Modeling Testing Research Articles

Modeling APOE ε4 familial Alzheimer's disease in directly converted 3D brain organoids.

Brain organoids have become a valuable tool for studying human brain development, disease modeling, and drug testing. However, generating brain organoids with mature neurons is time-intensive and often incomplete, limiting their utility in studying age-related neurodegenerative diseases such as Alzheimer's disease (AD). Here, we report the generation of 3D brain organoids from human fibroblasts through direct reprogramming, with simplicity, efficiency, and reduced variability. We also demonstrate that induced brain organoids from APOE ε4 AD patient fibroblasts capture some disease-specific features and pathologies associated with APOE ε4 AD. Moreover, APOE ε4-induced brain organoids with mutant APP overexpression faithfully recapitulate the acceleration of AD-related pathologies, providing a more physiologically relevant and patient-specific model of familial AD. Importantly, transcriptome analysis reveals that gene sets specific to APOE ε4 patient-induced brain organoids are highly similar to those of APOE ε4 post-mortem AD brains. Overall, induced brain organoids from direct reprogramming offer a promising approach for more efficient and controlled studies of neurodegenerative disease modeling.

The Multiple Roles of Structured Multipurpose Databases in Fusion Research

Most databases in fusion research are devoted to a single topic, such as energy confinement, H-modes, profiles, or disruptions. To allow for a wider range of analysis, modeling, and validation tasks, the JETPEAK broad-based multipurpose database has been developed for JET. This database currently includes 27 065 stationary state (∂/∂t ≈ 0) samples and nearly 1000 scalar, one-dimensional (profiles), and two-dimensional (R and Z dependent) variables grouped into topical structures. A similar database has been created for the Tokamak à Configuration Variable (TCV), comprising 65 000 samples reaching back to early TCV operation in the 1990s. The breadth and flexibility of these databases allows them to be used for a wide variety of investigations such as modeling tasks, confinement scaling, testing, validation and benchmarking of algorithms and modeling codes, and long-term monitoring of device conditions, as well as for documentation.

Pengembangan Aplikasi Mobile untuk Peningkatan Layanan Kesehatan di Klinik Menggunakan Metode Waterfall: Studi Kasus Klinik XYZ

In this digital era, patients expect ease of access and transparency in healthcare services. Klinik XYZ, currently using conventional methods, faces challenges in meeting these expectations, such as long queues, incomplete information, and difficulties in scheduling appointments with doctors. This study aims to develop a mobile application to enhance service quality at Klinik XYZ. The method used is Waterfall, involving the stages of needs analysis through observation and interviews, system design, coding, and testing. The findings show that the developed application can provide essential features such as doctor profiles, doctor schedules, appointment scheduling, service selection, ratings, news, and health tips. This application successfully improves the efficiency and quality of services at Klinik XYZ by reducing waiting times and providing a better user experience. The implications of this study indicate that integrating mobile technology into healthcare services can significantly enhance patient satisfaction and the operational effectiveness of the clinic. Arifin, M. N., & Siahaan, D. (2020). Structural and Semantic Similarity Measurement of UML Use Case Diagram. Lontar Komputer : Jurnal Ilmiah Teknologi Informasi, 11(2), 88. https://doi.org/10.24843/lkjiti.2020.v11.i02.p03 Febriyanti, N. M. D., Sudana, A., & ... (2021). Implementasi Black Box Testing pada Sistem Informasi Manajemen Dosen. Jurnal Ilmiah …, 2(3). http://download.garuda.kemdikbud.go.id/article.php?article=3457876&val=30165&title=Implementasi Black Box Testing pada Sistem Informasi Manajemen Dosen Haerani, R., Hendriyati, P., Nugroho, P. A., & Lukman, M. (2023). Waterfall Model Implementation in Information Systems Web Based Goods Delivery Service. JURTEKSI (Jurnal Teknologi Dan Sistem Informasi), 9(3), 501–508. https://doi.org/10.33330/jurteksi.v9i3.2267 Lee Ventola, C. (2014). Mobile devices and apps for health care professionals: Uses and benefits. P and T, 39(5), 356–364. Luxton, D. D., Kayl, R. A., & Mishkind, M. C. (2012). MHealth data security: The need for HIPAA-compliant standardization. Telemedicine and E-Health, 18(4), 284–288. https://doi.org/10.1089/tmj.2011.0180 Martínez-Pérez, B., De La Torre-Díez, I., & López-Coronado, M. (2013). Mobile health applications for the most prevalent conditions by the world health organization: Review and analysis. Journal of Medical Internet Research, 15(6). https://doi.org/10.2196/jmir.2600 Nurbaiti Oktaviani, S., Fikri Aziz, C., & Maula Sulthon, B. (2022). Analisa UI/UX Sistem Informasi Penjualan Berbasis Mobile Menggunakan Metode Prototype. KLIK: Kajian Ilmiah Informatika Dan Komputer, 2(6), 225–233. https://doi.org/10.30865/klik.v2i6.401 Rambe, B. H., Pane, R., Irmayani, D., Nasution, M., Munthe, I. R., Ekonomi, F., & Bisnis, D. (2020). UML Modeling and Black Box Testing Methods in the School Payment Information System. Jurnal Mantik, 4(3), 1634–1640. https://iocscience.org/ejournal/index.php/mantik

