bluuebunny/crossref_metadata_2025 huggingface dataset:
Digital Pore Pressure Prediction for Well Drilling Using Machine Learning in a Deep Shale Gas Field
Authors: Yue W. H. , Liu P. , Wen R. , Gou Q. Y. , Li Q. S. , Xu E. S. , Ling W. T , Huang Y. J. , Ren X. X. , Yu T. , Ninsom C. , Doan D.
Published: August 2024

Abnormal pressure and wellbore instability are the main challenges during drilling in shale gas reservoirs. Traditionally, the pre-drill predictions of pore pressure and wellbore stability are executed manually by geomechanics engineers. The procedures are usually complicated and take time, the results also highly depend on the executor's expertise. All these make pore pressure and wellbore stability prediction far from ideal and automatic. In this study, we utilized machine learning methods to perform prediction in a simpler manner. The digital models were trained with existing well data, geology data and drilling data, and were correlated with spacing coordinates, that contains geological structure information. The models on formation materials properties are trained and learnt with patterns recognition; the pore pressure, earth stresses and wellbore stability are trained with physics-based hybrid algorithm. The trained models are then used to predict pore pressure and mud weight window at any point in subsurface or along any planned well trajectory, to identify drilling risks and recommend solutions.

This approach was applied and validated in a deep shale gas field in Sichuan basin, China. In this field, the main shale gas reservoirs are overpressured and severe drilling complexities were encountered in drilling. Horizonal development wells are planned to drill to enhance production. This requires pre-drill pore pressure and wellbore stability prediction. Due to multiple abnormal pressure mechanisms and subsurface complexity, manual methodology is usually time-consuming, and the results are not consistent with different executors. With the developed new machine learning method, the digital models were trained with eleven geology surfaces and well data from eight existing wells. The trained model was used to predict pore pressure and mud weight window, including formation collapse pressure, mud loss pressure and breakdown pressure. The machine learning prediction of planned horizontal well Y14H and well Y15H were then compared against manual results calculated by geomechanics experts. The digital results matched well with manual results. The actual drilling results of well Y15H also confirmed the accuracy of the machine learning method. In well Y15H drilling, there were no drilling complexities and hole enlargements as using mud weight optimized with machine learning prediction. After well completed, the results showed that the pore pressure difference was only 0.5% between downhole measurement, 53.1MPa, and machine learning prediction, 52.8MPa. The minimum horizontal stress difference was about 5% between machine learning prediction, 72.88MPa, and downhole measurement, 76.76MPa. This field study confirmed the accuracy, effectiveness, and efficiency of machine learning method.
Holistic Approach in Dealing with Accelerated Plug and Abandonment (P&A) Project to Mitigate Gas Leak
Authors: Razak M. N. Abdul , Hamid A. Abdul , Zawawi A. , Khalid M. , Shah S. Masroll , Ezani F. S. , Sellapan S.
Published: August 2024

An incident of a gas leak was reported on an offshore platform in Malaysia. Observers noticed a gas cloud emerging from a well on the platform, accompanied by water and mud returning to the conductor and surface casing of the wellhead. At the same time, a drilling rig was operating on an adjacent platform. As a result of this incident, an immediate evacuation was carried out on the platform, and incident control measures were implemented on the drilling rig. The management made the decision to address the gas leak problem by plugging and abandoning (P&A) the well before resuming production and drilling activities on the platform. Production was halted, and drilling operations were suspended until the well was secured, causing financial and production losses for the company.

Within a month of preparation, the HWU Rig, along with well services, was mobilized to an offshore location. This paper discusses on the comprehensive planning, challenges, steps, and arrangements involved in the execution of the plug and abandonment (P&A) project. The topics covered range from rig readiness and acceptance to engineering planning, contracts, manpower, services, governance, and more. Various stakeholders, such as Facilities, Production, Intervention, and others, collaborated to make this endeavour feasible. All these parties were brought together as a cohesive team to ensure its success.

The traditional approach to project execution, which has been widely accepted in the industry for many years, is being strongly challenged by fast-track projects. This project demanded added flexibility in decision-making processes, without compromising governance and safety. The project team encountered various challenges and devised solutions to achieve project success. Some of these challenges and solutions include:

HWU Rig Readiness and Acceptance – Partial acceptance was conducted at different locations to meet the project timeline. Acceptance requirements were innovatively engineered to suit the time constraints. Stakeholder Management – Multiple stakeholders were integrated to enable concurrent activities and resource sharing, thereby minimizing costs and improving efficiency. Engineering & Technology – Offline jobs were performed on the well to gather more information and optimize time. New technologies (First In the world Technology Application – Perf, Wash & Bismuth) were explored and deployed to enhance assurance and ensure the secure P&A of the well.

