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34 pages, 27180 KiB  
Article
Lifetime Variations in Prolactin Expression in the Hippocampus and Dentate Gyrus of the Rat
by Marta Carretero-Hernández, Elisa Herráez, Leonardo Catalano-Iniesta, David Hernández-González, David Díez-Castro, Ana E. Rodríguez-Vicente, Josefa García-Barrado, Teresa Vicente-García, Miguel Robles-García, Enrique J. Blanco and José Carretero
Int. J. Mol. Sci. 2025, 26(15), 7299; https://doi.org/10.3390/ijms26157299 - 28 Jul 2025
Abstract
Prolactin is a hormone with demonstrated roles in the brain, including neurogenesis, neuroprotection, learning, stress response or memory consolidation. To determine the prolactin expression in the rat hippocampus during aging and to resolve some controversies related to the presence of prolactin in the [...] Read more.
Prolactin is a hormone with demonstrated roles in the brain, including neurogenesis, neuroprotection, learning, stress response or memory consolidation. To determine the prolactin expression in the rat hippocampus during aging and to resolve some controversies related to the presence of prolactin in the hippocampus, the aim of this study was to analyze whether changes occur in the expression of prolactin during different stages of life. To determine this, we designed an experimental study in which we analyzed the expression and location of prolactin in the rat hippocampus, Ammon’s horn and Dentate Gyrus, during different stages of life (prepubertal, postpubertal, young adult, adult and old) and checked if there are differences related to sex. Overall, the results obtained show that prolactin is present in the rat hippocampus and that prolactin is synthesized, as deduced from the findings obtained via ELISA, immunohistochemistry, qPCR and in situ hybridization. After analyzing the correlation between serum and hippocampal prolactin levels and comparing the amounts of Prl mRNA and the hormone, the results obtained suggest that hippocampal prolactin has a dual origin: local synthesis of the hormone and its passage from the blood. On the other hand, the amounts of prolactin and its mRNA in the hippocampus vary with sex and age, suggesting the existence of age-related sexual dimorphism. The results obtained suggest that hippocampal aging is related to a decrease in the hippocampal prolactin system, which helps to better understand brain aging. Full article
(This article belongs to the Special Issue Understanding Aging in Health and Disease)
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13 pages, 1130 KiB  
Article
Feasibility and Preliminary Results of a Standardized Stair Climbing Test to Evaluate Cardiorespiratory Fitness in Children and Adolescents in a Non-Clinical Setting: The “Hand Aufs Herz” Study
by Federico Morassutti Vitale, Jennifer Wieprecht, Maren Baethmann, Delphina Gomes, Anja Tengler, Roxana Riley, Samar Shamas, Marcel Müller, Guido Mandilaras, Simone Katrin Manai, Maria Jaros, Nikolaus Alexander Haas and Meike Schrader
Children 2025, 12(8), 993; https://doi.org/10.3390/children12080993 - 28 Jul 2025
Abstract
Background/Objectives: Cardiorespiratory fitness (CRF) is of great interest in children and adolescents. Due to the limited availability of cardiopulmonary exercise testing, simple and reliable alternatives are needed. A stair climbing test (SCT) for the assessment of CRF developed at the Department of [...] Read more.
