bluuebunny/crossref_metadata_2025 huggingface dataset:
Does the esv3587290 Copy-Number Variation in the VANGL1 Gene Differ as a Genetic Factor for Developing Nephritis in Mexican Childhood-Onset Systemic Lupus Erythematosus Patients?
Authors: ALCÁNTARA-ORTIGOZA MIGUEL ANGEL , Rodríguez-Lozano Ana Luisa , Estandía-Ortega Bernardette , González-del Angel Ariadna , Díaz-García Luisa , Rivas-Larrauri Francisco Eduardo , Nájera-Velázquez Ruth Guadalupe
Published: June 2024

A ~3-kb deletion-type DNA copy-number variation (CNV, esv3587290) located at intron 7 of the VANGL1 gene (1p13.1, MIM*610132) has been proposed as a genetic factor for developing lupus nephritis (LN) in adult systemic lupus erythematosus (SLE) patients across European-descent populations, but its replication in other ethnicities has been inconsistent and its association with LN in childhood-onset SLE (cSLE) remains unknown. Here, we performed an exploratory association study in a sample of 66 unrelated cSLE Mexican patients (11 males, 55 females; ages 7.8 to 18.6 years). Two stratified groups were compared: cSLE patients with (N=39) or without (N=27) LN, as diagnosed by renal biopsy (N=17), proteinuria (N=33), urinary protein:creatinine ratio >0.2 (N=34), and erythrocyturia and/or granular casts in urinary sediment (N=16). For esv3587290 CNV genotyping, we performed an end-point PCR assay with breakpoint confirmation by Sanger sequencing. We also determined the allelic frequencies of the esv3587290 CNV in 181 deidentified ethnically-matched individuals (reference group). The obtained genotypes were tested for Hardy-Weinberg equilibrium (HWE) by c2 test. Associations between LN and esv3587290 CNV were tested by calculating the Odds Ratio (OR) and using Pearson's c2 tests with a 95% confidence interval and P≤0.05. The esv3587290 CNV allele (OR 0.108, 95% CI 0.034-0.33, P=0.00003) and the heterozygous genotype (OR 0.04, 95% CI 0.119-0.9811, P=0.002) showed a significant protective effect against LN development. Finally, we characterized the precise breakpoint of the esv3587290 CNV as NG_016548.1(NM_138959.3):c.1314+1339_1315-897del (https://databases.lovd.nl/shared/variants/0000918418#00025811) in our population. This report supports the notion that a broad genetic heterogeneity underlies the susceptibility for developing LN.
Metabolic Control of Sugarcane Internode Elongation and Sucrose Accumulation
Authors: Botha Frederik , Marquardt Annelie
Published: June 2024

The relationship between metabolic changes occurring in the developing internodes of sugarcane and the final yield and sugar characteristics is poorly understood. This is due to the lack of integration between phenotypic and metabolic data. To address this issue, a study was conducted where sugarcane metabolism was modelled based on the measurement of cellular components in the top internodes at two stages of crop development. The study also looked at the effects of Trinexapac-ethyl (Moddus®) on growth inhibition. The metabolome was measured using GC-analysis while LC-MS/MS was used to measure proteome changes in the developing internodes. The data was then integrated with the metabolic rates. The study revealed that the duration of internode growth is independent of the growth rate and is probably controlled by the accumulation of heat units (degree days). In contrast, sucrose and lignin accumulation is sensitive to the growth rate. Sucrose accumulation only occurs once the cell wall synthesis slow down. The data suggest that sucrose accumulation is controlled a reduction in sucrose breakdown for metabolic activity and a reduction in demand for carbon for cell wall polysaccharide synthesis. This study also found that nucleotide sugar metabolism appears to be a key regulator in regulating carbon flow during internode development.
Piezoelectric Micromachined Microphone with High Acoustic Overload Point and with Electrically Controlled Sensitivity
Authors: Rufer Libor , Esteves Josué , Ekeom Didace , Basrour Skandar
Published: June 2024

Nowadays, the most advanced micromachined microphones on the market are based on a capacitive coupling principle. Capacitive micro-electro-mechanical systems-based (MEMS) microphones resemble their millimetric counterparts, both in function and in performances. The most advanced MEMS microphones reached a competitive level compared to commonly used measuring microphones in most of the key performance parameters except the acoustic overload point (AOP). In an effort to find a solution for measurement of high-level acoustic fields, microphones with piezoelectric coupling principle have been proposed. Such novel microphones exploit the piezoelectric effect of a thin layer of aluminum nitride, which is incorporated in their diaphragm structure. In these microphones fabricated with micromachining technology, no fixed electrode is necessary, in contrast to capacitive microphones. This specificity significantly simplifies both the design and the fabrication and opens the door for a new improvement of the acoustic overload point as well as harsh environmental applications. Several variations of piezoelectric structures together with an idea leading to electrically controlled sensitivity of MEMS piezoelectric microphone are discussed in the paper.
Indistinguishability Hypothesis for Temporarily Identical Particles and Its Possible Implications
Authors: Li Jianfeng
Published: June 2024