Novel Lightweight Hydraulic Integration Methodology for Robotic Applications

Hydraulic integration is one of the novel technologies in the field of robotics and assistive devices. Researchers have applied recent technologies starting from non-conventional machining methodologies and ending with additive manufacturing of metals. However, those methodologies have several drawbacks related to the cost, time, and robot weight. This motivates the research of new methodologies toward developing compact, cost-effective, and lightweight hydraulic integrated robotics mechanisms. This paper presents a novel methodology for fabricating hydraulically integrated parts by using lightweight and high-strength materials. The proposed materials, fabrication steps and the obtained results are thoroughly discussed. Silicon pipes are used for building the network of internal passages. This network is built inside a 3D-printed mould which is designed accordingly. A theoretical study is conducted for the newly manufactured hydraulic parts to define the design parameters and the working pressure at which the manufactured parts can withstand in addition to stresses and deformations analysis. The theoretical results are validated using finite element modelling (FEM) and experimental testing. The simulation results were consistent with the FEM results and the experimental results by 95% and 90% respectively. The proposed methodology is cheap and simple to implement in fabrication. Hence, this methodology can be used to fabricate hydraulic integrated components in hydraulically actuated humanoid robots successfully.

Design of a multichannel vacuum ultraviolet spectroscopy system for SPARC.

The design of a vacuum ultraviolet spectroscopy system has been performed to monitor and provide feedback for impurity control in SPARC. The spectrometer, covering a wavelength range of 10-2000Å through a flat-field configuration with diffraction gratings, incorporates five survey lines of sight. This allows for comprehensive impurity analysis across the core and four divertor regions (inner/outer and upper/lower). Its compact modular design facilitates vertical stacking of each spectrometer unit, significantly reducing space in the tokamak hall, where a dedicated radiation shielding bunker will be built. Safety features include a secondary helium enclosure to mitigate tritium permeation risks during deuterium-tritium (D-T) operations and shielding within the beamlines for enhanced radiation protection. The silicon carbide mirror design for divertor observation ensures its survivability in the in-vessel environment of SPARC, validated by thermal and electromagnetic analysis. Signal modeling and data acquisition testing results show that an exposure time of a few milliseconds is appropriate considering photon flux reaching the detector, demonstrating the system's capability for discharge control that includes disruption avoidance.

Gender, emotional support and innovative behavior: psychological capital as a mediator

PurposeThis paper explores the direct and indirect effects of family emotional, social and organizational support on Innovative Work Behavior (IWB) through psychological capital (Psy.Cap).Design/methodology/approachSelected by conducting stratified random sampling techniques, 397 employees completed a questionnaire. We used structural equation modeling and multi-group testing by Smart-PLS3 to analyze the data.FindingsFindings reveal that all sources of social-emotional support, including family, supervisor and co-worker support, positively affect Psy.Cap. Moreover, Psy.Cap mediates the effect of family, co-workers and supervisors' emotional support on IWB. The multi-group analysis indicates that all relationships in the model are significant for both groups of males and females; however, there are no significant differences in the link between organizational support and psychological capital, as well as family and co-worker support and innovative work behavior between males and females. The study's results demonstrate the significantly higher impact of family emotional support – Psy.Cap and supervisor support on IWB amongst females compared to their male counterparts.Originality/valueThe implications of this research highlight the importance of considering affective factors on employees’ IWB, as well as the differences between genders in this regard.