Background/Objectives: Cardiorespiratory fitness (CRF) is of great interest in children and adolescents. Due to the limited availability of cardiopulmonary exercise testing, simple and reliable alternatives are needed. A stair climbing test (SCT) for the assessment of CRF developed at the Department of Pediatric Cardiology of the LMU University Hospital in Munich showed a strong correlation with VO2max. The aim of this study is to prove its feasibility in a non-clinical setting and to analyse its results in a larger study population. Methods: During the “Hand aufs Herz” study, a comprehensive cardiovascular examination was carried out on 922 pupils and siblings (13.2 ± 7.8 years) at a high school in Bavaria. The SCT was performed to evaluate CRF: participants had to run up and down a total of four floors (14.8 m) as quickly as possible without skipping steps or holding on to the banister. Absolute time has been normalized over the standard height of 12 m to allow comparisons with different settings. An SCT Index was calculated to adjust results to the different weights of participants and the exact height of the staircase. Results: The SCT proved to be easily feasible and safe in non-clinical contexts. Out of 922 participants, 13 (1.4%) were not able to perform the test, and 3 (0.3%) had to interrupt it following fatigue or stumbling. A total of 827 participants aged from 9 to 17 years (13.1 ± 2.1 years, 45.8% girls) had a mean absolute SCT time of 53.4 ± 6.2 s and 43.3 ± 5.1 s when normalized over 12 m. Conclusions: The SCT represents a simple, cost- and time-saving test that allows a rapid and solid assessment of cardiorespiratory fitness in children and adolescents. We could demonstrate that it is safe and feasible in non-clinical contexts. Its short duration and universal applicability are valuable advantages that could facilitate the establishment of a repetitive cardiovascular screening in the pediatric population, particularly in outpatient departments or settings with low-resource systems. Full article
(This article belongs to the Special Issue Prevention of Cardiovascular Diseases in Children and Adolescents)
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20 pages, 826 KiB  
Systematic Review
Patient-Reported Outcomes in Intraoral Bone Block Augmentation Compared to GBR Procedures Prior to Implant Placement: A Systematic Review
by Sepehr Salahi, M. Kamal Shaar, Jeremy Pitman, Stijn Vervaeke, Jan Cosyn, Faris Younes and Thomas De Bruyckere
J. Clin. Med. 2025, 14(15), 5331; https://doi.org/10.3390/jcm14155331 - 28 Jul 2025
Abstract
Objective: To compare the effect of different bone augmentation procedures, namely, autogenous bone blocks (ABBs) versus guided bone regeneration (GBR), on patient-reported outcomes (PROMs). Methods: This systematic review was conducted according to the PRISMA guidelines. A MEDLINE, Embase, and Web of [...] Read more.
Objective: To compare the effect of different bone augmentation procedures, namely, autogenous bone blocks (ABBs) versus guided bone regeneration (GBR), on patient-reported outcomes (PROMs). Methods: This systematic review was conducted according to the PRISMA guidelines. A MEDLINE, Embase, and Web of Science search was conducted by two independent reviewers in combination with a free-hand search in relevant journals until June 2025. Outcomes were PROMs to enhance our understanding of the evolution of these procedures. Results: The electronic search yielded 6291 articles. After title screening, 67 articles were further analyzed for abstract review, which resulted in 14 articles eligible for full-text reading. Six articles were finally included based on the exclusion and inclusion criteria with a total of 295 patients. The overall study quality was low, since only two RCTs could be included. One study demonstrated a high risk of bias. Different PROMs were examined and compared such as pain, edema, neurosensory disturbance, Patient-Reported Predominant Symptom, OHIP-14, postoperative analgesic usage, willingness to repeat, and likelihood to recommend. Meta-analysis was not achievable due to a lack of direct comparisons and heterogeneity in terms of PROMs. Evaluation points varied between pretreatment and up to nearly 10-years of follow-up. Conclusions: Despite significant heterogeneity and reporting, this systematic review concluded that ABB and GBR are well-tolerated procedures. Trends such as transient postoperative pain and swelling with a minor occurring of neurosensory disturbances were reported in a few studies. Overall, a good perception of postoperative recovery was reported for both treatment modalities. Good quality of life was noted related to GBR procedures. Patient-reported outcomes were only analyzed for patients who completed the entire follow-up period. This may introduce bias, as patients who dropped out and were more likely to experience complications were not represented, potentially resulting in a more favorable portrayal of the outcomes. Further well-conducted prospective studies with a long follow-up are needed for an evidence-based evaluation and comparison of PROMs for these procedures. Full article
(This article belongs to the Section Dentistry, Oral Surgery and Oral Medicine)
17 pages, 1601 KiB  
Perspective
A Perspective on Quality Evaluation for AI-Generated Videos
by Zhichao Zhang, Wei Sun and Guangtao Zhai
Sensors 2025, 25(15), 4668; https://doi.org/10.3390/s25154668 - 28 Jul 2025
Abstract
Recent breakthroughs in AI-generated content (AIGC) have transformed video creation, empowering systems to translate text, images, or audio into visually compelling stories. Yet reliable evaluation of these machine-crafted videos remains elusive because quality is governed not only by spatial fidelity within individual frames [...] Read more.