Particles are considered temporarily identical if the interchange of these particles does not cause any observable physical effects within a time interval Δt. An indistinguishability hypothesis is proposed for such particles, suggesting that two particles (or systems) with nearly the same degree of internal freedom will actually interchange under certain circumstances, thereby affecting the subsequent dynamics. This indistinguishability implies that, theoretically, it is possible to capture an elementary particle with extraordinarily large internal freedom by trading it for an isolated composite system of ordinary matter particles with almost the same total internal freedom as the large-freedom particle. Following this, the ordinary particles will instantly disperse into the environment, while the large-freedom particle will initially be captured and then gradually delocalized into the environment, an observable phenomenon. If this hypothesis is proven true in the future, it might provide a novel strategy for detecting dark matter particles.
Beccak: Combination of Blockchain and Keccak Algorithm for Improved Digital Signature Performace
Authors: Darmawan Irfan , Maulana Firman , Rahmatulloh Alam , Gunawan Rohmat
Published: June 2024

Data integrity and security are among the most essential things in this digital era performance. Digital certificates can be one solution to this problem. This research will develop the architecture of digital certificate verification and validation using blockchain. The blockchain concept for digital certificates uses three stages: requirements planning, workshop design, and implementation. Digital certificate files will be tested based on a scenario in which there could be any changes to those files, such as compressing files, changing data of files, inserting images in the file, and rotating files. This system architecture will detect any changes that could occur to the digital certificate file by using a digital signature, Keccak256 hash algorithm, and blockchain. This research shows that change detection accuracy for digital certificate files is 100%. However, there is a digital signature nature that could reduce the accuracy of change detection, and several solutions can be resolved. The average time to generate a signature using blockchain technology is 2.11 seconds, faster than 3.23 seconds when it does not use blockchain. The average time to validate a signature is 2.11 seconds without using blockchain, which is reduced to 0.22 seconds using blockchain technology. This research concludes that the architecture for digital certificate verification and validation using blockchain technology has successfully improved the security of digital certificates. Testing showed that even minor changes to a digital certificate could affect the signature, ensuring the certificate's integrity. For further research, evaluating the performance of various hash algorithms within the blockchain network is recommended.
Dynamical Behaviors of a Stochastic SITRS Cholera Model With Ornstein-Uhlenbeck Process
Authors: Li Shenxing , Li Wenhe
Published: June 2024

In this study, a cholera infection model with the bilinear infection rate is developed by considering the perturbation of the infection rate by the mean-reverting process. First of all, we give the existence of a globally unique positive solution for a stochastic system at arbitrary initial value. On this basis, the sufficient condition for the model to have an ergodic stationary distribution is given by constructing proper Lyapunov functions and tight sets. This indicates in a biological sense the long-term persistence of cholera infection. Furthermore, after transforming the stochastic model to an relevant linearised system, an accurate expression for the probability density function of the stochastic model around a quasi-endemic equilibrium is derived. Subsequently, the sufficient condition to make the disease extinct is also derived. Eventually, the theoretical findings are shown by numerical simulations. Numerical simulations show that the impact of regression speed and fluctuation intensity on stochastic systems.
Causal Extraction to Measure Media Bias? A Comparative Analysis of Causal Attributions in Reporting of the Israel-Palestine Conflict
Authors: Béchara Hannah , Corral Paulina Garcia , Jankin Slava
Published: June 2024

Causal language can be a powerful tool for media outlets to subtly influence public perception and reinforce specific narratives. Therefore, identifying these linguistic patterns can be helpful in assessing the level of bias present in media content. In this paper, we directly compare the prevalence of causal language in headlines pertaining to the coverage of the Israel-Palestine conflict and the Russia-Ukraine war. We specifically look at the BBC and AlJazeera headlines covering the assault on Gaza since October 7, 2023. We use UniCausal, a model for causal text mining, in order to automatically extract the cause and effect of each headline. Our findings reveal that BBC headlines tend to avoid directly attributing causality to Israel for the violence in Gaza, whereas Al Jazeera headlines explicitly identify Israel as the responsible party. This differential use of causal language suggests a potential bias in media reporting.
Multi-antenna Arrays Based Massive-MIMO for B5G/6G: State-of-the-Art, Challenges and Future Research Directions
Authors: Qamar Faizan , Kazmi Syed Hussain Ali , Ariffin Khairul Akram Zainol , Tayyab Muhammad , Nguyen Quang Ngoc
Published: June 2024

This comprehensive article explores Massive MIMO (M-MIMO) design and its associated concepts, focusing on the seamless integration requirements for Beyond 5G (B5G) and 6G networks. Addressing critical aspects such as RF chain reduction, pilot contamination, Cell-Free MIMO, and security considerations, the article delves into the intricacies of M-MIMO in the evolving landscape of B5G. Moreover, the emerging MIMO concepts in this article include AI-enabled M-MIMO three-dimensional beamforming, reconfigurable intelligent surfaces, visible light communication, and THz spectrum utilization. This review highlights challenges and open research issues, including Narrow Aperture Antenna Nodes, Plasmonic Antenna Arrays, Integrated Sensing with M-MIMO, and the application of Federated Learning in M-MIMO systems. By examining these cutting-edge developments, the article aims to contribute to advancing knowledge in the field and inspire future research directions in the exciting realm of B5G and 6G networks.
Time-Delay Dynamic Model and Cost-Effectiveness Analysis of Major Emergent Infectious Diseases with Transportation-Related Infections and Entry-Exit Screening
Authors: Xie Yi , Zhang Ziheng , Wu Yan , Li Shuang , Pang Liuyong , Li Yong
Published: June 2024

