg/kg (maximum dose 20mg) or equipotent dose of morphine at induction of anaesthesia. Patient-controlled analgesia morphine protocol, oral paracetamol and dihydrocodeine will be given for postoperative analgesia. Venous blood sampling for plasma methadone concentration will be obtained at regular intervals from study drug infusion to 96 hours after administration. The primary outcomes will be the recruitment and attrition rate, complications from methadone, and the perceived trial feasibility. Secondary outcomes include time weaned to spontaneous breathing trial, morphine consumption within 24 hours and 72 hours after surgery, time to first morphine rescue, postoperative pain score, patient satisfaction, length of stay in ICU and hospital. Side effects of opioids including sedation, nausea and vomiting, and time to first bowel opening will be recorded. CPSP will be assessed with Neuropathic Pain Scale and Pain Catastrophizing Scale at 3 and 6 months after surgery.
Discussion
There have not been many randomized controlled trials describing the use of intravenous methadone in cardiac surgical patients, and none in Chinese population. Results from this study will lay the foundation for future large-scale studies on intravenous methadone use in cardiac surgery, which has the potential to improve the quality of recovery by optimizing acute and chronic pain management. This is also the first study to demonstrate perioperative changes in plasma concentration of methadone in cardiac surgery.
Ethics and dissemination
The Joint CUHK-NTEC Clinical Research Ethics Committee approved the study protocol (CREC Ref. No.: 2022.636-T). The findings will be presented at scientific meeting, peer-reviewed journals and to study participants.
Trial registration number
NCT05913284
Trial registration URL
https://clinicaltrials.gov/study/NCT05913284
Creativity and Entrepreneurial Orientation in Early-Stage Tech Startups: A Cross-Countries Study in Australia, New Zealand, and Singapore for Sustainable Development
Authors: Magableh Khaled Naser , Kannan Selvi
Published: March 2024

This study shows how early-stage tech entrepreneurs leverage creativity and entrepreneurial orientation (EO) to enhance the odds of their new ventures’ success. A total of 20 entrepreneurs from tech startups in Australia, New Zealand, and Singapore were interviewed using a qualitative approach. Data was collected from semi-structured interviews and analysed using NVivo 12 Plus. The findings reveal the vital role of personal competencies such as storytelling, business skills, and proactive learning in enabling entrepreneurs to exhibit creativity and innovativeness. Interpersonal competencies, including relationship building and risk encouragement, empower entrepreneurs to demonstrate proactiveness and competitive aggressiveness. Managerial competencies, such as creative problem-solving, customer focus, and vision articulation, help entrepreneurs manifest leadership abilities and enhance autonomy and creativity, emphasising their critical role in fostering EO dimensions and creativity among early-stage entrepreneurs. Moreover, the insights gained from this study can contribute to achieving the United Nations Sustainable Development Goals (UNSDGs).
Analysis of mitogenomes from the family Keratoisididae reveals mitonuclear discordance and the presence of unknown open reading frames
Authors: Morrissey Declan , Quattrini Andrea M. , Allcock A. Louise
Published: March 2024

Historically, evolutionary studies have not been able to resolve relationships within Octocorallia but recent advances in genomic techniques have allowed large numbers of Ultra Conserved Elements and exons, collectively referred to as conserved elements, to be extracted from the nuclear genome. Few studies have compared evolutionary histories generated with these conserved elements and with those inferred from complete mitochondrial genomes. We examined the characteristics of 26 complete mitogenomes and constructed both mitochondrial and nuclear (1418 conserved elements) phylogenies of the family Keratoisididae, a prolific group of exclusively deep-sea corals. Relationships among most keratoisidid groups were well supported by the conserved element phylogeny while many relationships were unresolved from mitogenomic inferences. In addition, some incongruences were observed. The position of keratoisidid groups F1 and I4, and the observed polyphyly of D2 in the nuclear inference phylogeny, provide evidence for mitonuclear discordance within the group. Multiple novel Open Reading Frames (ORFs) of unknown function were found in the mitochondrial genome between cob and nad6. These ORFs ranged in size from 84–537 bp and were present in all examined mitogenomes except those assigned to keratoisidid group A1 which only have a 10 bp gap between coding regions. Further investigation is required to determine whether these ORFs are expressed and, if so, what function they have. The presence of mitonuclear discordance within the family indicates that phylogenies constructed with concatenated mitochondrial and nuclear markers may be inappropriate.
T-cell receptor triggering requires inactivation of Lim kinase-1 by Slingshot-1 phosphatase
Authors: Roda-Navarro Pedro , Gómez-Morón Álvaro , Alegre-Gómez Sergio , Ramirez-Muñoz Rocio , Hernaiz-Esteban Alicia , Carrasco-Padilla Carlos , Scagnetti Camila , Aguilar-Sopeña Óscar , García-Gil Marta , Borroto Aldo , Torres-Ruiz Raul , Rodríguez-Perales Sandra , Sanchez-Madrid Francisco , Martin-Cofreces Noa
Published: March 2024

