bluuebunny/crossref_metadata_2025 huggingface dataset:
How Downhole Conditions Impact Acidizing Performance in Carbonate Reservoirs?
Authors: Sayed M. A. , Chang F. C.
Published: October 2023

Carbonate reservoirs consist mainly of calcite or dolomite or a mixture of both minerals. Hydrochloric acid (HCl) is frequently injected to stimulate the productivity of such formations. At temperatures above 200°F the reaction rate between HCl and carbonate becomes so fast that the treatment can result in shallow penetration and face dissolution. The HCl-carbonate reaction kinetics is complicated by the released carbon dioxide (CO2) phase behavior.

Typical experiments on carbonate acidizing use 1,000 psi system back pressure as a mean to control the release of CO2 and keep it in the solution. The CO2 can be partially in the gaseous phase, which creates forced convection and therefore increase in apparent reaction rate. Acidizing treatments are usually performed at higher pressures, and temperatures, to push the acid to either create wormhole or etched fracture surfaces. The overestimated reaction rate due to the unrealistic experimental parameters can lead to underestimation of acid penetration and over-design of acid volume and injection rate requirements. The insight of pressure effect on acid-carbonate reaction rate has been published before. This paper is aimed at studying the combined effect of downhole condition of pressure and temperature on the acid and rock reaction rates and the overall performance (mainly wormhole propagation and structure) of the acid solution in more depth.

Core flooding experiments are performed to cover a wider range of parameters of permeability, injection rate, and more importantly pressures and downhole temperatures to simulate more realistic reservoir conditions. Core samples were scanned using a micro-CT scanner to evaluate the wormhole propagation inside the core sample. In addition, the kinetics of CO2 phase transition, the solubility of CO2 in water are also investigated as functions of pressure and temperature to help better explain the core flooding results.

It is found that the CO2 solubility in water at 300°F increases 4 times when pressure increases from 1500 psi to 8,000 psi. At 250°F and under similar conditions of injection rate and acid concentration, increasing the system pressure from 1,500 to 7,000 psi caused a 50% reduction in the acid volume needed to achieve breakthrough indicating an improvement in the acid penetration rate into the rock. At injection rate of 5 ml/min and under a pressure of 5,000 psi, 15 wt.% HCl breaks through core even at temperature as high as 350°F without causing any face dissolution. At high pressure, the HCl acid penetrates deeper than the preconceived notion because it is naturally more retarded than previously believed due to its full supercritical phase and higher CO2 solubility. It is very critical that the reaction rate measurements are performed under realistic downhole conditions to better simulate and design the acidizing treatment.
EMI Scanning Tubing at the Wellhead: What it is, What it isn't, and is it Worth it
Authors: Allison A. P. , Richardson C. L.
Published: October 2023

Tubing integrity in artificially lifted wells declines over time, primarily due to corrosion and wear. Corrosion may occur internally or externally on the tubing; wear caused by the movement of sucker rods will occur internally. It is difficult to visually inspect the inner surface of the tubing during workover operations, so some form of inspection equipment is often used to evaluate the condition of the tubing. This equipment may use electromagnetic (EMI) or gamma-ray technology to determine wall thickness, detect holes or splits, and may attempt to categorize corrosion vs. rod wear. This equipment can be operated as a portable unit at the wellhead during workover operations or may be permanently installed in an inspection facility. A series of trials were conducted to evaluate the performance of the portable inspection equipment vs. the equipment used at an inspection facility.

Five wells were selected to evaluate the performance of multiple tubing inspection systems. Two portable systems were tested: one used only EMI, and the other used both EMI and gamma-ray technology. After inspecting the tubing with both systems at the wellhead, each joint was numbered and laid down for testing at the inspection facility. A joint-by-joint comparison was made between the inspection results of both portable systems and the inspection facility.

The performance of the inspection facility equipment was significantly better than both portable systems. The inspection facility equipment consistently detected more flaws and wall loss on most of the test wells. One test well was determined to be majority red band by the portable equipment and was planned to be scrapped. The inspection facility testing determined most of this well's tubing was instead yellow band, successfully recovering this tubing for future use. The results of this trial led to the operator ending the practice of portable wellhead scanning for most wells and shifting to a combination of inspection facility testing and hydrostatic testing at the wellhead when necessary.

The comparison between portable and permanently installed equipment shows that portable scanning at the wellhead gives inferior results. Differences in the technology used between the portable and inspection facility equipment, along with differing operating practices, will be discussed to explain the significantly poorer performance of the portable equipment. The justification for ending portable wellhead scanning in most cases will be explained.
Pleito Creek: A Commercial Demonstration of a High-Pressure, In-Situ Combustion Process Using Enriched Air for Near Miscible Displacement of Heavy Oil to Horizontal Production Wells
Authors: Fraim F. M. , McGee R. A. , Dobson D. S. , Turta A. T.
Published: October 2023

Body Over the life of the Pleito Creek heavy oil reservoir in California, it was produced by primary recovery, by huff-n-puff air injection, stripper gravity drainage, and finally in-situ steam and carbon dioxide generation. The purpose of this thermal recovery review is to help the reservoir engineer choose an optimal thermal recovery method for deep heavy oil that has lower carbon dioxide emissions.
Maximizing Reservoir Contact Using Memory Quality LWD Logs in Real-Time from High-Bandwidth Wired Drill Pipe Telemetry Technology
Authors: Fakolujo K. M. , Mamman H. , Sobowale A. , Arab R.
Published: October 2023

Objectives of this technical paper is to share the outcome of how deployment of high-speed high-bandwidth unconventional wired drill pipe telemetry transmission of logging while drilling (LWD) to maximize reservoir contacts in an ultra-deep clastic gas reservoir. Real-time visualization and interpretation of images from higher bandwidth (57,600 bits per second) delivered memory quality formation evaluation logs in real time for timely critical decision-making and better well placement.