We analyze a time-delayed SIQR model that considers the transportation-related infections and entry-exit screening. This model aims to determine the measures for preventing and controlling major emergent infectious diseases and the associated costs. We calculate the basic reproduction number (R0), apply the linearization method, and construct an appropriate Lyapunov function to determine the stability of the disease-free equilibrium in the local and global. We collect COVID-19 infection data from two regions in the United States in 2020 for data fitting, obtain a set of optimal parameter values, and show that the model is suitable for simulating the outbreak and spread of emerging infectious diseases. We find that transportation-related infections increase the basic reproduction number, enhancing the impact on disease spread. Entry-exit screening effectively suppress the spread of disease by reducing the basic reproduction number. Furthermore, we investigate the influence of the incubation period on disease and find that a shorter incubation period results in a shorter duration but a larger scale of infection, and the peaks are reduced. We conduct a sensitivity analysis of the R0 and propose three measures to prevent the spread of new infectious diseases based on the most sensitive parameters: wearing masks, implementing urban closures, and administering medication to sick but not yet hospitalized patients promptly. In the case of COVID-19, we use Pontryagin’s minimum principle to get time-varying control measures to control the spread of the outbreak. Optimal control effectively controls the development and deterioration of the disease. Finally, several control measures are compared through cost-effectiveness analysis, and the results show that wearing masks is the most cost-effective measure. Our study provides some practical guidance for controlling the spread of major emerging infectious diseases.
Research of Large Inflow Angles BEMT-Based Analytical-Numerical Performance Evaluation Model
Authors: Sosa Henríquez Carlos , Lendraitis Martynas
Published: June 2024

This paper presents a comprehensive analytical-numerical algorithm constructed for proprotor performance evaluation, focusing on accommodating large inflow angles. The algorithm’s design, range, and analytical features are clarified, indicating its potential to improve performance analysis, particularly for blades with substantial pitch variations. The Stahlhut model has not been validated against the conventional BEMT small-inflow angle methodology. This paper implements a modified Stahlhut model, coupled with the conventional BEMT theory. Preliminary validations of the model demonstrate promising results, with deviations reduced to -3% to 4% compared to conventional BEMT methods exhibiting deviations as high as 20% to 88% against experimental data for a highly twisted proprotor. The reconsideration of the computational module carries considerable implications for the design and refinement of proprotors, providing alternative analysis methods that could improve operational effectiveness across a range of flight scenarios. Drawing upon the theoretical framework presented by Stahlhut, the algorithm enables a more complex understanding of proprotor dynamics, facilitating accurate predictions of the loads at each blade section. The introduced algorithm emerges as a valuable asset for evaluating proprotor performance during the early stages of design and certification, offering both low computational cost and medium to high reliability.
“I Have Never Visited a Health Center:” Ethiopian Centenarians’ Perceptions of Their Health Conditions
Authors: Chane Samson , Adamek Margaret E.
Published: June 2024

The global centenarian population is expected to reach 3 million by 2050, yet little is known about the health status of centenarians in Sub-Saharan Africa. A case study examined the health conditions and functionality of nine Ethiopian centenarians. In-depth interviews revealed that all nine were Orthodox-Christians and lived with extended family; eight were male. Aside from minor health complaints, centenarians in rural Ethiopia perceived that their sensory/cognitive functionality was normal until their late 90s. Despite a lack of medical care, the centenarians included 2 survivors, 4 delayers, and 3 escapers. Centenarians in rural Ethiopia were embedded in closely-knit, religious, multigenerational households and communities and aspired to live resiliently. Findings call for consideration of the unique health status of centenarians in Global South nations in their own cultural context.
The Influence of Cultural Factors on Supply Chain Integration in Multinational Corporations
Authors: Reynolds Samantha
Published: June 2024

In today's globalized business environment, multinational corporations (MNCs) face significant challenges in achieving and sustaining effective supply chain integration across diverse cultural contexts. This qualitative research explores the influence of cultural factors on supply chain integration within MNCs, employing in-depth interviews and thematic analysis to uncover key insights. Findings reveal the complex interplay between culture and supply chain practices, highlighting challenges related to cross-cultural communication, trust-building, decision-making, and organizational culture alignment. However, the study also identifies opportunities for leveraging cultural diversity as a source of competitive advantage, emphasizing the importance of cultural intelligence and cross-cultural competence for supply chain professionals. The implications of the research extend to managerial practice, suggesting the development of culturally sensitive strategies for supply chain integration and investment in cultural training and development programs. Moreover, the study underscores the need for a holistic approach to supply chain integration that considers not only technical and operational aspects but also cultural and social dimensions. While the research offers valuable insights, limitations such as the qualitative nature of the study and the focus on supply chain managers' perspectives should be considered. Future research could address these limitations and explore the interdependencies among various contextual factors to enhance our understanding of cultural influences on supply chain integration in MNCs.
Control System Modification of a 5-kW Pellet Stove: Study and Analysis
Authors: Álvarez-Murillo Andrés , González González Juan Félix , Piquer Carapeto Javier , Nogales-Delgado Sergio
Published: June 2024

