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Relationship between CO2 Emissions and Energy Consumption Sub-types Under Impact of AI-Related Patents and Energy-Related R&D Investments: Evidence from the USA by Novel Quantile-Based Methods
No full textElectrospun poly(ε-caprolactone) transdermal patches incorporating donepezil HCl and natural additives: fabrication, characterization, and drug release studies
No full textAbstractPoly(ε-caprolactone) (PCL) is a biodegradable polyester that stands out among biopolymersdue to its unique advantages, making it a subject of extensive research.Its hydrophobic nature, slow degradation rate, and synthetic origin make PCL particularlysuitable for various drug delivery systems. The present study aims to investigatethe potential of transdermal electrospun nanofibers based on PCL loadedwith Donepezil HCl (DNP-HCl). These fibers, fabricated using the electrospinningtechnique, utilize a drug solution to control the release of DNP-HCl, a medicationcommonly used to treat Alzheimer’s disease. In addition, natural componentssuch as the antibacterial agent boric acid, okra seed powder (OCP) known for itsantioxidant properties, and penetration-enhancing agents have been successfullyincorporated into the nanofiber structure in order to prevent the proliferation ofundesired bacteria. Morphological and structural characterization of the DNP-HClloaded nanofibers were performed by scanning electron microscopy (SEM) andFourier-transform infrared spectroscopy (FTIR). The controlled release of DNPHClat pH 7.4 reached 96.2% cumulative release at 24 h for the PCL/DNP (5:2)nanofibrous transdermal patch successfully incorporated with OCP and boric acid.The release profiles of DNP-HCl from the prepared drug delivery system exhibitedsustained behavior, which was best described by the Korsmeyer-Peppas kineticmodel. The stability tests conducted in five different environments have shown thatthe presence of natural additives in the nanofiber structure effectively ensures theirdurability. These results suggest that nanofiber transdermal patches based on PCLhold promise for drug delivery due to their high stability.</p
Social Media Addiction and Mental Well-Being: Social Connectedness and Perceived Social Support as Serial Mediators
No full textWhile social media connects individuals with one another, the quality of these connections raises concerns from a mental health perspective. Examining the relationship between social media addiction (SMA) and mental well-being (MWB), as well as the key variables associated with this relationship is pertinent to mental health. This cross-sectional study addresses the serial mediating roles of social connectedness and perceived social support in the relationship between SMA and MWB. The study sample consisted of 451 adults residing in Turkey, from various occupational backgrounds, aged between 18 and 60 years (%65.19 female, Mage = 30.85 years, SD = 8.72). The data collected within the scope of the study were analyzed using a two-step structural equation modeling (SEM) approach. To determine the indirect effects, a bootstrapping analysis was conducted. The results indicated that social connectedness and perceived social support serially mediated the relationship between SMA and MWB. In the current study, it was found that high levels of SMA were associated with lower levels of MWB, contributing to the understanding of key variables related to MWB. These findings indicate that social connectedness and perceived social support are important indicators of MWB, and that considering these variables in prevention and intervention programs may be beneficial
Early detection of thermal runaway in lithium-ion batteries under extreme conditions using phase change materials
No full textIn the current study, a machine learning model for the early detection of thermal runaway in lithium-ion batteries is developed. A nickel manganese cobalt battery is modeled and validated using a multi-scale multi-domain approach. Following model validation, the cell is coated with phase change material and thermal runaway is triggered by an external heat source. In the simulation phase, 144 thermal runaway data are obtained. The voltage, current, phase change material temperature, and battery temperature data are recorded in time-series. After the preparation of the data set, a long short-term memory model is built to predict the thermal runaway at an early stage. Once the prediction model is built, the trade-off relationship between the prediction performance of the model and the training time is investigated in more detail. As a result, it was found that the thermal runaway onset time could be predicted with an error of 5.33 seconds using the first 40 seconds of battery operation data in training and after 70 seconds of model evaluation. Increasing the training time to 120 seconds decreased the thermal runaway onset time prediction error to 2.67 seconds
System identification and model reference adaptive control of bipedal locomotion with neural networks
No full textIrreversible adsorption behavior of CuS nanoplate-based QCM sensors toward aqueous Ammonia: Adsorption kinetics and isotherm insights
No full textIn this study, the ammonia (NH₃/NH₄+) sensing performance of two-dimensional covellite phase copper sulfide (CuS) nanoplates in aqueous media was investigated for the first time using QCM-based sensors. Hydrothermally synthesized CuS nanoplates were characterized by X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FE-SEM) analyses. The CuS-coated quartz crystal microbalance (QCM) electrode exhibited clear and concentration-dependent frequency shifts ranging from approximately 1.4 to 2 MHz for NH₃ concentrations between 18.25 and 91.25 ppm. It was observed that the frequency shifts were related to NH₃ adsorption, and at higher concentrations, irreversible adsorption became dominant on the surface. UV–vis measurements showed these findings, and chemical changes in the solution pointed to the adsorption mechanism. The BET analysis also confirmed the mesoporous nature of the CuS nanoplates, providing a suitable surface for NH₃ adsorption and correlating well with the concentration-dependent QCM frequency shifts. The Elovich model showed the best fit in kinetic analyses, and the Langmuir model in isotherm analyses. These results demonstrate that both monolayer and heterogeneous adsorption behaviors are effective on the CuS surface. The findings provide a basis for the development of next-generation, low-cost, and portable CuS-based sensors that can be used in areas such as environmental monitoring, water quality control, and nuclear waste management