High-end drilling and logging technologies were used to optimize well placement in a challenging environment, including gamma ray (GR), resistivity, and density images enabling timely and full (360 deg) view of reservoir properties. The real-time near-bit GR image provided a clear stratigraphic interpretation that has been used for well placement. The deep azimuthal resistivity measurement and inversion provided critical reservoir vertical distribution away from the wellbore and guided well placement lookahead of time. The real-time density image provided hole shape information for mud weight adjustment on top of the stratigraphic information for well placement. The combination of all the above-mentioned measurements and high-speed telemetry was used for minimizing the risk associated with critical well placement decision-making and improving net to gross.

The above-mentioned technologies have been successfully applied to a well placement job. The memory quality data was transferred through wired drill pipe (WDP) to the surface in real time while geo-steering through a relatively heterogeneous sandstone reservoir with lateral facies variations. The real-time data was transferred to a centralized server for advanced processing and interpretation by team members to enable critical decision-making. As a result, more than 30% net-to-gross increase was achieved compared to the average net-to-gross from existing nearby horizontal laterals drilled in the same reservoir but with mud pulse telemetry (MPT) and basic logs.

The ability of WDP to transmit significantly extra images from log curves ensures higher bedding visualization and improves formation evaluation qualities, technical reliability and confidence. Real time high speed LWD data streams enhanced interpretation and subsurface geological mapping, minimizes bit trip through increase in ROP and maximizes well placement. This technology opens the gateway for any other advanced high-end LWD technology tool in the future.
Enhancing the Resolution of Micro-CT Images of Rock Samples via Unsupervised Machine Learning based on a Diffusion Model
Authors: Ma Zhaoyang , Sun Shuyu , Yan Bicheng , Kwak Hyung , Gao Jun
Published: October 2023

Objectives/Scope

X-ray Micro-Computer Tomography (μ-CT) has been widely adopted in earth science and petroleum engineering due to its non-destructive characteristic. Meanwhile, this three-dimensional-imaging method can be integrated with computer simulation to investigate petrophysical properties of reservoir rocks at pore scales. However, the application of μ-CT is limited by the trade-off between field of view and resolution, and it is challenging to indicate the pore structure of rocks, especially for shale or carbonate rocks. To address this issue, deep-learning-based super-resolution techniques have rapidly developed in the past few years.

Methodology

In this study, a super-resolution algorithm based on the state-of-the-art (STOA) diffusion model is proposed to generate super-resolved CT images for carbonate rocks. The proposed method adapts denoising diffusion probabilistic models to conditional image generation and performs super-resolution through a stochastic denoising process. Cascaded diffusion model is utilized to increase the training speed and generate high fidelity CT images. This method exhibits superior performance in the resolution-enhancement of CT images at various magnification factors (with a large scaling factor of up to 16) without the occurrence of image-noise and image-blurring issue, and the super-resolved CT images performs well for the calculation of petrophysical properties of carbonate rocks.

Results

This algorithm is applied to the carbonate rock and the performance of the diffusion model is evaluated by quantitative extraction and qualitative visualization. In addition, this method is compared with other methods, such as GAN, Variational Autoencoder, and Super-Resolution Convolutional Neural Networks (SRCNN). The results indicate that the built model shows excellent potential in enhancing the resolution of heterogeneous carbonate rocks. To be specific, the super-resolved images exhibit clear and sharp edges and a detailed pore network. In addition, it performs well on different upscaling factors (up to 16) and is superior to the existing super-resolution approaches (for both supervised and unsupervised algorithms). This study provides a novel deep-learning-based method using a diffusion model to enhance the resolution of μ-CT images of carbonate rocks (up to 16).