Recent breakthroughs in AI-generated content (AIGC) have transformed video creation, empowering systems to translate text, images, or audio into visually compelling stories. Yet reliable evaluation of these machine-crafted videos remains elusive because quality is governed not only by spatial fidelity within individual frames but also by temporal coherence across frames and precise semantic alignment with the intended message. The foundational role of sensor technologies is critical, as they determine the physical plausibility of AIGC outputs. In this perspective, we argue that multimodal large language models (MLLMs) are poised to become the cornerstone of next-generation video quality assessment (VQA). By jointly encoding cues from multiple modalities such as vision, language, sound, and even depth, the MLLM can leverage its powerful language understanding capabilities to assess the quality of scene composition, motion dynamics, and narrative consistency, overcoming the fragmentation of hand-engineered metrics and the poor generalization ability of CNN-based methods. Furthermore, we provide a comprehensive analysis of current methodologies for assessing AIGC video quality, including the evolution of generation models, dataset design, quality dimensions, and evaluation frameworks. We argue that advances in sensor fusion enable MLLMs to combine low-level physical constraints with high-level semantic interpretations, further enhancing the accuracy of visual quality assessment. Full article
(This article belongs to the Special Issue Perspectives in Intelligent Sensors and Sensing Systems)
31 pages, 19389 KiB  
Article
Enhancing Prediction by Incorporating Entropy Loss in Volatility Forecasting
by Renaldas Urniezius, Rytis Petrauskas, Vygandas Vaitkus, Javid Karimov, Kestutis Brazauskas, Jolanta Repsyte, Egle Kacerauskiene, Torsten Harms, Jovita Dargiene and Darius Ezerskis
Entropy 2025, 27(8), 806; https://doi.org/10.3390/e27080806 - 28 Jul 2025
Abstract
In this paper, we propose examining Heterogeneous Autoregressive (HAR) models using five different estimation techniques and four different estimation horizons to decide which performs better in terms of forecasting accuracy. Several different estimators are used to determine the coefficients of three selected HAR-type [...] Read more.
In this paper, we propose examining Heterogeneous Autoregressive (HAR) models using five different estimation techniques and four different estimation horizons to decide which performs better in terms of forecasting accuracy. Several different estimators are used to determine the coefficients of three selected HAR-type models. Furthermore, model lags, calculated using 5 min intraday data from the Standard & Poor’s 500 (SPX) index and the Chicago Board Options Exchange Volatility (VIX) index as the sole exogenous variable, enrich the models. For comparison and evaluation of the experimental results, we use three metrics: Quasi-Likelihood (QLIKE), Mean Absolute Error (MAE), and Mean Squared Error (MSE). An empirical study reveals that the Entropy Loss Function consistently achieves the best QLIKE results in all the horizons, especially in the weekly horizon. On the other hand, the performance of the Robust Linear Model implies that it can provide an alternative to the Entropy Loss Function when considering the results of the MAE and MSE metrics. Moreover, research shows that adding more informative lags, such as Realized Quarticity for the Heterogeneous Autoregressive model yielding the Realized Quarticity (HARQ) model, and incorporating the VIX index further improve the general results of the models. The results of the proposed Entropy Loss Function and Robust Linear Model suggest that they successfully achieve significant forecasting accuracy for HAR models across multiple forecasting horizons. Full article
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14 pages, 1150 KiB  
Article
Psychology or Physiology? Choosing the Right Color for Interior Spaces to Support Occupants’ Healthy Circadian Rhythm at Night
by Mansoureh Sadat Jalali, Ronald B. Gibbons and James R. Jones
Buildings 2025, 15(15), 2665; https://doi.org/10.3390/buildings15152665 - 28 Jul 2025
Abstract
The human circadian rhythm is connected to the body’s endogenous clock and can influence people’s natural sleeping habits as well as a variety of other biological functions. According to research, various electric light sources in interior locations can disrupt the human circadian rhythm. [...] Read more.
