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Synergistic approaches for hexapod mobility: comparative evaluation of structure, navigation, and control strategies on challenging terrains
Abstract The study delivers a cohesive system that combines structural stress investigation, navigational planning evaluation, and adaptive joint control to optimize hexapod effectiveness on hills, stairs, and uneven surfaces. The robot was developed through the iterative drafting technique and designed by assigning in PLA material. Structural examination with Finite Element Analysis (FEA) under 10 N and 20 N forces demonstrated a positive stress allocation and a safety factor of 2.8, combining compact development with durability. In the ROS/Gazebo exploration investigations utilizing global planners like A*, Dijkstra, RRT, and Artificial Potential Field (APF) in combination with a PID-driven local planner, A* as well as Dijkstra developed nearly the best pathways with 100% accuracy. This cut down on route variation by about 17% in comparison to RRT. RRT established confident that the exploration was always the same, but it established paths that were more lengthy and less smooth. APF, on the contrary, made paths that were smooth but less reliable due to the local minima. Adaptive synchronization for joint control quantitatively provided an improvement in joint angle stability, reducing oscillatory deviations by 12% and displacement errors by 15% relative to baseline controllers. The core novelty within this approach is the integrative methodology that will inherently synergize finite element structural analysis, comparative path planning, and Adaptive joint synchronization: presenting a comprehensive optimization strategy, new to hexapod robotics. Together, these advances allow for robust and efficient real-world deployment of hexapods. Future work will extend to hybrid learning-based planning, and sensor-driven dynamic adaptation.
A hierarchical framework to evaluate the usability of smartphone health applications
Biomechanical limits of hopping in the hindlimbs of giant extinct kangaroos
Abstract The locomotor abilities of animals depend upon their body size. Today, kangaroos are the largest hopping mammals, but some of their Pleistocene relatives were larger still—more than twice as heavy as any modern kangaroo. So, is there an upper size limit of bipedal hopping? Previous analyses have recovered an upper limit of ~ 140–160 kg based on allometry, but have suggested that incorporating changes in hindlimb scaling patterns among giant species would alter these conclusions. Here, we test this proposal by integrating scaling data from modern kangaroos with direct observation of the hindlimb bones of giant fossil kangaroos. We test two potential limiting factors on hopping—bone strength, and tendon size. We find that (a) the metatarsals of giant kangaroos would be capable of resisting the bending moments involved in hopping, and (b), the calcanea (heel bones) of giant kangaroos could accommodate tendons large enough to resist the loads generated during hopping. While hopping may not have been their primary mode of locomotion, our findings suggest that it may have formed part of a broader locomotor repertoire, for example for short bursts of speed.
Development of smart patient care robot with enhanced autonomous navigation through path optimization in hospital wards
Abstract This study presents the development of a smart patient-care robot designed to assist healthcare workers by automating routine monitoring tasks and enhancing autonomous mobility in hospital wards. Unlike conventional systems that rely on multiple sensors, the proposed platform achieves reliable navigation using a single two-dimensional light detection and ranging sensor combined with an enhanced D* lite algorithm. A key contribution of this work is the introduction of virtual obstacle spaces in occupancy grid maps, which simplify path planning and significantly increase the success rate of passing through narrow doorways, one of the most collision-prone scenarios in ward environments. Experimental results show a navigation success improvement of over 30%, confirming enhanced safety and efficiency in mobility. This research establishes a practical foundation for deploying patient-care robots in real hospital settings, showcasing both technical advances in autonomous navigation and the potential to reduce healthcare staff workload while ensuring patient safety.
Girls are starting puberty younger — why, and what are the risks?
The marginal male hypothesis explains only small amounts of spatial variation in density in pinnipeds
Long-read metagenomics reveals phage dynamics in the human gut microbiome
Factors associated with uptake of optimal dose of IPTP-SP among pregnant women attending antenatal clinics of Soroti district, Uganda
Rapid chemical characterization of finger millet using UHPLC-Q-Exactive orbitrap MS coupled with based via Feature-Based molecular networking and PRM
A joint range–angle–velocity estimation algorithm for FDA-MIMO radar based on graph signal processing
Specificity, length and luck drive gene rankings in association studies
Abstract Standard genome-wide association studies (GWAS) and rare variant burden tests are essential tools for identifying trait-relevant genes 1 . Although these methods are conceptually similar, by analysing association studies of 209 quantitative traits in the UK Biobank 2–4 , we show that they systematically prioritize different genes. This raises the question of how genes should ideally be prioritized. We propose two prioritization criteria: (1) trait importance — how much a gene quantitatively affects a trait; and (2) trait specificity — the importance of a gene for the trait under study relative to its importance across all traits. We find that GWAS prioritize genes near trait-specific variants, whereas burden tests prioritize trait-specific genes. Because non-coding variants can be context specific, GWAS can prioritize highly pleiotropic genes, whereas burden tests generally cannot. Both study designs are also affected by distinct trait-irrelevant factors, complicating their interpretation. Our results illustrate that burden tests and GWAS reveal different aspects of trait biology and suggest ways to improve their interpretation and usage.