Actin dynamics control early T cell receptor signalling during T cell activation. However, the precise regulation of initial actin rearrangements is not completely understood. Here, we have investigated the regulatory role of the phosphatase Slingshot-1 (SSH1) in this process. Our data show that SSH1 rapidly polarises to nascent cognate synaptic contacts and later relocalises to peripheral F-actin networks organised at the mature synapses. Knockdown of SSH1 expression by CRISPR/Cas9-mediated genome editing or small interfering RNA revealed a regulatory role for SSH1 in CD3ε conformational change, allowing Nck binding and proper downstream signalling and immunological synapse organisation. TCR triggering induced the SSH1-mediated activation of actin dynamics through a mechanism mediated by Limk1 inactivation. These data suggest that during early TCR activation, SSH1 is required for early F-actin rearrangements that mediate initial conformational changes of the TCR, integrin organisation and proximal signalling events for proper synapse organisation.
Development and evaluation of the internal consistency of the Spanish version of the Dentine Hypersensitivity Experience Questionnaire-15 (DHEQ-15)
Authors: D’Eramo Luciana , Vila María Florencia Escalante , Sánchez María Laura , Salgado Pablo Andrés , Rösing Cassiano K , Squassi Aldo
Published: March 2024

Background: Dentine hypersensitivity (DH) is a prevalent yet understudied pain condition that affects millions of people worldwide. Assessing self-reported DH experiences is crucial for research and clinical management. This study aimed to develop and evaluate the internal consistency of the Spanish version of the DHEQ-15, a short, validated questionnaire for this purpose.
Methods: A two-stage approach was employed. The first stage involved cross-cultural adaptation of the DHEQ-15 through forward-backward translation, pilot testing, and expert review. The second stage was a cross-sectional study with 2,530 dental patients who completed the translated DHEQ-15 and answered questions about their overall oral health. Internal consistency was assessed using Cronbach's alpha and item-to-total correlations. A receiver operating characteristic (ROC) curve was used to establish a cutoff point for identifying individuals with significant DH based on their DHEQ-15 score and a dental examination.
Results: The final Spanish DHEQ-15 demonstrated excellent internal consistency, with a Cronbach's alpha of 0.961. All item-to-total correlations were above 0.4, indicating good item discrimination. The ROC curve analysis identified a cutoff point of 26 for the DHEQ-15 score, with an area under the curve of 0.773.
Conclusions: The Spanish DHEQ-15 is a reliable and valid tool for assessing self-reported DH experiences in Spanish-speaking populations. The established cutoffpoint of 26 can assist in identifying individuals with DH who might benefit from clinical intervention. This culturally adapted instrument holds promise for facilitating research, improving clinical management, and ultimately enhancing patient care in DH.
An Integrated Bioremediation Approach for Wastewater Treatment and Contaminated Soil Remediation in a Used Oil Recycling Plant
Authors: Jemli Meryem , Karray Fatma , Mansour Lamjed , Loukil Slim , Bouhdida Rihab , Aleya Sami , Sayadi Sami
Published: March 2024

This work focused on the biotreatment of wastewater and contaminated soil in a used oil recycling plant located in Bizerte.
A Continuous Stirred Tank Reactor (CSTR) and a Trickling Filter (TF) were used to treat stripped and collected wastewater, respectively. The CSTR was started up and stabilized for 90 days. Over the following 170 days, the operational organic loading rates (OLR) of the TF and the CSTR were around 1200 and 3000 mg chemical oxygen demand (COD) L-1 day-1, respectively.
The treatment efficiency was 94% for total petroleum hydrocarbons (TPH), 89.5% for COD, 83.34% for biological oxygen demand (BOD5) and 91.25% for phenol. Treated industrial wastewater from the TF was used for bioaugmentation (BA) of contaminated soil. The BA strategy was compared with natural attenuation (NA) based on the use of tap water. The assessment of the soil took 24 weeks to complete.
The effectiveness of the soil bioaugmentation strategy was confirmed by monitoring of phenolic compounds, aliphatic and polycyclic aromatic hydrocarbons (AH and PAH), heavy metals and germination index (GI). The biodegradation rate of contaminants was improved and the time required for their removal was reduced.
The soil bacterial communities were dominated by species of the genera Mycobacterium, Proteiniphilum, Nocardioides, Luteimicrobium and Azospirillum, which were identified as hydrocarbon and phenol degrading bacteria.
The bioremediation of polluted soils by the treated industrial effluents seems to be an interesting approach for the conservation of water and soil resources.
Investigation on nonlinear dynamics and fatigue damage of a simply supported tube with clearance restriction in tube bundles subjected to two-phase flow
Authors: Yang Shihao , Lai Jiang
Published: March 2024