This paper highlights the significance of meticulous planning, engineering, and an innovative approach in successfully executing a time and cost-constrained fast-track project. The collaborative efforts of numerous stakeholders were essential in ensuring that the project was accomplished while upholding governance and safety standards. This approach facilitated the implementation of cutting-edge technology at each stage, setting a benchmark for excellence.
Enhancing Red Zone Safety in the Drilling Industry: A New Metric for Quantifying Risk Exposure
Authors: McGuire T. , McCormick C. A. , Martin T. , Reixach D
Published: August 2024

There can never be enough useful tools in the offshore drilling industry's safety management systems when pursuing the furtherance of crew safety while improving operational performance. As Transocean worked on this goal, it was determined the exposure rate of personnel during critical operations was not being taken into consideration to show the overall impact technology has in reducing personnel risk. Additionally, no industry established metric existed to quantify personnel exposure and reduction once a new technology was introduced.

To address this, Transocean established a new metric called the Red Zone Exposure Rate (RZER) to assist in quantifying the baseline and reduced risk once new technologies are introduced. Utilizing real-time location systems, such as HaloGuard®, paves the way to further minimize personnel exposure to the red zone by evaluating the adherence and effectiveness of operational procedures and automates the measurement of the RZER metric. Other technologies designed to automate operations and move personnel away from the red zone, include Robotic Riser System and Rotary Multi-Tool, all of which reduce the need for manual intervention in high-risk zones. The RZER metric can now be utilized to quantify the benefit each of these technologies provide in reducing the red zone exposure rate to personnel on the rig on which the technology is deployed.

This paper covers the development of the new RZER metric that offers industry-wide application, how the new metric can be leveraged and practical applications for the metric across the industry to help achieve the goal of minimizing red zone exposure.
Rig with MPD Single Choke Integrated Solution and Advanced Drilling Automation Delivers a Record in the Delaware Basin
Authors: Kocsis A.
Published: August 2024

The Operator desired to keep Mud Weight (MW) as low as possible to avoid potential losses in the Brushy Canyon formation. Once passed the Brushy Canyon intermediate section they needed Managed Pressure Drilling (MPD) to maintain higher Equivalent Mud Weight (EMW) in the production curve and lateral to maintain wellbore stability and mitigate influxes by applying Surface Back Pressure (SBP) to increase Bottom Hole Pressure (BHP) at the base of the curve.
Achieving the Impossible: Making Factory Style Offshore Asset Retirement a Reality
Authors: Peerapat Sinlawat , Aaftaab Kharbanda
Published: August 2024

Chevron Thailand has been operating in the Gulf of Thailand for over 50 years. Several thousands of wells were developed and provided the energy foundation to the Kingdom of Thailand. Plug and Abandonment (P&A) is an obligation and part of the decommissioning activity at the end of these wells’ life. With aging wells and facilities together with the approaching of production ending period in Block 10-13, Chevron Thailand were looking at the seemingly impossible task of carrying out well P&A programs of a vast amount of offshore depleted wells with a very limited timeframe.

While envisioning the project, standardization of the planning process, Customization of the drilling rig, selecting performance-oriented service partners and building a culture of continuous improvement during the execution phase were setup to be the key drivers for success. From Jan 2020 to Apr 2022, amid the COVID19 pandemic, Chevron Thailand performed Plug and Abandonment on more than 3500 wells, with continuously improving efficiency, and returned the G1 concession to the Thai government.

This paper reviews the planning, technical and process aspects of this incredible project that led to this remarkable outcome.
Drill Out Long Interval Hard Cement and Metal Plug Using Coiled Tubing at Sidetracked Well: Lesson Learned from Mahakam Offshore Campaign, Indonesia
Authors: Bogianto R. W. , Rahmadhani M. I , Kristanti F. Y. , Kurniawati P. S. , Tampubolon H. F. , Panjaitan R.
Published: August 2024

Objectives/Scope

With the current mature production environment, massive drilling campaign is subject for cost efficiency to unlock marginal reserve in Mahakam Offshore Field which also lead to unexpected problem and restrict the production of the well, such as under displace problem during cementing job which result cement presence inside production tubing. A rigless intervention job such as drill out cement operation is required to regain access from restriction and unlock well potential.

Method, Procedures, Process

The decision to utilize coiled tubing for cement removal was driven by its ability to offer small equipment footprint & cheaper drill out cement cost from snubbing or electricline. Maximum coiled tubing yield strength (up to 53,000 lbs) and circulating pressure (up to 4,500 psi) will limit the pumping rate that can be applied, thus it will be the challenge to reach critical annular velocity for lifting cuttings so periodical long sweep need to be done. The simulation shows maximum net of WOB that can be applied to bit around 3881 lb, to compensate low WOB it is proposed to gradually increase the flow rate until got optimum ROP.