Novelty

The novelty of this study is three-fold. First, this method belongs to unsupervised learning, indicating that pairs of high-resolution and low-resolution CT images are no longer needed. Second, a large scaling factor (up to 16) is reached without an image-blurring issue, which normally occurs in other deep-learning-based super-resolution algorithms. Third, the quality of super-resolved images is promising and faithful when compared with other generated learning methods, such as Generative Adversarial Networks (GAN).
Deep Learning Based Upscaling of Geomechanical Constitutive Behavior for Lithological Heterogeneities
Authors: Ma Z. , Zhang B.
Published: October 2023

Large-scale coupled reservoir-geomechanical simulation is becoming a necessity for an in-depth assessment of subsurface energy developments such as hydrocarbon recovery and geological carbon storage, while a robust and efficient upscaling technique for the geomechanical constitutive behavior of heterogeneous reservoir is still missing to push forward the application of time-consuming coupled reservoir-geomechanical simulation. Here, we focus on the impact of lithological heterogeneity on the shear strength and stress-strain behavior and propose a deep learning-based upscaling technique that can provide the upscaled shear strength and stress-strain behavior from facies models and geomechanical parameters. The objectives of the proposed upscaling technique lie in the following two aspects: 1) bridge the gap between the fine-scale geological models and computationally efficient reservoir-geomechanical models used for large-scale subsurface energy development; 2) provide the upscaled realizations needed for geomechanical assessments considering geological uncertainties. The first step of the deep learning-based upscaling technique is generating a dataset that contains a sufficient number of data samples. Each sample consists of a randomly generated spatial correlated sand-shale realization (input) and the computed macroscopic shear strength and stress-strain behavior via finite element simulations (outputs). Using the assembled dataset, convolutional neural network (CNN) models are trained to build proxy models as an alternative for numerical upscaling. The trained CNN models can provide the upscaled shear strength (R2 > 0.95) and stress-strain behavior (R2 > 0.93) that highly agree with that from the computationally extensive numerical upscaling method in a much shorter time frame. The proposed deep learning-based upscaling technique can promote the application of large-scale reservoir-geomechanical simulation for geomechanical assessment and quantify the impact of geological uncertainties by conducting coupled simulations on a variety of reservoir realizations.
Deployment of Novel Optimized Multizone Single-Trip Gravel-Pack System
Authors: Mogga E. J. , Ismail A. , Adeyeba A. , Sanni I. , Kolakalapudi M. , Lopez M. , Lim C. , Yun M. , Zou C. , Moses N. , Barretto G , Goh K. , Lim Jia Yii , Gil J. , Chua D. , Razali R. , Dada O.
Published: October 2023

Brunei Shell Petroleum (BSP) constructs many wells that require active sand control for multiple zones in cased hole environment with the option for zonal selectivity and allowing watered out zones to be isolated through well intervention. The most frequently used tubing in these wells is 3½-in. tubing which poses selectivity challenge when used in the standard 9⅝-in. multizone single-trip (MZST) gravel-pack system because the standard system uses 5½-in. modular screens and screen valves which are operated using 4.5-in. hard OD shifting tool which cannot be ran through the 3½-in. tubing. An innovative optimized MZST gravel-pack system alternative was developed and implemented successfully in Brunei and across the industry. This system offers:

Higher accessibility and cost efficiency of MZST gravel-pack using conventional gravel-pack equipment. Selectivity option between zones during production Fluid loss control post gravel pack Improved rig time efficiencies Gravel-pack and Well Architecture Standardization

The optimized system maintains critical zonal selectivity capabilities through use of standard screens and an internal string that features conventional sliding sleeve doors (SSD) connected through a three-way sub. This configuration simplifies installation, optimizes cost, and streamlines deployment. Additionally, the system design satisfies the unique well requirements of isolating, stimulating, producing oil and gas from the distinct zones in a single run, thereby enhancing overall well economics.
The Labor Dimension of the Oil and Gas Industry in the Gulf: Role of Migrant and Expatriate Labor Force
Authors: Retnanto Albertus , Mohsin Anto , Aloudeh Zaina , Kazim Tayyibah
Published: October 2023

This paper highlights the role of the migrant and expatriate labor force and their contributions to the oil and gas industry in the Gulf. It would be instructive to acknowledge and learn from the working experiences and challenges faced by these migrant workers. Their backgrounds, skills, knowledge, and technical and managerial know-how have helped develop the oil and gas industry and, to a large extent, the economic development of the Gulf. Understanding their roles and contributions would serve at least two things. First, to appreciate the important part they took in the development of the Gulf oil and gas industry and hence to ensure the protection of their rights under local laws. Second, to tell a complete story of the Gulf's oil and gas industry and the country's development. In addition, multiple themes were examined, such as the challenges and rewards of working in the oil and gas industry in the Gulf, sustainability, and the work environment.

The main method used to acquire information regarding the labor dimension in the oil and gas industry in the Gulf was through semi-structured interviews. The interviewees were selected through a sampling technique known as snowball sampling. The interviews were then audio and video recorded with the interviewee's permission. After that, the interviews were transcribed and analyzed using a corpora analysis software, Lancsbox. The various themes were identified and used to write this research paper.

Some themes identified are the interviewees’ narratives and reasons for choosing to work in Gulf's oil and gas industry, their workplace challenges, their mentorship experiences, and their advice for young aspirant engineers. They also discussed and compared their professional and personal experiences in Gulf to other places they have worked. Knowing what they do and how they contribute would be beneficial for at least two reasons. First, to recognize the crucial part they play in the growth of the Gulf's oil and gas sector and, as a result, to ensure that their rights are protected by local legislation. Second, to provide a more thorough account of the country's gas and oil sector development.