The human circadian rhythm is connected to the body’s endogenous clock and can influence people’s natural sleeping habits as well as a variety of other biological functions. According to research, various electric light sources in interior locations can disrupt the human circadian rhythm. Many psychological studies, on the other hand, reveal that different colors can have varied connections with and a variety of effects on people’s emotions. In this study, the effects of light source attributes and interior space paint color on human circadian rhythm were studied using 24 distinct computer simulations. Simulations were performed using the ALFA plugin for Rhinoceros 6 on an unfurnished bedroom 3D model at night. Results suggest that cooler hues, such as blue, appear to have an unfavorable effect on human circadian rhythm at night, especially when utilized in spaces that are used in the evening, which contradicts what psychologists and interior designers advocate in terms of the soothing mood and nature of the color. Furthermore, the effects of Correlated Color Temperature (CCT) and the intensity of a light source might be significant in minimizing melanopic lux to prevent melatonin suppression at night. These insights are significant for interior designers, architects, and lighting professionals aiming to create healthier living environments by carefully selecting lighting and color schemes that support circadian health. Incorporating these considerations into design practices can help mitigate adverse effects on sleep and overall well-being, ultimately contributing to improved occupant comfort and health. Full article
(This article belongs to the Section Building Energy, Physics, Environment, and Systems)
20 pages, 2901 KiB  
Article
Exploring the Use of Eye Tracking to Evaluate Usability Affordances: A Case Study on Assistive Device Design
by Vicente Bayarri-Porcar, Alba Roda-Sales, Joaquín L. Sancho-Bru and Margarita Vergara
Appl. Sci. 2025, 15(15), 8376; https://doi.org/10.3390/app15158376 - 28 Jul 2025
Abstract
This study explores the application of Eye-Tracking technology for the ergonomic evaluation of assistive device usability. Sixty-four participants evaluated six jar-opening devices in a two-phase study. First, the participants’ gaze was recorded while they viewed six rendered pictures of assistive devices, each shown [...] Read more.
This study explores the application of Eye-Tracking technology for the ergonomic evaluation of assistive device usability. Sixty-four participants evaluated six jar-opening devices in a two-phase study. First, the participants’ gaze was recorded while they viewed six rendered pictures of assistive devices, each shown in two different versions: with and without rubber in the grip area. Second, the participants physically interacted with the devices in a hands-on usability task. In both phases, participants rated the devices according to six usability affordances: robustness, comfort, easiness to grip, lid slippery, effort level, and easiness to use. Eye-Tracking metrics (fixation duration, number of fixations, and visit duration) correlated with the on-screen ratings, which aligned with ratings after using the physical devices. High ratings in comfort and effort level correlated with more visual attention to the grip area, where the rubber acted as key signifier. Heatmaps revealed the grip area as important for comfort and easiness to use and the lid area for robustness and slipperiness. These findings demonstrate the potential of Eye Tracking in usability studies, providing valuable insights for the ergonomic evaluation of assistive devices. Moreover, they highlight the suitability of Eye Tracking for early-stage design evaluation, offering objective metrics to guide design decisions and improve user experience. Full article
(This article belongs to the Special Issue Advances in Human–Machine Interaction)
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24 pages, 268 KiB  
Article
On the Continuity of Wittgenstein’s “Religious Point of View”
by Haiqiang Dai
Religions 2025, 16(8), 979; https://doi.org/10.3390/rel16080979 - 28 Jul 2025
Abstract
It is widely acknowledged that there is a similarity between Wittgenstein’s later conception of language and a “religious point of view.” An equally well-received view is that there is an essential shift in Wittgenstein’s thought from early to later. However, what both of [...] Read more.