Results, Observations, Conclusions

The operation used cement mills, such as turbo scale mills and junk metal muncher mills, to clear wellbore access until float collar depth. Mill bit several times got stopped at downhole safety valve depth and needed to be pumped to be able to pass through without damaging the downhole valve. Mill bit inspection result after the operation shows the rubber of the stator got damaged and plugged the bit nozzle, thus, decreasing the rate of penetration. High pulling weight occurred frequently due to annular velocity not being achieved and cuttings locked up at the tangential section, thus, many long sweep is needed and prolong the operation. The drill-out operation of approximately 2,200 ft of hard cement and metal plug using coiled tubing was successfully done with a cost of about 500,000 USD and a duration of 24 days, with a production gain of 11 million cubic feet gas per day and 800 barrels of condensate per day. The successful of pilot well, the engineering review and the implementation of specific mitigation strategies set a strong foundation for considering the very shallow reservoir as a development target and industrialized. This determination can be solidified by evaluating the results from multiple trial campaigns to give solid safe conclusion in producing very shallow reservoir with robust and comprehensive data.
Carbon Capture Storage (CCS) Drilling & Completion Well Integrity Lifecycle Challenges & Mitigations
Authors: Picha Mahesh S
Published: August 2024

The growing global awareness of international climate change has compelled the global industry to take responsibility for reducing greenhouse gas emissions. As part of an Oil and Gas Operator's strategy to address this issue, a roadmap has been developed to capture and store carbon dioxide (CCS). This paper provides insights into CCS projects that employ a Storage Development Plan (SDP), which involves separation of CO2 from existing oil and gas producing fields with high CO2 content, and then reinjecting it into reservoirs with essential caprock geological seals for containment. Injector wells, either newly drilled or retro-fitted from existing fields, will be utilized to inject and store the produced CO2. Ensuring the integrity of all wells is crucial for preventing CO2 leakage and ensuring long-term containment sustainability along the wellpath, including both existing Plug and Abandonment (P&A) wells and active ones that intersect the chosen CO2 storage reservoir, as illustrated in Figure 1

The development wells within the identified depleted gas field have exceeded 30 years in age and were originally designed without considering the presence of high CO2 concentrations in the reservoir. The possibility of leakage along the wellbores due to accelerated corrosion, channeling, and cracks cannot be overlooked and necessitates thorough evaluation. A meticulous process has been implemented to assess the viability of converting existing producers into CO2 injectors. Discrepancies between the prescribed designs for gas production wells and CO2 injection wells dictate whether they can be repurposed for CO2 injection or need to be decommissioned. The determination of the optimal number of required CO2 injectors involves a screening process from fat to slim design approaches, utilizing corrosion-resistant alloy (CRA) materials and CO2-resistant cement to ensure lifecycle integrity. Maintaining an optimum angle between 40 to 60 degrees and sustaining the necessary injection pressure at the required rate for injecting supercritical CO2 over a 25-year period are critical considerations. Additionally, challenges during well execution, such as anti-collision risks and total loss scenarios while drilling in carbonate reservoirs, must be addressed. Completion design focuses on minimizing the number of completion components to reduce pressure differentials and potential leak paths from the tubing hanger down to the lower completion's end. Well design optimization from fat to slim has been conducted based on sensitivity analysis outputs from Software. Monitoring the well integrity lifecycle involves utilizing the latest-generation fiber optic technology for in-country value as well as acquiring seismic data for CO2 plume development.
Successfully Curing Dynamic Losses in a Highly Fractured Reservoir Section by Using an Engineered Self-Degradable Lost Circulation Material in a Field Trial in Middle East
Authors: Omer Mohammed , Fragachan Francisco E. , Strickland Samuel K. , Perez Gregory P.
Published: August 2024

Lost circulation of drilling fluids costs the oil and gas industry about $1 Billion USD per year, with the Middle East and North Africa (MENA) region accounting for most of such lost circulation events. Within MENA, these observed losses are due to the prevalence of natural fractures, especially in carbonate reservoirs. In a worst-case scenario, if not mitigated, lost circulation could lead to well control challenges, wellbore instability issues and potential loss of downhole tools and equipment. The challenge in MENA is further complicated by high-temperature reservoir sections, which may cause thermal instability of typically used polymeric lost circulation materials (LCMs).

In this case study, we used a geomechanics-based approach to create bridging and sealing at the fracture aperture using a bi-particle self-degradable lost circulation fluid system. The effectiveness of the system was assessed by considering interactions between particles and slurry fluid, with respect to the wellbore profile. The analysis was performed using an analytical model dictated by fluid density, viscosity, flow rate, and travel distance of LCM slurry, with the aim of minimizing issues related to dispersion and interface instabilities.

This paper discusses the results of our first successful field trial job in Iraq. The well had earlier experienced total losses amounting to 167,250 barrels (bbl), with the 6″ reservoir section only accounting for 9,050 bbl of the observed losses prior to using the bi-particulate self-degradable LCM system. This holistic geomechanics-based approach of designing LCM helped in curing losses in the highly faulted and fractured reservoir section. A 20-bbl pill of the bi-particulate system was pumped at 4.2 bpm and 51 psi via an open-ended pipe then displaced with 110 bbl. of water at 4.2 bpm and 81 psi at a depth of 9317 ft. The operator subsequently filled the string with 87 gpm and then increased flow in successive steps upto 250 gpm and observed no dynamic losses, allowing the well to be drilled ahead successfully. The LCM system was effectively able to stop the losses, allowing the hole section to be drilled successfully, after several attempts using traditional methods.