Many international workers find satisfaction in the privileges and comfort their jobs, their host nation, and its thriving oil and gas industry offer them. They are drawn to the nation's multiculturalism, language, opportunities, and safety and want to keep giving back. That, however, does not come without the special difficulties highlighted in this research.
A Failsafe Method of Preventing Voltage Generation During Installation and Pulling of ESPs with Permanent Magnet Motors
Authors: Ken Saveth , Charles Booth , Mauricio Oviedo , Dennis Harris
Published: October 2023

With the increased use of permanent magnet motors (PMM) versus less efficient induction motors (IM) comes an increased safety risk. While both the IM and PMM can generate power themselves if their shaft is turned by external forces, the induction motor cannot generate enough power to require additional safety procedures. The PMM when spinning at 2,000 rpm can generate up to 240 volts to create a tremendous safety risk when one considers voltage over 50 volts can be lethal.

The objectives/scope of this paper is to present an alternative method of preventing the shaft of a Permanent Magnet Motor (PMM) from rotating during the install and pull process. The result of implementing this method is the creation of safer working conditions for the field technician. The alternative method presented here utilizes a mechanical lock to physically secure the shaft thereby preventing it from rotating while the lock is in place.

The mechanical lock mechanism is secured to the top end of the equipment string with the lock engaged during the installation of the Electric Submersible Pump (ESP) string. Once the motor is powered, the force generated automatically unlocks the shaft to allow for the normal operation of the ESP. To engage the lock for the pulling of the ESP string, a heavy weight is lowered on top of the shaft lock.

The two present methods to prevent the pump shaft from rotating while installing or pulling are shunting of the cable and plugging the production tubing. Shunting involves tying all three phases of the cable together to short circuit the electrical system. However, the potential to rotate still exists, but requires an extremely large force. Plugging the production tubing contains the fluid column's potential energy from flowing back through the ESP, but this too has its completion and operational issues. The mechanical shaft lock method described in this paper uses shear pins that physically lock the shaft to prevent it from rotating. Only the mechanical motor horsepower has enough force to shear the pins loose; downhole pressure is not enough. Utilizing a PMM mechanical lock mechanism will physically prevent the shaft from rotating while installing or pulling a PMM-ESP string to provide a failsafe method to prevent potentially fatal conditions.
Successful Milestones Achieved Towards High-Power Laser Drilling
Authors: Batarseh Sameeh I. , Alerigi Damian P. San Roman , Marshal Scott , Reduoane Kasri
Published: October 2023

This paper presents the critical successes towards developing high-power laser (HPL) drilling applications. The accomplishment of the recent field trial in a live well demonstrated that it is possible to mobilize a high-power laser system from the lab to the field and perform the first high-power laser operations. HPLs can penetrate different rock types regardless of their compressive strength in a safe, efficient, and cost-effective manner, providing a long-term solution and alternatives to several conventional operations.

Our work developed a comprehensive and stage-gated roadmap to deploy the technology for several upstream applications, including descaling, perforation, and drilling. This strategy is broken into sequential milestones, where each success enables progress to the next level. High-power laser technology has been tested and proven to effectively penetrate all types of rocks, regardless of their strength and composition, such as carbonate, shale, and sandstones. The field-ready HPL system builds on two decades of intense research providing a unique tool that enables safe and environmentally friendly operations. The portable system comprises a laser generator, a nitrogen tank, coiled tubing, energy conveyance cables, and the optical Bottom Hole Assembly (oBHA).

A successful milestone has been accomplished by integrating high-power laser components in the field, including splicing the energy conveyance cable to the oBHA and the laser generator in an open space. The tool was deployed using coiled tubing, which carried the energy and telemetry conveyance cable. The test demonstrated that the tool could effectively penetrate casing, cement, and formation in a live well. This achievement is the second successful milestone after HPL surface descaling towards enabling high-power laser drilling.

The technology offers unique features to drilling, such as precise control and orientation of the HPL to drill in any direction and through any formation. HPL drilling is independent of the reservoir's stress orientation and magnitude. An HPL system for drilling would be compact, environmentally friendly, and could drill and case simultaneously.
A web-based psychological support program for caregivers of children with rare chronic diseases: A randomized controlled trial
Authors: Tutus Dunja , Niemitz Mandy , Plener Paul L. , Fegert Jörg M. , Lehmann Christine , Weiss Christa , Knaevelsrud Christine , Biehl Lisa , Rassenhofer Miriam
Published: October 2023