Weld-joint design to optimize groove weld depth and mechanical properties for welding of nozzle onto pressure vessel

Full and partial set-in weld-joints connect the nozzle to pressure vessels to prevent lamellar tearing. This investigation aims to compare full and partial set-in weld-joints through computer simulations, numerical modelling, welding experiments, nondestructive examination and destructive testing. The nozzle-to-shell opening connection’s weld-joint design model is DN20, with a 50 mm shell wall thickness. The optimal groove weld depth, at a safety factor of 3.5, ranges from 20 to 50 mm. We investigated weld-joint design variations using design-of-experiment, which included actual welding and mechanical testing. The inter-run temperature and its interaction with the heat input were found to be statistically significant. The mechanical properties of welded joint are better than those of the specified material, A516 Grade 70, which include an average impact toughness of 89.5 J at -50 °C, a microhardness of 195 Hv10, an ultimate tensile strength of 533 MPa, a yield strength of 391.5 MPa and an elongation of 56.5%. The coefficients of determination of impact toughness and microhardness, which have R2 values of 88.73% and 76.65%, respectively, conclude a successful welding experiment. The design and mechanical testing results conclude the reliability of the weld-joints.

Finite element modeling and modal testing of a wind turbine lattice tower component with interference pin connections

Fatigue failures at fastener holes in structures are undesirable as they can lead to catastrophic mechanical failures. Interference pins create interference fits with joined components to reduce stresses around fastener holes and extend the fatigue life of a structure. In this research, a novel method for finite element (FE) modeling of interference pin connections in a wind turbine lattice tower component was developed. The installation of interference pins was modeled using a two-stage process that causes local stiffness changes in joined members of the component. The local stiffness changes were accounted for in the FE model by using cylinders to represent the interference pins. An experimental setup, including a three-dimensional (3D) scanning laser Doppler vibrometer (SLDV) and a mirror, was used to measure out-of-plane and in-plane natural frequencies and mode shapes of the component. Ten out-of-plane modes and one in-plane mode from the FE model are compared with the experimental results to validate the accuracy of the FE modeling approach. The maximum percent difference between the theoretical and experimental natural frequencies of the component is 3.21%, and the modal assurance criterion (MAC) values between the theoretical and experimental mode shapes are 0.92 or greater, showing good agreement between the theoretical and experimental modal parameters of the component.

Limitations of Hydrogen Detection After 150 Years of Research on Hydrogen Embrittlement

Hydrogen's significance in contemporary society lies in its remarkable energy density, yet its integration into the worldwide energy grid presents a substantial challenge. Exposing materials to hydrogen environments leads to degradation of mechanical properties, damage, and failure. While the current approach for assessing hydrogen's impact on materials involves mainly multiscale modeling and mechanical testing, there exists a significant deficiency in detecting the intricate interactions between hydrogen and materials at the nanoatomic scales and under in situ conditions. This perspective review highlights the experimental endeavors aimed at bridging this gap, pointing toward the imminent need for new experimental techniques that can detect and map hydrogen in materials’ microstructures and their site‐specific dependencies.