For the case study highlighted in this paper, the approach and LCM system was successfully able to prevent dynamic losses in the reservoir section without damaging the formation, hence confirming the viability of this technology and material. This model can be applied across the globe where similar challenges present themselves. This paper will provide an insight into ideas revolving around degradable LCM materials, as part of our commitment to make the industry cleaner and greener and minimize unwanted environmental impact.
Revolutionizing Casing Running: Redefining Efficiency with Automation
Authors: Nguyen Dianne Hernandez
Published: August 2024

The initial use of power tongs for casing connections has evolved into a more advanced method, involving the tie-in of a CRT (casing running tool) to the top drive in parallel to the rig's operating system to automate the operation. In integrated casing running, the common contributors to flat times have been identified in aligning the CRT tool into the joint, connection makeup, and intermittent filling up of the casing string with drilling fluid. The connection times from slips to slips, can vary from different factors such as the driller’s expertise, visibility of the CRT tool position, and the effectiveness of crew communication. Nabors Drilling Solutions recognized the areas where improvements were attainable through automation and implemented an engineered solution comprised of mechanical and software enhancements. This innovative approach delivered consistent casing connection times while eliminating the human error that can lead to misapplied torque and the risk of joint damage or cross-threading incidents. A field test conducted in West Texas demonstrated a 67% reduction in the time required for CRT alignment when compared to the conventional casing running method. This paper highlights the advancements achieved through automation and optimized processes in integrated casing running, improving performance and increased safety.
Drilling the Deepest Onshore Directional Well in Asia: Value of Good Planning and Systematic Execution on an Ultra-Extended-Reach Drilling Campaign
Authors: Zongqi Chen , Xianghua Liu , Shuanggui Li , Dengxiang Bai , Goke Akinniranye , Zhaoxiang Fan , Zhong He , Yang Yu , Shiying Liu , Jingfeng Li , Shengquan Wu , Qiang Hu , Fan Yang , Liuwei Li , Xianbing Wang , Ziliang Wang
Published: August 2024

The Yuejin 3-3XC well in the Tahe oilfield, located in the Tarim Basin of China, is more than just a drilling project. It is a scientific endeavor specifically designed to target the carbonate lithology of the Ordovician Yijianfang Formation. Commencing in 1980, the exploration of the field has resulted in over 2,300 wells drilled to date. The well profile of YJ3-3XC presented unique challenges, given the complexity of the geology and the geomechanical risks involved. However, the well was drilled and completed, making it Asia's deepest onshore extended-reach well. The findings from this project are a testament to our technical prowess and a treasure trove of knowledge for the industry. This paper comprehensively summarizes the work and progress in delivering Asia's deepest extended-reach drilling (ERD) project. It covers the technical challenges faced, the design solutions implemented, the operational practices adopted, and the systematic approach to well-planning that led to exceptional results. The paper also discusses the modeling and simulation work to plan and develop a comprehensive well program, real-time data to validate models resulting in significant cost savings, and the processes adopted to ensure team-wide understanding and commitment to delivering successful wells. Completing the YJ3-3XC well is not just a testament to the successful navigation of the region's unique geological and geomechanical challenges associated with deep drilling. It is a significant milestone, marking Asia's deepest onshore extended-reach well. The successful delivery of this project is a source of pride, demonstrating the importance of technical innovation, design solutions, and operational excellence in overcoming technical challenges in complex geological environments.
Blockchain Enabled Solutions for Efficient Drilling Waste Management- A Comprehensive Analysis
Authors: Krishnan A. Geetha , Thompson C. , Osgouei R. Ettehadi , Martinez J. , Rahman S.
Published: August 2024

The oil and gas industry faces significant environmental challenges in drilling waste management, given the risks posed to ecosystems and human health by contaminated drilling cuttings. Various techniques have been developed to manage and dispose of drilling waste, but traditional approaches have fallen short in waste tracking and regulatory compliance. Blockchain technology offers a promising solution by providing an immutable, transparent ledger of transactions, which can greatly enhance the traceability of waste management processes and improve regulatory compliance. This article explores the potential of blockchain to revolutionize waste management practices in the oil and gas sector, addressing long-standing challenges and aligning operations with global environmental sustainability goals.
LED-pumped room-temperature solid-state maser
Authors: Sathian Juna , Long Sophia , Lopez Lisa , Ford Bethan , Balembois François , Montis Riccardo , Ng Wern , Arroo Daan , Alford Neil , Torun Hamdi
Published: August 2024