The use of sustainable energy sources is a feasible alternative for fossil fuel products, which can represent a positive factor to alleviate many current environmental issues. In that sense, not only the sustainable industrial development is important, but also sustainable practices at local level, including households. Specifically, heating and cooking are one of the most important activities that require energy in households, where the role of biomass could be interesting, as it can provide an energy source with lower environmental impact. However, there is room for improvement in biomass stoves, whose adaptability to specific wastes, as well as their improvement in efficiency, should be accomplished. The aim of this work was to assess the improvement of combustion performance of a domestic stove by the implementation of a programmable logic converter for a better adaptation to different biomass samples (holm oak, pear tree, poplar and sugarcane bagasse pellets). Thus, the working regime of the stove was controlled, especially concerning the screw conveyor (to regulate pellet feeding) and flue gas fan (to change oxygen supply). As a result, better combustion performances were obtained, heat capacities from 5.66 to 8.67 kW for the selected samples. On the other hand, different improvements of the combustion stove to avoid blockages, for instance, are proposed as further steps.
Application of a Laser Profile Sensor for the Full Field Measurement of the Continuous Icing Process of Rotating Blades
Authors: Filippatos Angelos , Schwab Simon , Wollmann Tino , Gude Maik
Published: June 2024

With the advancing energy transition, ice is a growing problem in wind turbine sector. The development of systems to detect and mitigate icing makes it necessary to understand its basic behavior and characteristics. This paper proposes a method for the continuous and full field measurement of the icing process of rotating blades, using a single line laser profile scanner. Inside of a climate chamber, a rotor is driven by a motor, while a system of nozzles provides a fine water dust, which leads to ice accumulating on simple NACA blades, that in turn is measured by a triangulation laser. The measurement data is cleared from outliers and presented as a surface in 3D space. An alpha shape is used to reconstruct and extract the volume of the ice between a reference and a measurement surface, using the corresponding Matlab function. Appropriate input parameters for the function and offsetting of the reference surface to improve the results are compared and discussed. The resulting system is able to detect thin changes in the ice layer in the range of sub millimeter thickness.
Amelioration of Photoreceptor Degeneration by Intravitreal Transplantation of Retinal Progenitor Cells in Rats
Authors: Yang Jing , Lewis Geoffrey , Hsiang Chin-Hui , Menges Steven , Luna Gabriel , Cho William , Turovets Nikolay , Fisher Steven , Klassen Henry
Published: June 2024

Photoreceptor degeneration is a major cause of untreatable blindness worldwide and has recently been targeted by emerging technologies, including cell- and gene-based therapies. Cell types of neural lineage have shown promise for replacing either photoreceptors or retinal pigment epithelial cells following delivery to the subretinal space, while cells of bone marrow lineage have been tested for retinal trophic effects following delivery to the vitreous cavity. Here we explore an alternate approach in which cells from the immature neural retinal are delivered to the vitreous cavity with the goal of providing trophic support for degenerating photoreceptors. Rat and human retinal progenitor cells were transplanted to the vitreous of rats with a well-studied photoreceptor dystrophy, resulting in substantial anatomical preservation and functional rescue of vision. This work provides scientific proof-of-principle for a novel therapeutic approach to photoreceptor degeneration that is currently being evaluated in clinical trials.
Analyzing the Shortcomings in Smart Healthcare for Remote Home Care—A Case Study of the Taiwan Market
Authors: Yang Yunqi , Lin Grace.T.R
Published: June 2024

In Taiwan, remote healthcare was initially limited to telemedicine services, and the systematic development of remote care was relatively delayed. It was not until 2007 that the Department of Health of the Executive Yuan first initiated the 'Remote Care Pilot Program,' followed by the 'Remote Care Service Improvement and Quality Enhancement Plan' in the subsequent year. In 2010, Taiwan officially launched the 'Remote Health Care Services Development Plan' and established a dedicated project office, marking the comprehensive start-up of remote care services. This stage saw significant contributions from artificial intelligence aids and ICT remote transmission technologies, greatly promoting the application of smart healthcare in home care. This study aims to explore the strategic gaps in the application of smart healthcare in home remote care. By analyzing gaps in 'legal regulations,' 'economic factors,' 'user behavior habits,' 'policy and culture,' and 'environment and technology,' this study employs a mixed-methods approach. Particularly, it uses the Analytic Hierarchy Process (AHP) to construct a weighted ranking of these strategic gaps. Through in-depth interviews with doctors and smart healthcare experts and the collection of 16 valid AHP questionnaire samples, which cover both industry and academia with a balanced distribution, the survey results are ensured to be representative and reliable. The findings indicate that 'legal regulations' are considered the most critical strategic gap that needs to be addressed first, followed by 'user behavior habits.' This suggests that when designing smart healthcare applications, greater consideration needs to be given to user acceptance and habits. By systematically analyzing and addressing these strategic gaps, this study not only provides solutions to issues in the application of smart healthcare in home remote care but also offers valuable references for future research and practice, aiming to make home remote care services more comprehensive and efficient.
A Study on Possibility of Detrimental Effects of Soil-Structure Interaction in Seismic Design Due to a Shift of System Frequency
Authors: Tao Weifeng , Fu Jia , Li Yugang
Published: June 2024