Background
About 50% of rare diseases have symptom onset during childhood. A high level of nursing care and an often uncertain prognosis put caregivers of the affected children at high risk for psychological distress. At the same time, their caregivers have limited access to appropriate psychological care. Aim of this study was to evaluate a web-based psychological support program for caregivers of children with chronic rare diseases (WEP-CARE).
Methods
German-speaking parents (recruited between May 2016 and March 2018) caring for children aged 0–25 years with a rare disease, showing clinically relevant anxiety symptoms, were assigned to either WEP-CARE (n = 38) or a waitlist (n = 36) condition within a randomized controlled trial. Primary outcome measure was parental anxiety, assessed with the Generalized Anxiety Disorder Questionnaire (GAD-7). Secondary outcomes were: fear of disease progression, depression, coping, quality of life and user satisfaction. The group differences were tested through repeated-measures analyses of variance. The WEP-CARE group was additionally followed up three months after the treatment.
Results
A significant time-group interaction was found for anxiety (F(1,35) = 6.13, p = .016), fear of disease progression (F(1,331) = 18.23, p < .001), depression (F(1,74) = 10.79, p = .002) and coping (F(1,233) = 7.02, p = .010), suggesting superiority of the WEP-CARE group. Sustainability of the treatment gains regarding anxiety, fear of disease progression and coping was confirmed at the 6-month follow-up assessment (p < .01). A significant interaction effect could not be found for quality of life (F(1,2) = .016; p < .899). Both, participating parents and therapists were satisfied with WEP-CARE.
Conclusions
Our results underline efficacy and feasibility of WEP-CARE for parents of children with various rare diseases.
The utilization of date palm waste as an efficient adsorbent for the elimination of heavy metals from polluted water
Authors: Maitlo Amjad Ali , Jatoi Wahid Bux , Jakhrani Mushtaque Ali
Published: October 2023

This study focuses on the removal of heavy metal ions, such as cadmium (Cd2+), lead (Pb2+), Chromium (Cr6+), and Zinc (Zn2+) from water. Metals, which are often present in water, can have various origins i.e. industrial emissions, mining, melting, corrosion, municipal and industrial waste and agrochemicals. These metals have the potential to cause adverse effects on human health. The study employed activated carbon derived from date palm waste as a means of removing heavy metals. The activated nanoparticles were characterized using various analytical techniques, including SEM, ICP, XRD, BET, Raman, and FTIR analysis. Batch studies were conducted to optimize the metal ion adsorption onto the activated carbon of date palm waste. The adsorption process was evaluated using isotherm models and reaction kinetics under various conditions, including contact time, dosage, pH, and initial concentration. The findings of this study revealed that the prepared activated carbon from date palm waste effectively removed up to 85% of Cr6+, Pb2+, Cd2+, and Zn2+ ions from water. This study highlights the potential of using agricultural waste, such as date palm waste, for the production of effective adsorbents for heavy metal removal.
SARS-CoV-2 airborne infection risk in venues with different ventilation strategies – a comparison between experimental, numerical and analytical approaches
Authors: Geisler Sophia Mareike , Lausch Kevin , Hehnen Felix , Schulz Isabell , Kertzscher Ulrich , Kriegel Martin , Paschereit Christian Oliver , Schimek Sebastian , Hasirci Ümit , Brockmann Gerrid , Moter Annette , Senftleben Karolin , Moritz Stefan
Published: October 2023

The COVID-19 pandemic demonstrated that reliable risk assessment of venues is still challenging and resulted in the indiscriminate closure of many venues worldwide. Therefore, this study used an experimental, numerical and analytical approach to investigate the airborne transmission risk potential of differently ventilated, sized and shaped venues. The data were used to assess the effect size of different mitigation measures and to develop recommendations. In general, positions in the near field of an emission source were at high risk in all ventilation systems studied, while the risk of infection from positions in the far field varied depending on the ventilation strategy. Occupancy rate, airflow rate, residence time, SARS-CoV-2 virus variants, a high activity level and face masks affected the individual and global infection risk in all venues. The global infection risk was lowest for the displacement ventilation case and highest for the naturally ventilated venue. Therefore, in our study, a properly designed displacement ventilation system is the most effective ventilation strategy to keep airborne transmission and the number of secondary cases low, compared to mixing or natural ventilation.
Posterior corneal stability after small incision lenticule extraction with different optical zones
Authors: Yu Zhiqiang , Cheng Xueying , Zhao Yu , Fu Dan , Gao Ying , Zhou Xing-tao
Published: October 2023

Background: To assess the changes in the posterior corneal surface following small incision lenticule extraction (SMILE) with different optical zones.
Methods: In this retrospective study, 106 eyes of 106 patients who underwent SMILE were recruited 3 years after the procedure. Eyes were divided into two groups according to the size of the surgical optical zone: group A (52 eyes, ≤ 6.2 mm) and group B (54 eyes, ≥ 6.5 mm). Posterior central elevation (PCE) and 12 other points at 45°, 135°, 225° and 315° with distances of 1 mm, 2 mm and 3 mm from the centre were recorded from Pentacam.
Results: No iatrogenic keratectasia was identified, and eyes in the two groups showed comparable visual results. The overall trend in posterior corneal elevation changes was consistent for both groups. PCE decreased significantly from 1.33±2.32 to 0.75±2.41 in group A (P=0.024) and from 0.87±2.61 to 0.06±2.74 in group B (P=0.003). All points in the central 2 mm region in both groups were reduced postoperatively. In the 4 mm and 6 mm corneal annulus, almost all points at 225°and 315°showed backward displacement, with the most prominent change occurring at 315°in the 6 mm annulus (P<0.001), indicating no forward protrusion in the inferior area.
Conclusions: No forward protrusion in the posterior corneal surface was observed 3 years after SMILE with different optical zones. Comprehensive preoperative measurements are essential for ensuring corneal stability and avoiding iatrogenic keratectasia.
Study on reinforcement crossing in dry season and anti-floating scheme of drainage in wet season：A case study in Guiyang, southwest China
Authors: Ren Fangzhou , Liu Ning , Zhang Cong
Published: October 2023