Room-temperature MASERs (Microwave Amplification by Stimulated Emission of Radiation) are coherent sources that exploit stimulated emission to amplify electromagnetic waves at microwave frequencies. Here we demonstrate a light-emittting diode (LED)-pumped maser using pentacene-doped para-terphenyl as the gain medium. The LED light is brightness enhanced and guided using a Cerium-doped Yttrium Aluminum Garnet luminescent crystal that uses light recycling for enhanced luminance and increased power levels. We observe stable maser emission at 1.45 GHz using LED pumping with a duration of 200 µs and a microwave output power of up to 0.014 mW. This new maser is cost-effective, safe, outperforms non-laser pumped masers in output power, and environmentally friendly, ensuring various potential uses, including more sensitive magnetic resonance body scanners, quantum optical coherence tomography, advanced quantum computer components, portable atomic clocks, and improved radio astronomy devices for deep space exploration.
Pedestrian Face Recognition using CC Footage
Authors: Raghavendra C. , Reddy M. Purushotham , Reddy R. Obulakonda , Sriniva CH.
Published: August 2024

Face detection is a difficult job in the field of computer vision and image processing. Various applications are available, including video monitoring, remote device login, passport verification, etc. Based on current criminal histories, we can classify them by CC video in public places such as bus terminals, train stations, airports, pilgrim stations, public parks, shopping malls, etc. Whenever an individual matches a video clip, the machine must indicate the signal. With this experiment, when criminals are walking about in public areas, with the aid of CC cameras, we will recognise the criminals and take the appropriate steps. An individual may be re-identified between a video clip and a photograph, for example, in a case where a single image of him/her is used to re-identify a suspect from a large number of pedestrian recordings. We call this condition a re-identification video picture (IVPR). But basically, video and image are represented with a certain gap in characteristics, where there are, for the most part, immense differences between frames of each file. Such modules can only render matching functionality between video and picture a challenging challenge. To align the image with the video framework first, we need to distinguish the progress of the images from the video at that point, it will be possible to match the image efficiently by identifying the special features of the images. This re-identification proof can be made possible by using Scale-Invariant Function Transform (SIFT) Descriptors.
Comparing paper-based and mobile application for rank-based peer assessment in interprofessional education: before, during, and after the COVID-19 pandemic
Authors: Widyandana Doni , Utomo Prattama Santoso , Setiawan Ide Pustaka , Kurniawati Yustina Tyas , Dandekar Sucheta
Published: August 2024

Background:
Education was affected during the COVID-19 pandemic, and there was a need to adapt the learning approaches to the situation. At the University of Gadjah Mada, many essential soft skills of healthcare professionals are taught using the interprofessional education (IPE) approach on-site. Our university responded to this crisis by offering online classes and similar types of training. Post-administration of the course, a peer-assessment was conducted, and it was used to provide feedback on the work or performance of peers among students. Peer assessment was done using paper-based and a mobile application during COVID-19. This study aimed to share a best practice for the implementation of a rank-based peer-assessment application for longitudinal interprofessional education in the community setting and to compare the score distribution of a rank-based peer-assessment before and after using mobile application.
Methods
Quantitative research design was used by processing secondary data on student peer assessment scores from 3 bachelor programs (medicine, nursing, nutritionist) Community and Family Health Care with Interprofessional Education (CFHC-IPE) in Faculty of Medicine, Nursing, and Public Health, Universitas Gadjah Mada. 4,790 students from 2018 to 2022 (5 years) were tracked before, during, and after the COVID-19 pandemic. The assessments carried out were offline, online, and blended learning, respectively. The assessment was carried out using a paper-based method before and during the pandemic, online-based with a mobile application was used. Thus, the peer-assessment was conducted manually or using paper-based method using a 5-rank scoring system. In 2019, the peer assessment was carried out using a mobile application and applied a 10-rank scoring system.
Results
The rank-based peer assessment can be well implemented to make students assess their friends more objectively, with an average score 82.02 ± 8.68. The rightward shift in the distribution of scores indicates that the average score has improved after using the mobile application compared to before its use. (82.02 ± 8.68 vs 62.39 ± 11.13, p < 0.05).
Conclusion
The implementation of rank-based peer-assessment using a mobile application was well received during and after the pandemic by interprofessional undergraduate students. The online system made the assessment more objective and the average grades were seen to be better.
Electronic and Magnetic Transitions in Infinite Layer Nickelates by Strain-Orbital
Engineering
Authors: Zhang Yajun , He Xu , Yong Huadong , Wang Jie , Zhang Xingyi , Ghosez Philippe
Published: August 2024