Soil-structure interaction (SSI) leads to a modification of dynamic properties of a structure, but due to the complexity on analysis, it is traditionally assumed in seismic designs that the structure is fixed-supported at the ground, which unavoidably gives potential dangers to seismic performances of the structure. This study focuses on the possibility of the detrimental effects of SSI by comparing the dynamic responses of SSI system to fixed-base structure. The SSI model consists of an oscillator, a three-dimensional foundation and a multilayered half-space. In indirect boundary element method is employed, combined with non-singular Green’s functions of distributed loads to calculate the foundation impedances for substructure method. Although the SSI mechanism dampens peak amplitude of structure response in frequency domain, case studies on four buildings to 42 earthquakes in time history show a possibility of 15%-20% that SSI amplifies the dynamic responses, depending on the frequency component of incident waves. Also, a neural network algorithm is proposed to provide a new idea of involving SSI analysis into the traditional seismic designs, to eliminate potential hazards of SSI.
Exploring the Evolutionary Basis and Population Genetics of ADHD
Authors: Montgomery Richard Murdoch
Published: June 2024

Attention-Deficit/Hyperactivity Disorder (ADHD) exhibits a notable prevalence across diverse populations, with estimates ranging from 4% to 6%. This wide range prompts an investigation into the evolutionary and genetic underpinnings of ADHD, especially considering the markedly different environments faced by ancestral human populations compared to today's structured societies. This study examines the potential adaptive advantages of ADHD-associated traits in hunter-gatherer contexts, where hyperactivity, impulsivity, and novelty-seeking behaviors may have conferred survival benefits. We employ the principles of population genetics, including Hardy-Weinberg equilibrium, selection coefficients, and genetic drift, to model the dynamics of ADHD allele frequencies over time. Additionally, we discuss balancing selection as a mechanism for maintaining genetic diversity and how gene-environment interactions (GxE) contribute to the expression of ADHD in contemporary settings. Our analysis suggests that traits associated with ADHD, while potentially maladaptive in modern structured environments, could have been preserved through evolutionary processes due to their adaptive value in ancestral contexts. Understanding these dynamics provides a comprehensive view of ADHD's prevalence and highlights the significance of genetic and environmental interplay in shaping human behavior.
Laplace-Logistic Unit Distribution with Application in Dynamic and Regression Analysis
Authors: Stojanović Vladica S. , Jovanović Spasojević Tanja , Jovanović Mihailo
Published: June 2024

This manuscript presents a new two-parameter unit stochastic distribution, obtained by transforming the Laplace distribution, using generalized logistic map, into a unit interval. The distribution thus obtained is named the Laplace-logistic unit (abbreviated LLU) distribution, and its basic stochastic properties are examined in detail. Also, the procedure for estimating parameters based on quantiles is provided, along with the asymptotic properties of the obtained estimates and the appropriate numerical simulation study. Finally, the application of the LLU distribution in dynamic and regression analysis of real-world data with accentuated "peaks" and "fat" tails is also discussed.
Porvac® Subunit Vaccine Confers Full Protection against Three Field Isolates of Classical Swine Fever Virus
Authors: Sordo-Puga Yusmel , Rodríguez-Moltó María Pilar , Pérez-Pérez Danny , Naranjo Valdéz Paula , Sardina González Talia , Mendez Orta Mary Karla , Santana-Rodríguez Elaine , Vargas-Hernández Milagros , Laura Perera Carmen , Duarte Carlos A. , Suárez Pedroso Marisela
Published: June 2024

The control of classical swine fever (CSF) in endemic areas has been attempted with modified live vaccines. However, in some regions, the implementation of imperfect vaccination programs has led to a reduction in the genetic diversity of the circulating strains and a change in their virulence. Porvac® subunit vaccine has been shown to provide a rapid onset of protection against the “Margarita” strain. The aim of this study was to evaluate whether the immune response induced by Porvac® is also effective against autochthonous isolates of low, medium or high virulence. All pigs vaccinated with Porvac® were protected against the disease after the challenge. PR-11/10–3 isolate caused a very mild disease in controls, whilst Holguin_2009 isolate produced mild to moderate signs of CSF and one of the pigs died. Finally, controls inoculated with PR-2016 isolate developed moderate to severe signs of CSF and two of them died. Viral replication was detected in controls, but not in pigs immunized with Porvac®. Finally, anti-Erns antibodies were induced in five out of six control pigs but in any of the vaccinated pigs. These results support the use of Porvac® for the control and elimination of CSF in Cuba and other endemic regions.
Modelling of Granular Sediment Transport in Steady Flow Over a Mobile Sloped Bed
Authors: Biegowski Jarosław , Pietrzak Magdalena , Radosz Iwona , Kaczmarek Leszek M.
Published: June 2024