A mathematical model of a simply supported tube with clearance restriction in an otherwise rigid rotated triangular tube array subjected to two-phase flow was established in this study. The nonlinear vibration responses of the tube bundles system were calculated, and the fatigue damage evaluation were carried. The relationships between the fatigue damage and collision behavior are obtained. The numerical results indicated that the reduced velocity has an obvious effect on the dominant frequency, the collision frequency, and the equilibrium position the system. The nonlinear dynamic characteristics of simply supported tube with clearance restriction in an otherwise rigid rotated triangular tube array may essentially determine the fatigue damage results.
YouTube/ Bilibili/ TikTok Videos as Sources of Medical Information on Laryngeal Carcinoma: Cross-Sectional Content Analysis Study
Authors: Liu ZeYang , Chen YiWen , Lin Ying , Ai MaoMao , Lian DongLing , Zhang YuanHui , Shen YanXiong , Yu Feng
Published: March 2024

Background YouTube, a widely recognized global video platform, is inaccessible in China, where Bilibili and TikTok are popular platforms for long and short videos, respectively. There are many videos related to laryngeal carcinoma on these platforms. This study aims to evaluate the quality of the relevant videos and to analyze audience interaction on YouTube/ Bilibili/ TikTok.
Methods On January 1, 2024, we searched the top 100 videos by default sort order (300 videos in total) with the terms “laryngeal carcinoma” and “throat cancer” on YouTube, “喉癌” on Bilibili and TikTok. Videos were screened for relevance and similarity. Video characteristics were documented, and quality was assessed using the Patient Education Materials Assessment Tool (PEMAT), Video Information and Quality Index (VIQI), Global Quality Score (GQS), and modified DISCERN (mDISCERN).
Results The analysis included 99 YouTube videos, 76 from Bilibili, and 73 from TikTok. Median video lengths were 193s (YouTube), 136s (Bilibili), and 42s (TikTok). TikTok videos demonstrated higher audience interaction, while Bilibili had the lowest ratio of original content (69.7%). Treatment was the most popular topic on YouTube and Bilibili, while that on TikTok was the prognosis. Solo narration was the most common video style across all platforms. Video uploaders were predominantly non-profit organizations (YouTube), self-media (Bilibili), and doctors (TikTok), with TikTok authors having the highest certification rate (83.3%). Video quality, assessed using PEMAT, VIQI, GQS, and mDISCERN, varied across platforms, with YouTube showing the highest scores in general. Videos from professional authors performed better than videos from non-professionals based on the scores of GQS and mDISCERN. Spearman correlation analysis showed no strong relationships between the video quality and the audience interaction.
Conclusions TikTok, a short video platform, despite being more interactive, tends to offer less information and is of lower quality compared to long video platforms. Yet, a greater number of non-professional authors on Bilibili degraded its video quality. Though videos on YouTube are of the best quality, the video quality across all platforms needs enhancement. We need more professional uploaders to ameliorate the video quality related to laryngeal carcinoma.
Improving Data Quality and Information Use through Capacity Building and Mentorship Program in Ethiopia: Best Practices and Lessons Learned
Authors: Belay Hiwot , Demboba Wubshet , Mohammedsanni Afrah , Atnafu Asmamaw , Gutema Keneni , Amare Getasew , Abera Netsanet , Gebeyehu Abebaw
Published: March 2024

Background: The Capacity Building and Mentorship Program (CBMP) is a collaborative initiative of the Federal Ministry of Health of Ethiopia (FMOH) and selected Universities to enhance the Information Revolution Agenda. Recently, the FMOH declared that some CBMP implementations woredas are models. Therefore, assessing the best practices and lessons learned among the model woredas is essential for the success and scalability of the program. This study explores the best practices and lessons learned and their implications for creating a learning health system.
Methods: - A descriptive exploratory case-study design was conducted in four verified model woredas and one town administration across three regions: Amhara, Sidama, and Benishangul-Gumuz of Ethiopia. The study involved interviewing forty-two informants who were purposively selected from the model districts. A semi-structured interview guide was used to explore information on the Performance Monitoring Team (PMT), data management, analysis, visualization and use, capacity building, and infrastructure. The data collected was analyzed thematically using Atlas ti. 8 software.
Results: - Six themes were explored in this study: technical, behavioral, organizational intervention, health information system performance improvement, sustainability, and challenges. Need-based and practical capacity-building training, local resource mobilization, leadership engagement, HIS task audit, HIS accountability framework, reward, and recognition were some of the critical best experiences and lessons to be shared. Besides data visualization and dissemination, the Performance Monitoring Team (PMT) functionality and quality improvement project using strategic problem-solving approaches enhanced the intervention implementation. This study asserted local resource mobilization, leadership engagement, and institutional capacity building as critical factors for the sustainability of existing achievements. However, staff shortage and turnovers, job evaluation grading complaints, and low competency of medical record unit staff were existing challenges affecting the sustainability and scalability of the best experiences and lessons.
Conclusion and recommendation: - Numerous best experiences and lessons are identified among model districts. Need-based and practical HIS capacity-building training, leadership engagement, local resource mobilization, and HIS accountability framework were scalable and replicable best experiences and lessons. However, staff shortage and turnover, local Health Information Technician complaints, and contextual factors must be considered while scaling up to other areas.