Investigating the synergistic performance of masonry buildings with steel slabs in structural Design: A case of historical Mahmut Nedim Kurkcuoglu mansion in Turkey

The main aim of this study is to explore the collaborative performance of masonry structures incorporating steel slabs in their structural design. The focal point of the investigation is the historically significant Mahmut Nedim Kurkcuoglu Mansion located in Urfa, Turkey, renowned for its cultural heritage. The research methodology encompasses a comprehensive analysis of the mansion’s structural design, utilizing both numerical modeling and experimental testing. The findings of the study reveal that integrating steel beams into slabs within the structural design of masonry buildings can exert a significant influence on overall structural performance. This integration contributes to the heightened safety and durability of the structure. The results underscore the importance of accounting for the historical and cultural value of heritage buildings when implementing structural modifications. In terms of methodology, the research adds value to the field of structural engineering by offering insights into the incorporation of steel beams in the design of masonry structures. Moreover, it emphasizes the significance of preserving cultural heritage sites through sustainable and innovative engineering solutions. The study not only enriches the understanding of structural engineering but also holds practical implications for professionals such as architects, engineers, and preservationists engaged in the design and maintenance of heritage buildings. In conclusion, this research significantly contributes to the realms of both structural engineering and heritage preservation. Its implications extend to practical applications and can serve as a foundational platform for further exploration and investigation in this interdisciplinary domain.

Effective comparison of two potentially crossing hazard rate curves

In survival data analysis, comparison of two hazard rate curves is critically important for evaluating a treatment effect. In many applications, the two hazard curves could potentially cross each other, violating the proportional hazards assumption in the Cox's model. In such cases, the traditional tests like the log-rank test and the Peto-Peto test that were developed based on that assumption would be ineffective. There have been some discussions in the literature on comparison of two potentially crossing hazard curves, based on either parametric modeling or nonparametric testing approaches. However, the assumed models of the existing parametric methods are often difficult to justify in practice. On the other hand, the existing nonparametric tests are usually based on the maximization with respect to an unknown crossing point, leading to complex null distributions for the corresponding test statistics. We suggest a novel method in this paper for comparing two hazard curves based on a nonparametric testing procedure. Its test statistic avoids the maximization mentioned above and consequently has the desirable asymptotic normality property under some regularity conditions. We show that the new method is effective for comparing two potentially crossing hazard curves.

Research on the influencing factors of promoting flipped classroom teaching based on the integrated UTAUT model and learning engagement theory

With the rapid advancement of educational technology, the flipped classroom approach has garnered considerable attention owing to its potential for enhancing students’ learning capabilities. This research delves into the flipped classroom teaching methodology, employing the Unified Theory of Acceptance and Use of Technology (UTAUT), learning engagement theory, and the 4C skills (comprising communication, collaboration, creativity, and critical thinking) to investigate its effects on learning capabilities. The research surveyed 413 students from three universities in Jiangxi Province, employing stratified random sampling. SPSS 24.0 and Amos were used for structural equation modeling and hypothesis testing analysis. The findings indicate that: (1) Performance expectancy, effort expectancy, and peer influence significantly enhance students’ learning engagement in the flipped classroom. (2) Students’ learning engagement in the flipped classroom notably promotes their learning capabilities. (3) Performance expectancy, effort expectancy, and peer influence can significantly boost learning capabilities by increasing learning engagement. (4) Personality traits significantly moderate the effect of peer influence on learning engagement, highlighting the crucial role of individual differences in learning. (5) The level of students’ learning engagement is differentially influenced by performance expectancy and peer influence across various academic disciplines. Ultimately, this research provides valuable insights for educational policymakers and guides improvements in teaching practices, collectively advancing educational quality and equity.

Research on the Impact of Service Quality, Price, and Environment on Customer Loyalty towards Restaurants in Ho Chi Minh City

Research aimed to examine the impact of service quality, price, and restaurant environment on customer satisfaction and loyalty towards restaurants in Ho Chi Minh City. The author conducted a survey of 309 customers using a convenient sampling method and employed structural equation modeling (SEM) analysis and testing. The research results indicated that service quality, price, and restaurant environment all have an influence on customer satisfaction. Additionally, customer satisfaction was found to be a precursor to customer loyalty towards the restaurants. Based on these findings, the author proposed solutions to enhance customer satisfaction, thereby maintain and strengthen customer loyalty.