This paper introduces a three-layer system, proposing a comprehensive model of granular mixture transport over a mobile sloped bed in a steady flow. This system, consisting of the bottom, contact and upper zones, provides complete, continuous sediment velocity and concentration vertical profiles. The model considers gravity’s effect on sediment transport in the bottom (dense) layer, a crucial factor often overlooked in previous studies. The induced movement in the mobile sublayer of the dense layer causes an increase in velocity at the upper boundary of this layer, significantly affecting the vertical distributions of velocity and concentration above this layer. We described the interactions between fractions and an intensive sediment mixing and sorting process in the contact layer. The proposed shear variation, with an increase in its maximum value at the bed, adds to the novelty of our approach. The data sets used for the model’s validation cover various conditions, including slopes, grain diameters, densities and grain mobility conditions, from incipient motion to a fully mobilised bed. This extensive validation process instils confidence in the theoretical description and its applicability to real-world scenarios.
ENSURING THE FUNCTIONAL STABILITY OF THE INFORMATION SYSTEM OF THE POWER PLANT ON THE BASIS OF MONITORING THE PARAMETERS OF THE WORKING CONDITION OF COMPUTER DEVICES
Authors: Barabash Oleg , Svynchuk Olha , Salanda Ivanna , Mashkov Viktor , Myroniuk Mykola
Published: June 2024

The functional stability of the information system of the power plant is ensured by a complex of processes and mechanisms that are capable of maintaining the normal operation of the system even in the event of errors, failures or negative impacts. The aim of the research. An important aspect of ensuring the functional stability of an information system is the monitoring of its healthy state, as it helps to identify, analyze and respond to any problems in a timely manner, ensuring the reliable and uninterrupted operation of the system. It was decided to choose a test diagnosis based on the principle of a wandering diagnostic core. Research results. An algorithm for detecting failures in the system has been developed based on the decryption of the totality of the results of the system's test checks. The developed software application allows you to monitor the state of various components of the information system and detect possible problems or failures in a timely manner in order to support the continuous operation of the system. This application allows you to increase the reliability of diagnostics, reduce the time of diagnostics, and carry out diagnostics with the specified completeness and depth. The depth and completeness of diagnosis is determined by the test task. Verification. To confirm the correctness of the developed software product, mathematical modeling of the process of diagnosing the information system, which was divided into several subsystems containing a certain number of modules, was carried out. For the division into subsystems, the number of modules in each subsystem is important - it should not exceed 30 modules. This limitation is due to the limited computing power of modern microprocessor technology during the solution of a class of NP-complete problems.
Pediatric Device Innovation
Authors: Dubin Jonathan , Sardesai Krish , Grote Caleb , Tougas Caroline , Branche Katherine , Otsuka Norman
Published: June 2024

Background:

Despite a tremendous increase in the number of orthopaedic devices authorized by the U.S. Food and Drug Administration (FDA), novel devices designed specifically for the pediatric population remain sparse. Surgeons frequently repurpose adult implants for “off-label” use in pediatric patients, with both legal and technical ramifications. This study seeks to objectively quantify and characterize the nature of pediatric device innovation over time.

Methods:

The FDA employs 4 pathways for assessing safety and effectiveness of novel devices prior to authorization. Perceived device risk and novelty determine the pathway. Orthopaedic devices were identified from the FDA’s online database. All devices approved since inception via the Humanitarian Device Exemption, Pre-Market Approval, and De Novo regulatory pathways were included and grouped as “highly innovative.” Because of their number and the rapidity of their development, the evaluation of 510(k) devices was limited to those cleared from January 1, 2018, to December 31, 2022. Such 510(k) devices make up ∼97% of devices and by definition are less risky and less novel. Approval statements were assessed for pediatric indications within the approved labeling. As a secondary analysis, the impact of company size on developing a product with a pediatric indication was analyzed.

Results:

Of the 1,925 devices cleared via the 510(k) pathway, 9 (0.5%) were designed exclusively for pediatrics and 160 (8.3%) included pediatric indications. Five of the 9 pediatrics-only devices were for spine and 4 were for trauma indications. Of the 97 highly innovative devices, only 2 (2%) were exclusively pediatric and another 2 (2%) included pediatric indications. The 2 pediatrics-only devices were for the spine. Large and medium-sized companies were 1.9 times and 1.6 times more likely to bring to market a device with pediatric indications than a small company, respectively.