It is widely acknowledged that there is a similarity between Wittgenstein’s later conception of language and a “religious point of view.” An equally well-received view is that there is an essential shift in Wittgenstein’s thought from early to later. However, what both of these contentions ignore is that there is also a similarity between his early philosophy and the “religious point of view”, the negligence of which has led to an exaggeration of the divergence between his early and later philosophy. This paper aims to show that Wittgenstein in fact conducted his early philosophical work from a “religious point of view” and continued to demonstrate such a view in his later writings. I will first identify some essential characteristics of the “religious point of view” in Wittgenstein’s early philosophy by focusing on the mystical. I will then illustrate how these characteristics continue and are developed further in his later thought. The findings of this paper are critical in two ways: on the one hand, they clarify a host of misunderstandings through a comparative investigation into Wittgenstein’s early and later thought; on the other, they provide a more comprehensive overview of Wittgenstein’s “religious point of view,” which will help to deepen our understanding of his philosophy. Full article
(This article belongs to the Special Issue New Work on Wittgenstein's Philosophy of Religion)
16 pages, 2592 KiB  
Article
Finger Patterns as a Tool for Teaching and Learning About Number Relations Exceeding 10 in the Many Hands Activity
by Anna-Lena Ekdahl and Angelika Kullberg
Educ. Sci. 2025, 15(8), 968; https://doi.org/10.3390/educsci15080968 - 28 Jul 2025
Abstract
In this study, we investigate the learning opportunities offered in the enactment of a finger pattern activity with numbers exceeding 10 that shows how smaller units can be composed into larger units. Research on early arithmetic learning shows the importance of students understanding [...] Read more.
In this study, we investigate the learning opportunities offered in the enactment of a finger pattern activity with numbers exceeding 10 that shows how smaller units can be composed into larger units. Research on early arithmetic learning shows the importance of students understanding numbers as composed units and making use of arithmetic strategies that are based on unitizing rather than single-unit counting. The Many Hands activity was enacted in an intervention program focusing on 6-year-olds’ learning of structuring numbers and number relations during one school year, conducted in collaboration with teachers. The activity, with numbers exceeding 10, was enacted at the end of the program. Video observations of 19 teaching episodes in which the activity was used were analyzed using the variation theory of learning. The analysis focused on identifying which aspects of numbers were made visible for students to discern and how finger patterns became a tool for structuring numbers and number relations. Five aspects were made visible in the enactments of the Many Hands activity: (i) small numbers as composed units; (ii) units within units; (iii) units within units and new, larger units; (iv) relationships between units in the number system; and (v) place value. In 12 of the 19 episodes, the teacher or the students used their fingers to show and see the structure of numbers in relation to the identified aspects. Full article
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20 pages, 642 KiB  
Article
Impact of Audio Delay and Quality in Network Music Performance
by Konstantinos Tsioutas, George Xylomenos and Ioannis Doumanis
Future Internet 2025, 17(8), 337; https://doi.org/10.3390/fi17080337 - 28 Jul 2025
Abstract
Network Music Performance (NMP) refers to network-based remote collaboration when applied to music performances, such as musical education, music production and live music concerts. In NMP, the most important parameter for the Quality of Experience (QoE) of the participants is low end-to-end audio [...] Read more.