Karst geomorphology is widely developed in Guizhou Province. In tunnel construction, it is common to cross over karst caves. Exposed karst caves bring great difficulty to tunnel construction. Karst water developed in karst caves will have a serious impact on tunnel lining and filling during tunnel construction and service. Taking Huangchongyan Tunnel passing through Karst hall of Tongzi to Xinpu Expressway in Guizhou Province as an example, this paper systematically analyzes the risks encountered in the process of crossing large karst caves. Through the comparison and selection of various treatment schemes for karst caves at home and abroad, a tunnel construction scheme of the whole life cycle is put forward. The scheme consists of tunnel reinforcement scheme for karst hall construction in low water period and drainage scheme for tunnel filling in high water period in future. Considering the karst water scour action exceeds the expectation during the service period of the tunnel, a 'bottom to up' reverse drainage structure is proposed, which can better meet the safety and durability requirements in the whole life cycle of the tunnel. Compared with the traditional method, it has the characteristics of strong foresight, short time limit and low cost, which can provide theoretical basis and construction reference for similar projects.
Clinical Case Analysis of Iliopsoas Hematoma Causing with Femoral Nerve Compression
Authors: Li Fubo , Peng Miao , Gong Gege , Ren Changhe , Ou Cehua , Zhang Yue
Published: October 2023

Background:To investigate the clinical manifestation and prognosis of iliopsoas hematoma (IPH) associated with femoral nerve compression and enhance the current understanding of IPH.Methods:Patients diagnosed with IPH from March 2014 to January 2023 at the Affiliated Hospital of Southwest Medical University were assessed. The main clinical indicator observed was visual analog scale (VAS) score before treatment as well as at 1 week and 1, 3, and 6 months after treatment. Secondary indicators included the degree of lower limb numbness before and after treatment, muscle strength, hip flexion degree, the distribution of affected nerves, hematoma size, and hematoma distribution.Results:A total of 28 patients were included, among which 24 were men, and the average age (median [interquartile range]) was 48 (20.25, 63) years. The average duration of disease onset was 3 (1.25, 7) days, and 16 patients (57.14%) exhibited coagulation dysfunction. After 1 week of treatment, a 50% reduction in the VAS score was noted in 18 patients (64.28%). Furthermore, VAS score at 1 week and 1, 3, and 6 months after treatment were significantly lower than the baseline VAS score (P< 0.05). Baseline lower limb sensation was grade I in two patients, followed by grades II, III, and IV in five, 11, and 10 patients, respectively. After 6 months, 22 patients (78.57%) recovered to grade I. Baseline muscle strength of the lower limb was grade II in one patient, while grades III, IV, and V were in 10, eight, and nine patients, respectively. After 6 months, 19 patients (67.85%) exhibited improvement to grade V. The baseline degree of hip flexion was graded I and II in 53.57% of the patients, with enhancement to grade III after 6 months in 25 (89.28%). Hematoma distribution was localized in the mid-zone in 21% of the patients; upper-mid zone, 29%; mid-lower zone, 29%; and upper-mid-lower zone, 21%. In terms of affected nerves, femoral nerve involvement was revealed in 25 patients (89.28%), whereas lateral femoral cutaneous nerve involvement in 15 (53.57%).Conclusions:IPH is mainly caused by coagulation dysfunction and is often accompanied by pain and femoral nerve involvement that result in slow neurological recovery. Furthermore, the timely detection and causal treatment of IPH may help achieve a favorable prognosis.
Antagonistic microbes isolated from fermentation broth of plant wastes against anthracnose of Camellia oleifera caused by Colletotrichum siamense
Authors: Hao Yalun , Zhou Liting , Guo Jun , Jin Chenzhong , Guo Kaifa
Published: October 2023

Camellia oleifera is an important edible oil woody plant in China. Anthracnose is a serious disease of C. oleifera, causing severe economic losses and posing a huge threat to the C. oleifera industry. The fungi Colletotrichum siamense is one of the main pathogens causing anthracnose of Camellia oleifera. In this study, antifungal activity of microorganisms isolated from fermentation broth against C. siamense were investigated for the first time. 8 strains were isolated and purified from fermentation broth. By morphological observation, gene sequence analysis, among the strains, 4 isolates were identified as Trichoderma harzianum and 4 isolates were identified as Bacillus subtilis. The result showed that 8 isolates displayed a relatively good potential on inhibiting the mycelial growth in C. siamense, but T. harzianum was more effective than B. subtilis as a biocontrol agent, with the best efficiency of 73.56%. In the vitro treatments, the combination of T. harzianum and B. subtilis were the most effective treatments in reducing the incidence and severity of anthracnose in C.oleifera, with the highest efficiency of 77.56%. It can be concluded that T. harzianum and B. subtilis are promising biocontrol agents to manage anthracnose in C.oleifera. These promising results provided valuable information on using fermentation broth of plant wastes as a new source of antagonists to control fungi disease.
Impact of Probiotic Lactobacillus plantarum ATCC 14917 on atherosclerotic plaque and its mechanism
Authors: Hassan Adil , Luqman Ameer , zhang Kun , Ullah Mehtab , Din Ahmad Ud , Xiaoling Liao , Wang Guixue
Published: October 2023