Conclusions:

Innovation for pediatric orthopaedic devices lags substantially behind that for adult orthopaedic devices. These findings are consistent with clinical experience and the common practice of modifying adult implants for “off-label” use in pediatric patients. Despite long-standing efforts to stimulate innovation for this vulnerable population, our results suggest little progress.
Determining PID Parameters For Temperature Control System in Cavendish Banana Storage Room
Authors: Arifuddin Rahman , Subairi Subairi , Setiawan Aries Boedi , Ridlo Muhammad Ali , Ziliwu Alsaro Natanael
Published: June 2024

Banana is one of the most popular fruits in Indonesia, and its freshness will be the top priority for consumers in choosing it. After packaging, special treatment needs to be done in the banana storage room. One of them is to keep the temperature of the storage room stable. The temperature of the room between 5oC to 10oC is the ideal temperature for storing bananas, the Control system offered is PID with the Ziegler-Nichols method to get the values of Kp, Ki and Kd. Determination of Kp, Ki and Kd values is very important to get good system stability and a small error. The tuning rule of Ziegler-Nichols 1 method can be applied to obtain the values of Kp, Ki and Kd. With several steps taken, the values of L = 90s and T = 206s are obtained and referring to the Ziegler-Nichols 1 table, the values of Kp = 2.7, Ki = 0.015 and Kd = 121.5 are determined.
Equilibrium Modelling of Interactions in DETPMP-Carbonate System
Authors: Meybodi Mahdi Kalantari , Vazquez Oscar , Sorbie Kenneth S. , Mackay Eric J. , Jarrahian Khosro
Published: June 2024

Scale inhibitor (SI) squeeze treatments are widely used for the prevention of inorganic scale deposition in oil and gas production operations. This may be an expensive operation and its efficiency depends on the degree of SI retention in the formation. Carbonate formations are known to be highly reactive, where the SI retention is driven by both adsorption and precipitation of SI and SI-Ca/Mg complexes. To design and carry out this type of squeeze treatment, a comprehensive model capable of simulating SI retention in carbonate formations is required.

In this study, a model has been developed to fully characterize the retention of DETPMP in a carbonate system. This model considers all the equilibrium reactions coupled with precipitation and adsorption processes to simulate the equilibrium of a DETPMP-Calcite-brine system containing free Ca2+ and Mg2+ cations. To equilibrate this system, the following coupled reactions were considered: (i) the full aqueous carbonate system, (ii) SI speciation by dissociation (SI is considered as a weak n-poly acid, HnA), (iii) SI impurities and their reactions, (iv)SI-Ca and SI-Mg complexation, (v)the associated adsorption and precipitation of the SI/Ca/Mg complexes. These reactions may be coupled together through the equilibrium equations, the mass balance of base species and the system charge balance. After some algebra, the system of equations is reduced and solved by Newton Raphson to find the concentration of key primary species from which the concentration of all other species is calculated and the equilibrium of the entire couple system is characterized. In the entire system, there may be up to ~100 species involved in the chemical equilibrium equation set.

The adsorption process is characterized by an adsorption isotherm, Γ(C), which can be a reversible process. In the examples presented, the adsorption is considered to proceed in both directions of adsorption and desorption. Precipitation (denoted Π) is coupled with the adsorption (and the rest of the system) to satisfy the SI solubility by removing further SI from the solution, if required, through the complex SI species that may physically precipitate.

Finally, the proposed model was validated against coupled adsorption-precipitation experiments. The results showed very good agreement between the model and experiments and confirmed the reliability and validity for various conditions and DETPMP concentrations.
The Formation, Prediction, and Inhibition of CaxFe1-x CO3 in Produced Brine Under High Temperature
Authors: Ye Y. , Wang X. , Shen Y. Y. , Deng G. , Yao X. , Pimentel D. , Kan A. T. , Tomson M. B.
Published: June 2024

This study first measured pure FeCO3 precipitation kinetics from 90 to 150°C (1M NaCl, and pH=6). Then it investigated FeCO3 and CaCO3 precipitation kinetics under the impact of Ca2+ and Fe2+ at 70°C (1M NaCl, and pH=6.17). Overall, the measurement was conducted by using an anoxic flow-through setup with carbon steel surfaces. Key goals included examining the influence of Ca2+ and Fe2+ on precipitation rates, understanding solid solution formation, assessing DTPMP inhibition of CaCO3 precipitation, and confirming the role of mild steel corrosion in scale formation. Results showed that Ca2+ had negligible impact on the FeCO3 precipitation rate but decreased its solubility, Fe2+ accelerated the CaCO3 precipitation and DTPMP inhibited CaCO3 precipitation but caused increased corrosion with amorphous particle formation. Evidence supports the formation of CaxFe1-x CO3 solid solution. Overall, the study enhances understanding of carbonate precipitation dynamics in CO2 corrosion, which is crucial for industrial scale control.
How to Develop a Comprehensive Scale Management Strategy and Use the Scale Risk Factor (SRF) for Chemical Optimisation
Authors: Ness G. , Langvik M. , Ree L. Strand
Published: June 2024

The Valhall field is located in the southern part of the Norwegian sector in the North Sea and has been producing for over 40 years. In more recent years there has been a number of issues caused by the presence of solids in the system and although barite scale was always known to be the main source, a thorough assessment of the problem was required.