Calcium deposition in chicken eggshells: role of host genetics and gut microbiota

Eggshell is predominantly composed of calcium carbonate, making up about 95% of its composition. Eggshell quality is closely related to the amount of calcium deposition in the shell, which requires chickens to maintain a robust state of calcium metabolism. In this study, we introduced a novel parameter, Total Eggshell Weight (TESW), which measures the total weight of eggshells produced by chickens over a period of 10 consecutive d, providing valuable information on the intensity of calcium metabolism in chickens. Genome-wide association study (GWAS) was conducted to explore the genetic determinants of eggshell calcification in a population of 570 Rhode Island Red laying hens at 90 wk of age. This study revealed a significant association between a specific SNP (rs14249431) and TESW. Additionally, using random forest modeling and 2-tailed testing, we identified 3 genera, Lactobacillus in the jejunum, Lactobacillus, and Fournierella in the cecum, that exhibited a significant association with TESW. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis of claudin-1 and occludin genes in individuals with low TESW and high abundance of jejunal Lactobacillus confirmed that the inhibitory effect of jejunal Lactobacillus on calcium uptake was achieved through the up-regulation of tight junctions in intestinal epithelial cells. Notably, both host and microbial factors influence TESW, displaying a mutually influential relationship between them. The microbiome-wide Genome-Wide Association Study (mb-GWAS) identified significant associations between these 3 genera and specific genomic variants, such as rs316115020 and rs316420452 on chromosome 5, rs313198529 on chromosome 11, linked to Lactobacillus in the cecum. Moreover, rs312552529 on chromosome 1 exhibited potential association with Fournierella in the cecum. This study highlights the influence of host genetics and gut microbiota on calcium deposition in eggshells during the late laying phase, providing a foundational reference for studying calcium metabolism in hens.

Bivariate Lomax Distribution Based on Clayton Copula: Estimation and Prediction

Lomax distribution has been studied by many statisticians due to its important role in reliability modeling and lifetime testing. The bivariate Lomax distribution is an important lifetime distribution in survival analysis. In this article, a bivariate Lomax distribution is constructed based on Clayton copula. The joint probability density function and the joint cumulative distribution function are derived in closed forms. Some properties of this bivariate distribution are discussed. The maximum likelihood and Bayes estimators for the unknown parameters are derived. Also, the maximum likelihood and Bayesian two-sample prediction for the future observations are obtained. The performance of the proposed bivariate distribution is examined using a simulation study. Finally, one real data set under the proposed distribution is considered to illustrate its flexibility and applicability for real-life applications.

EMERGING PATHWAYS TO GREEN PURCHASE INTENTION: DECODING THE INFLUENCE OF ENVIRONMENTAL AWARENESS, GREEN PERCEIVED VALUE AND TECHNOLOGY ADOPTION MODEL ANTECEDENTS ON CONSUMERS’ PURCHASE INTENTION

Understanding the buying behaviour of consumers for green products has become an emerging issue. The purpose of present study is to assess purchase intention of consumers with respect to green products (environment friendly) shopping in India. Further, this study examines the role of environmental awareness, green perceived value, perceived usefulness and attitude towards using in building consumer intentions to purchase green products. Further, the study extends the TAM (Technology Adoption Model) by Davis (1989) by incorporating external variables like environmental awareness and green perceived value.This study examines the information gathered from 260 clients via a Google form survey. Structural equation modeling (SEM), validity and reliability testing, and exploratory factor analysis were conducted using the gathered data. The result of the present study shows that environmental awareness and green perceived value exert positive and differential effects on attitude towards using green products. The study also found that attitude and perceived usefulness are equally important for the purchase intention of customers towards green products. Implications of the present work are useful for academicians, marketers, customers, and policy makers.

Evaluation and application of kinetic models for Cu-catalyzed acetylene hydrochlorination

Evaluation and application of kinetic models for Cu-catalyzed acetylene hydrochlorination

Induced Pluripotent Stem Cells and CRISPR-Cas9 Innovations for Treating Alpha-1 Antitrypsin Deficiency and Glycogen Storage Diseases.