Two-dimensional (2D) magnetic interactions, a single dx2-y2 band, and strong orbital splitting between dx2-y2 and d3z2-r2 orbitals are essential characteristics of cuprate superconductors. However, infinite-layer nickelates with small rare-earth ion display three-dimensional (3D) magnetic correlations, itinerant Ni d3z2-r2 band at the Fermi level, and weak orbital splitting between two eg orbitals, strikingly different from those of cuprate, which might be detrimental for superconducting properties. Here, through first-principles calculations, we predict that epitaxial strain in infinite-layer nickelates RNiO2 could fulfill the deliberate switching from 3D to 2D electronic and magnetic transitions. A general strain-orbital-spin relationship is proposed, and the strain controlled relative position of the localized Ni dx2-y2 band and itinerant Ni d3z2-r2 band are revealed to be the key ingredient that governs the Fermi surface and strength of the interlayer magnetic interactions. For RNiO2 with smaller rare-earth ion like DyNiO2, we propose that the desired cuprate-like electronic structure and 2D magnetic dimensionality could be successfully realized by compressive strain through tuning the energy level of Ni dx2-y2 and d3z2-r2 bands. We further develop a finite-temperature lattice wannier model and a Heisenberg spin model, which establish a complete temperature- and strain-dependent structural and magnetic phase diagram of epitaxial DyNiO2 thin films. Our work opens new perspective for the modulation of lattice, orbital, and spin states in infinite-layer nickelates and provides rich structural, electronic, and magnetic flexibility for the control of the superconducting-related properties.
WITHDRAWN: Developing a Risk Model of Lipid Metabolism-associated Genes: Implications for Clinical Prognosis and Tumor Immune Microenvironment in Gastric Cancer
Authors: Xiao Yanan , Yu Qin , Zhu Zewen , Zhou Shan , Wu Zhe , Luo Xin , Peng Hui , Zhan Zhiqiang
Published: August 2024

Background
Gastric cancer (GC) remains a significant clinical challenge due to its high mortality rate and complex pathophysiology. Recent advances have suggested that lipid metabolism plays a crucial role in the progression and prognosis of gastric cancer. This study aims to assess the implications of lipid metabolism-associated genes (LMAGs) in the molecular clinical prognosis and tumor immune microenvironment of GC.
Methods
We analyzed RNA-seq sequencing data from 371 GC transcriptomes in The Cancer Genome Atlas (TCGA) and 433 clinic datasets from the Gene Expression Omnibus (GEO). We selected the top 100 LMAGs for analysis. We applied univariate Cox regression to identify survival-related genes and used consensus clustering to explore molecular subtypes. We also performed copy number variation (CNV) and functional enrichment analysis. Using the LASSO and Cox regression analyses to construct and validate the GC-related prognostic risk model.
Results
A total of 3911 differentially expressed genes (DEGs) delineated distinct transcriptomic profiles between GC and normal gastric tissues were identified. Among these, 43 LMAGs were significantly associated with survival, most of which were poor prognostic factors. CNV analysis indicated prevalent gains in LMAGs in tumor samples. Consensus clustering revealed two distinct molecular subtypes (ARGcluster A and ARGcluster B) with significant differences in survival outcomes and gene expression profiles. Additionally, immune profiling revealed that ARGcluster A, associated with poorer outcomes, exhibited higher levels of pro-tumorigenic immune cells. Finally, we validated the expression, prognosis, and immune infiltration of fourteen key LMAGs in GC.
Conclusion
This study underscores the association between LMAGs with the prognosis and tumor immune microenvironment in GC. Further research is needed to validate these findings and explore potential therapeutic targets within the lipid metabolism pathway.
Polymeric Mixed Micelles with Triple Stimuli-Responsive Characteristics and Förster Resonance Energy Transfer Phenomenon for Drug Delivery System of Chemotherapy and Photodynamic Therapy
Authors: Lin Hong-Jia , Hong Li-Xuan , Wu Wen-Chung
Published: August 2024

In recent years, chemotherapy has been used in cancer treatment commonly. However, the hydrophobic property and non-selective apoptosis still limit its application. In recently, the drug delivery systems (DDS) such as polymer micelles, liposomes, and dendrimer are widely developed to improve the efficiency of chemotherapy. In this work, the amphiphilic polymer was used to encapsulate the Doxorubicin (DOX) through the self-assembly process to form the polymer micelles, and the drug release of DOX was controlled by the temperature-sensitive monomer (triethylene glycol methacrylate, TEGMA) and redox-responsive group (disulfide bond, S-S). On the other hand, the intracellular internalization was improved by the photosensitizer drug (protoporphyrin IX, PpIX) through the photochemical internalization (PCI) process. The lower critical solution temperature (LCST) of micelles in this work was 37.6 oC, and the in-vitro test showed that 96% of DOX was released under acid condition with high level of redox agent. Finally, the chemotherapy was confirmed by the cytotoxicity assays and confocal laser scanning microscope (CLSM).
Advanced Test Methodologies for Evaluation of Android Mobile Antivirus
Authors: Ryu Youngrak , Shin Kangsik , Lee Jeongho , Jung Dong-Jae , Cho Ho-Mook
Published: August 2024

The increasing reliance on mobile devices for sensitive activities has amplified the need for effective mobile antivirus solutions, particularly for the Android operating system, which is more susceptible to security threats due to its open source framework. This study aims to fill the gap in standardized evaluation criteria for mobile antivirus by developing comprehensive evaluation criteria and creating an experimental environment to assess various commercial antivirus products available on the Google Play Store. Key evaluation criteria included detection performance, resource optimization, update frequency, user-friendliness, and device compatibility. Results indicated that most antivirus products exhibited high detection rates, especially against financial malware, although there was notable variability in response times and update cycles, with two products significantly underperforming in both detection efficiency and speed. The study underscores the necessity for enhanced detection rules to reduce false positives and better handle potentially unwanted applications. This research provides a critical foundation for users to make informed decisions regarding antivirus products and for developers to improve the effectiveness of mobile antivirus solutions. Future work will focus on refining detection methodologies and expanding evaluation protocols to adapt to the rapidly evolving landscape of cyber threats, ensuring robust protection for mobile device users.
The genetics of fruit skin separation in date palm
Authors: Younuskunju Shameem , Mohamoud Yasmin A. , Mathew Lisa Sara , Mayer Klaus F. X. , Suhre Karsten , Malek Joel A.
Published: August 2024