A project task force was set up in early 2023 to collate and review years of water chemistry data, solids analysis, Environmental scanning electron microscopy (ESEM), Infrared Thermography reports and other measurements to clearly establish the source of solids in the system and develop a field wide scale prediction model which covers over 60 mixing points from wellhead to water overboard. Thanks to this process the areas at higher risk of scale formation were identified and this provided the basis for scale inhibitor optimisation throughout the system.

In addition to this analysis, a large volume of data that had been stored in various databases was also transferred to Power BI to improve data visualisation and allow faster detection of solids precipitation, easier root cause analysis and ultimately more effective scale management.

Finally, a new calculation was used to quantify the scale risk more holistically and to compare the scaling potential in different parts of the system. This is called Scale Risk Factor (SRF) and is calculated using both Saturation Ratio (SR) and mass of scale predicted. Additional lab work is currently ongoing to produce a trendline which shows how the minimum inhibitor concentration (MIC) for a specific product change with variable SRF.

This case study shows how accurate conventional scale predictions can be used in conjunction with data visualisation and a new parameter, the scale risk factor (SRF) to successfully optimise scale inhibitor injection and potentially reduce operating costs.
Effect of Water Salinity on Barium Sulfate Formation in the Context of Gas Wells in the Dutch Sector of the North Sea
Authors: Doldersum A. , Baraka-Lokmane S.
Published: June 2024

Operator has several gas wells which encountered barium sulfate scale. In one instance this had resulted in a complete blockage of the well and in another well not being able to perform a planned well intervention. This paper will present the investigation of the mechanism of formation of scales in combination with an overview of laboratory and field data on how to treat the barium scales.

The production water of one of the wells is characterised by a very high salinity level close to saturation in combination with presence of barium, strontium, calcium, carbonate, and sulfate. The evaluation of the scaling risk has been carried out from bottomhole to wellhead with commercial software; 80 points modelling have been performed. This has helped to determine the scaling mechanisms for individual scales.

Barium scale from a second well has been used to select an effective dissolvent via laboratory experiments.

The evaluation of the scaling risk has been carried out with a help of a commercial software. The predicted scales are halite, barite, celestite, strontianite and calcite, while mainly barite was found in the recovered deposit. The difference between modelling results and field observation are discussed in the paper.

As halite concentrations exceeded saturation levels, downhole water injection was applied in one of the wells to stay below the saturation levels, due to water evaporation caused by drawdown. However, the reduction of salinity decreases the solubility of barium sulfate which in combination with decreasing temperatures seriously increases the risk of precipitation of barium sulfate. This eventually resulted in a complete blockage of the well.

For the second well, barium scale samples were tested in the laboratory to select the best dissolvent. This dissolvent had been batch injected in the upper part of the well to dissolve the scale. Collected production water at surface immediately after opening of the well, showed increased levels of barium, strontium, and sulfate. Continuous downhole injection of fresh water to compensate for evaporation losses due to drawdown should be carefully evaluated when barium sulfate scaling risk exists as the solubility decreases at lower salinity levels. One of the mitigation methods is therefore to add inhibitors to the injected water.
Case Studies of Novel Seawater-Based FracPac Fluid Used in DeepWater Gulf of Mexico with Barium-Rich Formation Fluids Present
Authors: Slocum Andrew , Yue Zhiwei David , Ke Linping , Thomas Michael , Lacamu Jeremy , Kottemann Matthew , Lizak Ken , Zanten Ryan Van , Lee JiYoung , Karazincir Oya , Marquez Maricel
Published: June 2024

Injecting seawater into producing formations with barium-rich formation water has been avoided for decades due to concerns of barium sulfate scale formation impairing production. The local barium-rich formations unfortunately bring immediate scaling risk due to severe tendencies to form barite when the seawater sulfate contacts barium-rich formation waters. This scaling challenge has driven the industry to utilize freshwater-based fluids for most completions operations which include fracturing and other sand control methods. As multizone completions have increased in frequency over the past decade, the logistical challenges of providing freshwater-based systems have grown greater. To overcome these challenges, a newly developed seawater-based fracturing fluid system has provided benefits over the traditional freshwater-based system.

In this paper, we present case studies of four multizone completions in deepwater Gulf of Mexico which utilized a newly developed seawater-based fracturing fluid integrated with a polymeric scale inhibitor package. All four wells have barium-rich formation waters present and range in temperatures from 194 to 260°F (90 to 127°C). We share the challenges overcome in the designs and operation, field overview data, lab testing results, field deployment results, and initial production results. We also discuss the benefits seen by using seawater-based fracturing fluids for deepwater FracPac jobs to streamline logistics by eliminating the need for supply vessels and reducing cleaning wastes, CO2 emissions and freshwater use.

Unlike proposals in other publications which was characterized by Hou et al. (2023), the seawater based fracturing fluid used on these treatments did not remove the seawater's sulfates by nano-filtration, forced precipitation of sulfates, electrodialysis, or any other means. Sulfate removal techniques were investigated, but currently they are not deemed practical for stimulation vessel use due to the extra equipment requirements and associated processing times.