Network Music Performance (NMP) refers to network-based remote collaboration when applied to music performances, such as musical education, music production and live music concerts. In NMP, the most important parameter for the Quality of Experience (QoE) of the participants is low end-to-end audio delay. Increasing delays prevent musicians’ synchronization and lead to a suboptimal musical experience. Visual contact between the participants is also crucial for their experience but highly demanding in terms of bandwidth. Since audio compression induces additional coding and decoding delays on the signal path, most NMP systems rely on audio quality reduction when bandwidth is limited to avoid violating the stringent delay limitations of NMP. To assess the delay and quality tolerance limits for NMP and see if they can be satisfied by emerging 5G networks, we asked eleven pairs of musicians to perform musical pieces of their choice in a carefully controlled laboratory environment, which allowed us to set different end-to-end delays or audio sampling rates. To assess the QoE of these NMP sessions, each musician responded to a set of questions after each performance. The analysis of the musicians’ responses revealed that actual musicians in delay-controlled NMP scenarios can synchronize at delays of up to 40 ms, compared to the 25–30 ms reported in rhythmic hand-clapping experiments. Our analysis also shows that audio quality can be considerably reduced by sub-sampling, so as to save bandwidth without significant QoE loss. Finally, we find that musicians rely more on audio and less on video to synchronize during an NMP session. These results indicate that NMP can become feasible in advanced 5G networks. Full article
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24 pages, 56885 KiB  
Article
Bio-Crafting Architecture: Experiences of Growing Mycelium in Minimal Surface Molds
by Anca-Simona Horvath, Alina Elena Voinea and Radu Adrian Arieșan
Sustainability 2025, 17(15), 6835; https://doi.org/10.3390/su17156835 - 28 Jul 2025
Abstract
Mycelium is a living material that has gained popularity over the last decade in both architecture and design. Apart from understanding the physical behaviour of novel materials, it is also important to grasp how designers and the general audience perceive them. On the [...] Read more.
Mycelium is a living material that has gained popularity over the last decade in both architecture and design. Apart from understanding the physical behaviour of novel materials, it is also important to grasp how designers and the general audience perceive them. On the one hand, this study investigated mycelium growth in 3D-printed minimal surface shapes using a wood-based filament, and on the other hand, it examined how both designers and the general public experience interacting with mycelium. Using a material-driven design research method, a workshop with architecture students was conducted where various triply periodic minimal surfaces were designed and 3D printed. These shapes were used as molds and impregnated with mycelium, and the growth of mycelium was analyzed visually and photographically. Data on the experiences of the 30 workshop participants of working with mycelium was collected through a survey and analyzed qualitatively. After exhibiting results of the workshop in a public-facing exhibition, semi-structured interviews with members of the general public about their perceptions of mycelium were conducted. Three-dimensionally printed minimal surfaces with wood-based filaments can function as structural cores for mycelium-based composites, and the density of the minimal surface appears to influence mycelium growth, which binds to wood-based filaments. Students exhibited stronger feelings for living materials compared to non-living ones, displaying both biophilia and, to a lesser extent, biophobia. Introducing hands-on workshops with living and experimental materials in design studio settings can help future generations of designers develop sensibilities for, and a critical approach towards, the impact of their design decisions on the environment and sustainability. The study also contributes empirical data on how members of the general public perceive mycelium as a material for design. Full article
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21 pages, 11260 KiB  
Article
GaN HEMT Oscillators with Buffers
by Sheng-Lyang Jang, Ching-Yen Huang, Tzu Chin Yang and Chien-Tang Lu
Micromachines 2025, 16(8), 869; https://doi.org/10.3390/mi16080869 - 28 Jul 2025
Abstract
With their superior switching speed, GaN high-electron-mobility transistors (HEMTs) enable high power density, reduce energy losses, and increase power efficiency in a wide range of applications, such as power electronics, due to their high breakdown voltage. GaN-HEMT devices are subject to long-term reliability [...] Read more.