Background:
Atherosclerosis is viewed as not just as a problem of lipid build-up in blood vessels, but also as a chronic inflammatory disease involving both innate and acquired immunity. The most important feature of atherosclerosis is inflammation of the vessel walls, which play a vital role in both plaque instability and thrombotic blockage of arteries, which then cause stroke and acute coronary syndrome. Probiotics are living microorganisms that, when ingested in appropriate amounts, provide health benefits.
Aim:
The main goal of this research was to explore the impact of Lactobacillus plantarum ATCC 14917 (L. p ATCC 14917) on atherosclerosis plaque formation and its mechanism in Apo lipoprotein E-knockout (ApoE−/−) mice.
Methodology:
In this study ApoE−/− mice around 08-weeks old were randomly divided into three groups as; Normal group provided with normal chow, high fat diet group, gavage with PBS and Lactobacillus plantarum group provided high fat diet and gavage with L. plantarum ATCC 14917 (2 ×109 CFU/mL).
Results:
Our strain significantly reduced the plaque size of ApoE−/− mice by modulating the expression of inflammatory maker, immune cell markers and chemokine/chemokine receptors and tight junction proteins (TJP); concisely by down-regulating inflammatory marker (ICAM-1, CD-60 MCP-1, F4/80, ICAM-1 and VCAM-1) in thoracic aorta, (Ccr7, cd11c, cd4, cd80, IL-1β, TNF-α) in colon and by inducing ROS-scavenging enzymes (SOD-1 and SOD-2.), TJP's (occuldin. ZO-1, claudin-3 and MUC-3). Furthermore L. P ATCC 14917 administrations statistically lessened lipopolysaccharide (LPS) level in mesenteric adipose tissue.
Conclusion
Our results exhibited that our strain could reduce atherosclerotic plaque size by regulating inflammation, oxidative stress, intestinal integrity, and intestinal immunity.
The distribution of Sarcocsytis species described by ungulates-canids life cycle in intestines of small predators of the family Mustelidae
Authors: Sneideris Donatas , Moskaliova Darija , Butkauskas Dalius , Prakas Petras
Published: October 2023

Purpose
Using molecular techniques, we have previously shown that carnivorous mammals of the family Mustelidae might be common definitive hosts for various protozoan Sarcocystis species. In the present study we aimed to unravel whether Sarcocystisspecies using ungulates as intermediate hosts and canids or felids as definitive hosts can be found in intestine of mustelids.
Methods
Small intestine samples of 93 individual mustelids of five different species from Lithuania were examined. Sarcocystis species were identified based on species-specific PCR and subsequent cox1 sequencing.
Results
Six Sarcocystis species (S. arieticanis, S. bertrami, S. capracanis, S. capreolicanis, S. linearis and S. morae) defined by ungulate-canid life cycle were detected for the first time in small intestines of mustelids. By contrast, the prevalence of Sarcocystis characterised by ungulate-felid life cycle was low (3.2 %). Overall, 76 % of the examined animals were positive for at least one of the studied Sarcocystis species. Four species, S. arieticanis, S. bertrami, S. capracanis and S. moraewere most commonly found, with the detection rate of about 40 %.
Conclusions
Current finding, in addition to our previous studies, suggests that mustelids play an important role in the spread of various Sarcocystisspecies.
D-cysteine inhibits iron-sulfur cluster assembly and impairs tumour growth
Authors: Martinou Jean-Claude , Zangari Joséphine , Stehling Oliver , Freibert Sven-Andreas , Rouaud Florian , Beinier Veronique Serre , Maundrell Kinsey , Montessuit Sylvie , Ferre Sabrina , Vartholomaiou Evangelia , Schulz Vinzent , Zuhra Karim , González-Ruiz Víctor , Hanschke Sarah , Tsukamoto Takashi , Szabo Csaba , Rudaz Serge , Boniecki Michal , Cygler Miroslaw , Lill Roland
Published: October 2023

Selective targeting of cancer cells is a major challenge for cancer therapy. Many cancer cells overexpress the cystine/glutamate antiporter xCT/CD98 to increase the import of L-cystine for antioxidant defense, thus supporting tumour cell survival and progression1,2. We have exploited this feature of cancer cells by transforming xCT/CD98 overexpression into a selective vulnerability. We found that the D-enantiomer of cysteine (Cys), but not other D-amino acids, impaired proliferation of numerous xCT/CD98-expressing cancer cell lines, whereas xCT/CD98-non-overexpressing (cancer) cells were unaffected. D-Cys acquired by xCT/CD98 specifically inhibited the cysteine desulfurase NFS1, the sulfur donor of cellular iron-sulfur protein biogenesis3. NFS1 was able to form the D-Cys-ketimine intermediate, but, due to steric incompatibility, failed to transfer the D-Cys sulfur to its active-site Cys381 residue, thereby blocking enzymatic activity. This led to a general defect of all cellular processes relying on iron-sulfur proteins, including mitochondrial respiration, nucleotide metabolism, and nuclear genome maintenance, resulting in reduced oxygen consumption, accumulation of DNA damage, and cell cycle arrest. In vivo D-Cys administration diminished tumour growth of human triple-negative breast cancer cells implanted orthotopically into the mouse mammary gland. Hence, D-Cys could represent a simple therapy to selectively target those forms of cancer characterized by overexpression of xCT/CD98.
A novel hybrid model for hourly streamflow and water level prediction from radar reflectivity using deep learning approaches
Authors: Dinh Thi-Linh , Phung Dai-Khanh , Kwon Hyun-Han , Bae Deg-Hyo
Published: October 2023