The physical appearance of date palm (Phoenix dactylifera) fruit (dates) is important for its market value. Many date-producing countries experience significant financial losses due to the poor appearance of the fruit, skin separation or puffiness being a major reason. Previous research showed evidence linking the skin separation phenotype to environmental conditions. In this study, we show that there is both an environmental and genetic contribution to the fruit skin separation phenotype. We show that beyond environmental factors, genetics is a strong contributor to the most extreme skin separation in some cultivars. To investigate this further, a genome-wide association study was conducted using genome data from 199 samples collected from 14 countries that identified nine genetic loci associated with this phenotype and investigated genes in these regions that may contribute to the phenotype overall. Identifying the genetic factors may help better understand the biology and pathways that lead to the environmental effects on skin separation and improve commercial date production. In conclusion, our key finding is that both environmental and genetic factors contribute to skin separation variation, and improvements in environmental factors alone cannot overcome the extreme level of variation observed in some cultivars.
Non-structural carbohydrates dynamics of Pinus yunnanensis seedlings under three levels of continuous drought stress
Authors: Deng Xin , Chen Xin , Lan Ping , Li Tianyu , Yang Jingwen , Zhang Hang , Zheng Li , Liu Yaocong , Wu Junwen
Published: August 2024

There is limited understanding of how drought stress intensity and duration affect the dynamic changes of Non-structural carbohydrates (NSC) in various organs of seedlings, and there is a lack of consistent research results among different species. We performed experiments on the dynamics of NSC in different organs of Pinus yunnanensis seedlings under three continuous drought stresses from March 14 to May 12, 2021, respectively, with four levels of water gradients of suitable moisture (CK), light drought (LD), moderate drought (MD), and severe drought (SD). The results showed that the distribution of NSC in P. yunnanensis seedlings varied with drought stress intensity and duration. The NSC content of each organ (needles, stems, coarse roots and fine roots) showed different trends with the increase of drought stress intensity in different time periods, respectively. After 15d of drought stress, the intensity of drought stress had no effect on needle, stem and coarse root NSC contents, while the fine root NSC contents decreased significantly. At 30d and 45d, drought stress intensity had no significant effect on the NSC content of each organ. However, at 60d, the stem NSC content increased significantly under MD and SD conditions, while the fine root NSC content decreased significantly under SD conditions. With the extension of the drought duration, the coarse root NSC increased while the fine root NSC content decreased under SD conditions. The results showed that the drought duration played an important role in the dynamic change pattern of NSC, only a decrease in fine root was observed at the initial drought phase, and 60d was a turning point when significant changes in NSC occurred at the organ level. This is of great significance to better understand the dynamic changes of NSC in the organ level under drought stress.
Unstable collapse analysis of SPBS in saturated sand based on model experiment
Authors: Li Yunfa , Wu Guojun , Chen Weizhong , Yuan Jingqiang , Huo Mengzhe , Liu Yubiao
Published: August 2024

The instability of the tunnel face during shield tunnelling can lead to extensive surface subsidence in saturated sand, potentially leading to ground collapse accidents that pose a serious threat to the safety of surface infrastructure. In order to study the mechanism of ground collapse induced by face instability, a laboratory-scale slurry pressure balance shield (SPBS) machine system is employed to simulate the entire process of tunnelling. The soil pressure, pore water pressure, and surface subsidence response during unstable are revealed through multi-field monitoring. The morphological evolution characteristics of collapse pits are analyzed using 3D scanning technology. The experimental results indicate that: (1) The key to stable tunnelling is to balance the pressure in slurry chamber with tunnelling speed, which ensures the formation of filter cake in front of the cutterhead. (2) The torque of the cutterhead, soil pressure, and surface subsidence will respond significantly and synchronously when the tunnel face is unstable, whereas the soil and water pressures are relatively less noticeable. (3) Continuous tunnelling results in a gentler angle of repose and a wider range of collapse of the collapsed pit in the longitudinal direction. (4) The formula for predicting the duration of collapse is proposed which integrates the evolution patterns of the collapse pit effectively and has been well-validated by comparison with these experimental results. The study provides a reference for the safe construction of tunnel engineering in saturated sand.
Microbial community composition and Co-occurrence network analysis of the rhizosphere soil of the main constructive tree species in Helan Mountain of Northwest China
Authors: Yang Yuze , Li Yue , Hao Ke , Zhao Yujia , Fan Yongjun , Li Min
Published: August 2024