With their superior switching speed, GaN high-electron-mobility transistors (HEMTs) enable high power density, reduce energy losses, and increase power efficiency in a wide range of applications, such as power electronics, due to their high breakdown voltage. GaN-HEMT devices are subject to long-term reliability due to the self-heating effect and lattice mismatch between the SiC substrate and the GaN. Depletion-mode GaN HEMTs are utilized for radio frequency applications, and this work investigates three wide-bandgap (WBG) GaN HEMT fixed-frequency oscillators with output buffers. The first GaN-on-SiC HEMT oscillator consists of an HEMT amplifier with an LC feedback network. With the supply voltage of 0.8 V, the single-ended GaN oscillator can generate a signal at 8.85 GHz, and it also supplies output power of 2.4 dBm with a buffer supply of 3.0 V. At 1 MHz frequency offset from the carrier, the phase noise is −124.8 dBc/Hz, and the figure of merit (FOM) of the oscillator is −199.8 dBc/Hz. After the previous study, the hot-carrier stressed RF performance of the GaN oscillator is studied, and the oscillator was subject to a drain supply of 8 V for a stressing step time equal to 30 min and measured at the supply voltage of 0.8 V after the step operation for performance benchmark. Stress study indicates the power oscillator with buffer is a good structure for a reliable structure by operating the oscillator core at low supply and the buffer at high supply. The second balanced oscillator can generate a differential signal. The feedback filter consists of a left-handed transmission-line LC network by cascading three unit cells. At a 1 MHz frequency offset from the carrier of 3.818 GHz, the phase noise is −131.73 dBc/Hz, and the FOM of the 2nd oscillator is −188.4 dBc/Hz. High supply voltage operation shows phase noise degradation. The third GaN cross-coupled VCO uses 8-shaped inductors. The VCO uses a pair of drain inductors to improve the Q-factor of the LC tank, and it uses 8-shaped inductors for magnetic coupling noise suppression. At the VCO-core supply of 1.3 V and high buffer supply, the FOM at 6.397 GHz is −190.09 dBc/Hz. This work enhances the design techniques for reliable GaN HEMT oscillators and knowledge to design high-performance circuits. Full article
(This article belongs to the Special Issue Research Trends of RF Power Devices)
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15 pages, 447 KiB  
Article
Effects of a 12-Week Exercise Intervention on Primitive Reflex Retention and Social Development in Children with ASD and ADHD
by Norikazu Hirose, Yuki Tashiro and Tomoya Takasaki
Children 2025, 12(8), 987; https://doi.org/10.3390/children12080987 - 28 Jul 2025
Abstract
Objective: Retained primitive reflexes are associated with delayed motor and behavioral development in children with autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD). This study examined the effects of a 12-week structured exercise intervention on reflex integration, motor coordination, and socio-behavioral outcomes in [...] Read more.
Objective: Retained primitive reflexes are associated with delayed motor and behavioral development in children with autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD). This study examined the effects of a 12-week structured exercise intervention on reflex integration, motor coordination, and socio-behavioral outcomes in these populations. Method: Fifteen children with ASD (13 boys, 2 girls) and twelve with ADHD (8 boys, 4 girls), aged 6–12 years, participated in rhythmic, balance, and coordination-based exercises. Primitive reflexes, including the asymmetrical tonic neck reflex (ATNR), were assessed using standardized protocols, and fine motor coordination was evaluated using the Finger and Thumb Opposition Test (FOT). Behavioral outcomes were measured using the Social Responsiveness Scale-2 (SRS-2) for the ASD group and the Conners 3 for the ADHD group. Results: The ASD group showed significant reductions in left-standing ATNR retention scores (p = 0.012) and improvements in right-hand FOT scores (p = 0.023). In the ADHD group, significant improvements were also observed in right-hand FOT scores (p = 0.007). Furthermore, Conners 3 Total and Global Index scores significantly decreased in the ADHD group (p = 0.016 and 0.020, respectively). Reflex retention patterns appeared broader and more bilateral in ASD than in ADHD, suggesting distinct motor developmental profiles. Conclusions: Short-term rhythmic, balance, and whole-body coordination exercise interventions may support behavioral and motor development in children with ASD and ADHD. Tailored programs emphasizing reflex integration hold promise for clinical and educational applications. Full article
(This article belongs to the Special Issue Effects of Exercise Interventions on Children)
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18 pages, 1372 KiB  
Article
Enhanced Calibration Method for Robotic Flexible 3D Scanning System
by Zhilong Zhou, Jinyong Shangguan, Xuemei Sun, Yunlong Liu, Xu Zhang, Dengbo Zhang and Haoran Liu
Sensors 2025, 25(15), 4661; https://doi.org/10.3390/s25154661 - 27 Jul 2025
Abstract
Large-sized components with numerous small key local features are essential in advanced manufacturing. Achieving high-precision quality control necessitates accurate and highly efficient three-dimensional (3D) measurement techniques. A flexible measurement system integrating a fringe-projection-based 3D scanner with an industrial robot is developed to enable [...] Read more.