Comparative study of 3D-Printable polymers for beta interaction behaviours via monte carlo simulations
No full textThe rapid advancement of 3D printing technologies has revolutionised production in many sectors due to the versatile properties of printable materials. Thermal, mechanical and functional performance of 3D printable components make them suitable for use in radiation-intensive environments such as betavoltaic cells and clinical phantoms. This study investigates the behaviour of 3D-printable materials, including ABS, PLA, PETG, TPU, and UV resins, under exposure to various beta radiation sources, such as 3H, 63Ni, 14C, 147Pm, 99Tc, 90Sr, and 90Y, through a comparative analysis of their beta radiation attenuation efficiency, energy absorption, and dose transmission characteristics. TPU exhibited a surface flux reduction of approximately 72.3 % for tritium (3H) and 69.8 % for nickel-63 (63Ni) at a thickness of 0.1 µm, demonstrating better attenuation performance for low-energy beta radiation. A new metric, Half Absorption Thickness (HAT), was introduced to quantify the shielding capacity more precisely; the lowest HAT was found for TPU under 3H (0.08 mm), and the highest for PETG under 99Tc (1.12 mm). The derived logarithmic models (R2 > 0.99) enable estimation of shielding efficiency as a function of material thickness and beta energy. Among all tested combinations, ABS exhibited the best attenuation performance against high-energy beta particles, with a maximum flux reduction of 87.1 % for 90Sr and a corresponding HAT of 0.48 mm, establishing it as the most efficient barrier material in the studied energy range. Conversely, UV-cured resin demonstrated the highest beta transmission, particularly under 3H and 63Ni exposure, making it a suitable candidate for applications where controlled dose delivery is desired. These findings contribute to the literature by offering a comparative evaluation of the attenuation performance of 3D printable materials against different beta radiation sources and by providing a basis for material selection in beta applications
Exploring the potential of nanotechnology for early detection of cancer disease by microfluidic paper based analytical devices
No full textCancer is the second most common cause of mortality over the last few years in the worldwide. Late diagnosis of this disease is the main cause of death among cancer patients. Conventional methods do not have enough sensitivity for timely diagnosis. So sensitive, fast and available diagnostic devices are highly needed for diagnosis in the early stages. Due to the change in the size and shape of cancer cells compared to normal cells, biosensors are a suitable option for cancer diagnosis. In recent years, to miniaturization of the biosensors in order to use them better, easier and to reduce costs, researchers introduced microfluidic biosensors. Microfluidic paper-based biosensors (μPBs), used as point-of-care (POC) diagnostic devices, could eliminate the need for expensive and time-consuming procedures in conventional cancer diagnosis. In this review, we will evaluate the efficacy of nanotechnology in paper-based microfluidic biosensors for early stage cancer diagnosis
İnsan Faktörünün İş Kazaları Üzerindeki Etkilerinin ve Kaza Önleyici Sistemlerin İncelenmesi: Sistematik Bir İnceleme
No full textİş sağlığı ve güvenliği (İSG) çalışanların sağlığının ve güvenliğinin korunmasını, üretim güvenliğinin sağlanmasını, güvenli ve sağlıklı bir çalışma ortamının sürdürülmesini amaç edinen multidisipliner bir alandır. Çalışma ortamında, çalışanları ve işyerlerini doğrudan etkileyecek İSG tehlikeleriyle karşı karşıya kalınmaktadır. İSG tehlikelerinin önlenmesine yönelik tedbirler uygulamaya koyulamaz ise iş kazaları kaçınılmaz olmaktadır. İş kazalarına yol açan makine, ortam, insan ve yönetim gibi nedenler olmakla birlikte işyerlerinde gerçekleşen iş kazalarının önemli bir kısmı insan kaynaklı olarak gerçekleşmektedir. İnsan kaynaklı iş kazalarına yönelik proaktif yaklaşımla önleyici faktörlerin geliştirilmesi iş kazalarının azaltılması noktasında önemli bir katkı sunacaktır. Bu bağlamda çalışmada iş kazaları ile insan faktörü arasındaki ilişkinin ve insan faktörü etkenli iş kazalarının önlenmesine yönelik sistemlerin incelenmesi amaçlanmıştır. Amaca yönelik olarak gerçekleştirilen sistematik taramada, Web of Science, Scopus ve Science Direct veri tabanlarında 2010-2024 yılları arasındaki literatür taranmıştır. Belirlenen anahtar kelimelere ve dahil etme kurallarına göre ulaşılan literatür, PRISMA modeli ile analiz edilmiş ve nihai olarak 61 çalışmaya ulaşılmıştır. Çalışmalar, insan faktörü ve iş kazası ilişkisini ele alış biçimlerine göre incelenmiştir. Çalışmaların %46’sı, insan faktörünün iş kazalarının gerçekleşmesinde bir etkisinin olup olmadığını ortaya çıkarmaya yönelik olarak yürütülmüştür. Bu çalışmaların genel bir sonucu olarak, insan faktörünün iş kazalarını arttırdığı yargısına ulaşılmaktadır. Çalışmaların %33’ünde, insan faktöründen kaynaklı iş kazalarını önlemek amacıyla risk analizi gerçekleştirilmiştir. Risk analizi, iş kazalarının minimize edilmesi için proaktif bir önlem olarak uygulanmıştır. Çalışmaların %21’i ise, insan faktöründen kaynaklı iş kazalarını önlemeye yönelik sistemlerin geliştirildiği çalışmalardan oluşmaktadır. İş kazası tahmin yöntemlerinin ve işyerlerinde sürekli izleme sistemlerinin geliştirildiği çalışmalara daha az rastlanmakla birlikte veri odaklı risk analizlerine ve yapay zeka destekli sistemlere verilecek önem ile iş kazalarının önlenmesi yönünde kritik bir adım atılacağı düşünülmektedir.</p