Human induced pluripotent stem cell (iPSC) and CRISPR-Cas9 gene-editing technologies have become powerful tools in disease modeling and treatment. By harnessing recent biotechnological advancements, this review aims to equip researchers and clinicians with a comprehensive and updated understanding of the evolving treatment landscape for metabolic and genetic disorders, highlighting how iPSCs provide a unique platform for detailed pathological modeling and pharmacological testing, driving forward precision medicine and drug discovery. Concurrently, CRISPR-Cas9 offers unprecedented precision in gene correction, presenting potential curative therapies that move beyond symptomatic treatment. Therefore, this review examines the transformative role of iPSC technology and CRISPR-Cas9 gene editing in addressing metabolic and genetic disorders such as alpha-1 antitrypsin deficiency (A1AD) and glycogen storage disease (GSD), which significantly impact liver and pulmonary health and pose substantial challenges in clinical management. In addition, this review discusses significant achievements alongside persistent challenges such as technical limitations, ethical concerns, and regulatory hurdles. Future directions, including innovations in gene-editing accuracy and therapeutic delivery systems, are emphasized for next-generation therapies that leverage the full potential of iPSC and CRISPR-Cas9 technologies.

Unlocking the Therapeutic Potential: Sitagliptin's Multifaceted Approach in Drug-Resistant Epilepsy through a Novel Mechanism Inhibiting Protein Kinase C-γ and a Long-Term Potentiation Pathway.

Drug-resistant epilepsy is a prominent challenge in chronic neurological disorders. Valproate, commonly used to treat epilepsy, can fail due to various side effects and interactions, necessitating the exploration of alternative treatments. Our study primarily investigated sitagliptin's potential as a therapeutic agent for drug-resistant epilepsy. Employing computational modeling and enzyme assay testing, three lead compounds, emixustat, sitagliptin, and distigmine bromide, were evaluated against the target enzyme protein kinase C-γ. In vivo, experiments on a pentylenetetrazolium-induced lamotrigine-resistant epilepsy model were conducted to test sitagliptin's antiseizure effects, compared with the standard phenobarbital treatment. Emixustat and sitagliptin showcased strong inhibitory properties, while distigmine bromide was less effective in the enzyme assay. Mechanistic insights revealed sitagliptin's ability to modulate the seizure grade and first myoclonic jerk latency via oxidative stress markers, like reduced glutathione and glutathione peroxidase emphasizing its antioxidative role in epilepsy. Additionally, it demonstrated anti-inflammatory effects by significantly reducing proinflammatory markers interleukin-1β and interleukin-6. The modulation of key genes of the long-term potentiation pathway, particularly protein kinase C-γ and metabotropic glutamate receptor 5, was evident through mRNA expression levels. Finally, sitagliptin showed potential neuroprotective properties, limiting pentylenetetrazolium-induced neuronal loss in the hippocampal region. Collectively, our findings suggest sitagliptin's multidimensional therapeutic potential for drug-resistant epilepsy specifically via a long-term potentiation pathway by inhibiting protein kinase C-γ.

Multifunctional Design of Triply Periodic Minimal Surface Structures for Temporary Pediatric Fixation Devices

Fracture fixation and limb deformity correction in pediatric orthopedics often use temporary metallic fixation devices. These devices’ higher stiffness compared to cortical bone leads to stress shielding, causing significant bone density reduction, periprosthetic loosening, and bone growth interference. The 3D‐printed triply periodic minimal surface (TPMS) structures present a promising engineering solution to match bone stiffness while ensuring reliable implant strength. In this study, finite‐element modeling and experimental testing are employed to identify optimal multifunctional TPMS‐based lattices that meet the required design constraints of 1) stiffness in the range of cortical bone, 2) strength in the range of cortical bone, 3) minimum osteointegration to facilitate the implant removal after healing, and 4) manufacturability with limited defect sensitivity. Six different types of TPMS structures in Ti–6Al–4V material manufactured via laser powder bed fusion are evaluated for their ability to target the lower and upper bounds of pediatric cortical bone stiffness. Lattices based on the Primitive unit cell design are superior, demonstrating the highest strength/stiffness ratio, best manufacturability, and potentially reduced osteointegration due to larger pore size, smaller surface area, and smallest negative Gaussian curvature compared to other investigated TPMS types.