To understand the microbial diversity and community composition of the main constructive tree species, Picea crassifolia, Betula platyphylla, and Pinus tabuliformis, in Helan Mountain and their response to changes in soil physicochemical factors, high throughput sequencing technology was used to analyze the bacterial and fungal diversity and community structure. RDA and Pearson correlation analysis were used to explore the influence of soil physicochemical factors on microbial community construction, and co-occurrence network analysis was conducted on the microbial communities. The results showed that the fungal and bacterial diversity was highest in B. platyphylla, and lowest in P. crassifolia. Additionally, the fungal/bacterial richness was greatest in the rhizosphere soils of P. tabuliformis and B. platyphylla. RDA and Pearson correlation analysis revealed that NN and AP were the main determining factors of the bacterial community, while NN and SOC were the main determining factors of the fungal community. Pearson correlation analysis between soil physicochemical factors and the alpha diversity of the microbial communities revealed a significant positive correlation between pH and the bacterial and fungal diversity, while SOC, TN, AP, and AN were significantly negatively correlated with the bacterial and fungal diversity. Co-occurrence network analysis revealed that the soil bacterial communities exhibit richer network nodes, edges, greater diversity, and greater network connectivity than the fungal communities, indicating that the bacterial communities bacteria exhibit more complex and stable interaction patterns in soil. The research results can provide guidance for understanding the interactions between microorganisms in forest ecosystems and the relationships between microbial community composition and ecosystem functions.
Scalable Production of Bio-Calcium Oxide via Thermal Decomposition of Solid - Hatchery Waste in a Laboratory-Scale Rotary Kiln
Authors: Chuakham Suwanan , Putkham Ajchara I. , Chaiyachet Yuwadee , Saengprajak Arnusorn , Banlue Kriangsak , Tanpaiboonkul Nipon , Putkham Apipong
Published: August 2024

Chicken eggshell waste is an alternative renewable source for quicklime production. Eggshell waste has received significant attention from researchers due to it being a potential source of bio-CaO, which not only drives the circular economy concept but also supports sustainable development. However, experiments on the production of bio-CaO are normally conducted in a small lab-scale furnace. Furthermore, the eggshell raw material is collected from canteens or households, which is not suitable for economical or industrial production. Therefore, this study investigated the factors affecting the bio-CaO production from hatchery waste via both batch and continuous calcination process in a laboratory-scale rotary kiln for the first time. The eggshells were first separated from the solid hatchery waste. Then, the effect of preparation methods of raw eggshells on the properties of bio-CaO was investigated, e.g., eggshells with and without membrane separation, various particle sizes, and with an increase of the percent raw material filling in the kiln from 5–20%. Calcination of the samples was performed in a rotary kiln at 800°C with a 0.5 RPM rotating speed and a 5° inclination of the kiln. The effects of the calcination process in either an air or N2 atmosphere on the calcined product were also observed. Instrumental analysis shows that the production yield and purity of bio-CaO were in the range of 49–56 wt% and 97–98%, respectively. The results also indicated that the production yield of bio-CaO decreased to 17.7% with a decrease in the raw material particle size from 3.3 mm to 250 µm. Moreover, the production of bio-CaO with eggshells containing eggshell membrane decreases the purity of calcium oxide by about 0.7–1.0%. In addition, further increasing the filling volume of the kiln from 5–20% had only a slight effect on the purity and yield of the product. These results imply that it is not necessary to remove the eggshell membrane from the raw eggshells in order to produce industrial-grade CaO from the raw eggshell. These new findings can likely be used to develop an alternative process design to reduce the manufacturing cost of bio-CaO produced from hatchery waste. Furthermore, this present study reveals that the specifications of the obtained bio-CaO comply with both Thai industrial standards and international food additive standards.
Advanced sperm preservation techniques for yellow-spotted mountain newts (Neurergus derjugini): implications for genetic management and conservation
Authors: Taheri-Khas Zeynab , Gharzi Ahmad , Vaissi Somaye , Heshmatzad Pouria , Kalhori Zahra
Published: August 2024

Advances in cold storage and cryopreservation of amphibian sperm are critical for the genetic management and conservation of threatened species. This study represents the first investigation into the sperm of the yellow-spotted mountain newt (Neurergus derjugini), focusing on both short-term and long-term storage for future reproductive efforts. We examined the effects of seven extenders on sperm motility over time at three storage temperatures (4±1 °C, 9±1 °C, and 20±1 °C). Additionally, we assessed the impact of 16 cryoprotectants on sperm motility and morphology post-thawing. Following the identification of the most effective freezing medium, we evaluated sperm DNA fragmentation to ensure viability. Our results indicate that 10% Holtfreter’s solution is the optimal extender for short-term storage at all three temperatures, maintaining sperm motility for up to 15 days at 4 °C. For long-term storage, a combination of 10% Holtfreter’s solution and 10% DMSO was found to best preserve sperm motility, morphology, and minimize DNA fragmentation after thawing. These findings underscore the importance of specific extenders and temperature treatments in enhancing sperm functionality, thereby supporting successful assisted reproductive technologies (ART) for endangered species.