Large-sized components with numerous small key local features are essential in advanced manufacturing. Achieving high-precision quality control necessitates accurate and highly efficient three-dimensional (3D) measurement techniques. A flexible measurement system integrating a fringe-projection-based 3D scanner with an industrial robot is developed to enable the rapid measurement of large object surfaces. To enhance overall measurement accuracy, we propose an enhanced calibration method utilizing a multidimensional ball-based calibrator to simultaneously calibrate for hand-eye transformation and robot kinematic parameters. Firstly, a preliminary hand-eye calibration method is introduced to compensate for measurement errors at observation points, leveraging geometric-constraint-based optimization and a virtual single point derived via the barycentric calculation method. Subsequently, a distance-constrained calibration method is proposed to jointly estimate the hand-eye transformation and robot kinematic parameters, wherein a distance error model is constructed to link parameter errors with the measured deviations of a virtual single point. Finally, calibration and validation experiments were carried out, and the results indicate that the maximum and average measurement errors were reduced from 1.053 mm and 0.814 mm to 0.421 mm and 0.373 mm, respectively, thereby confirming the effectiveness of the proposed method. Full article
(This article belongs to the Special Issue Applications of Manufacturing and Measurement Sensors: 2nd Edition)
16 pages, 1419 KiB  
Article
Dynamic Parameters Identification of Serial Robot Based on Dual Quaternion
by Guozhi Li, Dongjie Li, Xinyue Yin, Wenping Chen and Haibo Feng
Appl. Sci. 2025, 15(15), 8362; https://doi.org/10.3390/app15158362 - 27 Jul 2025
Abstract
This paper studies the dynamic parameters identification problem of load and linkages of a serial robot in the presence of model uncertainty. The dynamic parameters of load and linkages of a serial robot have been identified through a combination procedure, which is useful [...] Read more.
This paper studies the dynamic parameters identification problem of load and linkages of a serial robot in the presence of model uncertainty. The dynamic parameters of load and linkages of a serial robot have been identified through a combination procedure, which is useful for different platforms of serial robot systems. The purpose of this paper is to propose a dynamic parameter identification method for a serial robot based on a dual quaternion. Using the information of the force and torque of the load obtained by the six-dimensional force sensor installed on the end-effector of the robot, the dynamics parameter identification matrix of the load is derived, which also uses the information of motion speed and acceleration of the end-effector. On the other hand, the analysis of the dynamic relationship between adjacent linkages and the joints is based on dual quaternion algebra, and the identification matrix for the dynamic parameters and the difference values of associated linkages are derived, as well. The combination procedure of the method is flexible in the application of dynamic parameters identification for a serial robot using a dual quaternion. Furthermore, the proposed DQ (dual quaternion)-based method in this paper has the advantage of lower cost compared with the RBFNN (radial basis function neural network)-based method. The effectiveness of the proposed dynamic parameter identification method for a serial robot has been verified by relevant experiments. Full article
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