Urban flooding has become an important challenge for metropolitan areas; thus, reliable water level and streamflow predictive models are crucial to flood control and planning. In this study, we develop a hybrid model, namely SGGP, for hourly water level and streamflow predictions in the Jungrang urban basin, located on the Han River, South Korea. This model includes two sub-models in which the first model is established for producing three-hour mean areal precipitation (MAP) from quantitative precipitation forecasts (QPFs) based on the Spatial-scale Decomposition method (SCDM) using Gate Recurrent Units (GRU), and the second model is utilized to predict hourly-ahead water level and streamflow by integrating a GRU with a particle swarm optimization (PSO) algorithm. The radar data, rainfall, water level, and streamflow data were collected from 2008 to 2022, and are used to establish and evaluate the performance of the model. The SGGP model is evaluated using root mean square error (RMSE), correlation coefficient (CC), mean absolute error (MAE), Nash-Sutcliffe efficiency (NSE), and mean absolute percentage error (MAPE) in comparison with four other deep learning models. The results show that the proposed SGGP model achieves accurate results in multistep-ahead water level and streamflow predictions.
Exploring Strategies, Programs, and Influencing Factors for Integrating Social Accountability into Undergraduate Medical Education: A Scoping Review
Authors: Abdalla Mohamed Elhassan , Taha Mohamed H. , Onchonga David , Nour Nehal , Kelly Dervla , Harney Sarah , McGrath Deirdre
Published: October 2023

Background: Social accountability (SA) measures institutional responses to societal needs. For medical education to be socially accountable, institutions must be equitably accessible and commit to training physicians who can work with communities to address health disparities. This scoping review aimed to explore the integration of social accountability into undergraduate medical education and examine the various ways it is implemented.
Methods: The authors searched PubMed, OVID Medline, CINAHL, ERIC and Scopus electronic databases for articles published between January 1995 and June 2023 to explore how SA is integrated into undergraduate medical education. The enhanced version of Arksey's and O'Malley's six-stage protocol was used. Analysis was done using the thematic analysis approach.
Results: 826 articles were retrieved in the preliminary search. After the screening, 17 articles were included for final review. From the findings, three thematic areas were derived, which included strategies applied in incorporating SA into undergraduate medical education, factors influencing the adoption of SA into undergraduate medical education, and programmes used to translate SA into undergraduate medical education.
Conclusion: This scoping review provides a comprehensive overview of the strategies, programs, and influencing factors related to the integration of social accountability into undergraduate medical education. The implementation of SA in undergraduate medical education is still very slow across the globe, there is an urgent need for a continued push towards making medical schools socially accountable.
Coniacian facies and environments of the Iberian basin: Evolution, and the problem of the facies mixing with implications for basin paleogeography and paleoceanography
Authors: García-Hidalgo José F. , Gil-Gil Javier , Bretones Antonio , Boix Carme
Published: October 2023

The Coniacian carbonate sediments of the Iberian basin were deposited in a homoclinal ramp grading upwards to a distally-steepened ramp, with a major coastal siliciclastic fringe. Twenty-four facies were recognized and grouped into four main depositional environments: outer, mid, inner ramp (including shoal and lagoon subenvironments), and coastal (with carbonate tidal-flat and siliciclastic coastal subenvironments). The more outstanding biogenic components show a mixture of sunlight-dependent, phototrophic, organisms (mainly large benthic foraminifera) and nutrient-dependent, heterotrophic, organisms (mainly rudists), being remarkable the scarce presence of corals; nutrients supplied from the emerged mainland were probably a source for the development of heterozoan organisms. Three main stages of the ramp evolution were: (1) narrow homoclinal ramp with a fringe of coastal siliciclastic sedimentation; (2) drowning and outer ramp widening with siliciclastic sedimentation; and (3) distally steepened ramp with facies aggradation and progradation of the mid and inner ramp sediments. Siliciclastic distribution is problematic since the sands sourced to the basin should have been rapidly and widely redistributed along the basin considering the common storm, wave, and tidal processes shown by the sedimentary facies. The presence of a clockwise NW-flowing longshore current is necessarily assumed to originate such distribution, which was probably induced by dominant external currents around Iberia. These clockwise gyres facilitated the larval dispersion to this enclosed basin and the local presence of upwelling influences; that could have been another source of episodic nutrient-rich waters from the deep ramp, which consequently favored heterozoan development even in the more proximal and relatively shallower facies.