Shape information used for face identity and expression recognition is highly versatile and context specific
Optimization and accuracy analysis of track straightness measurement based on total station free station method
Abstract Aiming at the problems that the traditional method of total station in high-precision track straightness measurement is greatly restricted by the on-site environment, and the error control is difficult, this study proposes the free station method of the total station to establish a nonlinear measurement point deviation calculation model. Based on the Monte Carlo simulation, the influences of different angular measurement errors, distance measurement errors, and total station erection positions on the accuracy of the free station method are systematically analyzed. To ensure the accuracy of the deviation of measurement points, high-precision angular measurement is the key. Optimizing the total station erection position can eliminate distance measurement errors. The total station is set up at 50 m and 100 m along the 160-meter track, respectively, with a vertical distance of 4 m from the track. The mean square error of deviation of most measurement points along the entire line is successfully controlled within ± 0.3 mm. This method can be widely applied in engineering fields such as high-speed railways, precision guide rails, and large-scale structural installations, where sub-millimeter-level position tolerance detection is required in complex environments.
Machine learning for predicting functional outcomes in acute ischemic stroke: insights from a nationwide stroke registry
Discovery of Goethe’s amber ant: its phylogenetic and evolutionary implications
Abstract Museum collections remain essential scientific resources, especially when revisited using modern analytical techniques. In an interdisciplinary study, we examined the overlooked amber collection of Johann Wolfgang von Goethe (1749–1832), polymath and pioneer of art and natural science. Using synchrotron-based micro-computed tomography (SR-µ-CT), we identified a fossil ant from Baltic amber (Eocene ~ 47–34 Ma) in Goethe’s collections. The specimen is assigned to † Ctenobethylus goepperti (Mayr in Die Ameisen des Baltischen Bernsteins. Beiträge zur Naturkunde Preussens, 1868), which we redescribe and re-diagnose, proposing † Eldermyrmex exsectus Dubovikoff et Dlussky, 2019 as its junior synonym (syn. nov., comb. nov.). We further infer a potential sister-group relationship with the extant genus Liometopum Mayr, 1861, suggesting that † C. goepperti may have been a dominant arboreal species in warm-temperate coniferous forests, a scenario which is supported by its abundance in Baltic amber. Critically, our results document endoskeletal structures in a Cenozoic fossil ant, underscoring both the morphological value of historical collections and the lasting scientific legacy of Goethe’s naturalist vision.
A comparative evaluation of parafoveal and perifoveal macular vessel density loss in glaucoma using 3 × 3 mm OCTA scans
Abstract In a prior study we demonstrated the strong performance of convolutional neural networks (CNNs) in distinguishing healthy from glaucomatous eyes and subsequent analysis suggested that CNNs rely on the vessel density (VD) of the perifoveal area for making their predictions. Those findings are of particular interest because current 3 × 3 mm macular optical coherence tomography angiography (OCTA) analysis mostly focuses on the parafoveal area, excluding the perifoveal region. The aim of this study is to further investigate this observation and evaluate whether perifoveal VD offers greater diagnostic accuracy in differentiating healthy from glaucomatous eyes than parafoveal VD. For conducting this study, 3 × 3 mm macular OCTA scans where acquired by the Spectralis OCT II device of 352 eyes, consisting of 198 glaucomatous and 154 healthy eyes. The different layers of the retina were automatically segmented by the manufacturer’s software and sectioned into the superficial vascular plexus (SVP), intermediate capillary plexus (ICP) and deep capillary plexus (DCP). Support vector machines (SVMs) were then trained on perifoveal and parafoveal VD for each plexus, whereby parafoveal VD was computed on 12 sectors within a 1.45 mm radius centered at the fovea, while parafoveal VD was trained on 4 quadrants covering the remaining area of the scan. 10-fold cross-validation was used to select the SVMs with the highest mean area under the receiver operating characteristic curve (AUROC) and evaluated on a held-out test set. Differences in AUROC between methods were pairwise statistically tested with Bonferroni correction. It was found that perifoveal VD outperformed parafoveal VD across all plexuses, with the highest improvement observed in the SVP (AUROC perifoveal 0.943 vs. parafoveal 0.897, p = 0.025), followed by the ICP (AUROC perifoveal 0.872 vs. parafoveal 0.851) and DCP (AUROC perifoveal 0.795 vs. parafoveal 0.786). Our results demonstrate that perifoveal VD in 3 × 3 mm macular OCTA scans offers a higher diagnostic performance in distinguishing healthy from glaucomatous eyes than parafoveal VD. These findings suggest that incorporating the perifoveal region into macular OCTA analysis could yield additional information on glaucoma, especially when focusing on the SVP. Furthermore, our findings propose to reconsider the value of 3 × 3 mm macular scans in VD analysis, whose utility appears to be underestimated.
Fifty years of seismicity of Mt. Vesuvius
Probing quantum mechanics with nanoparticle matter-wave interferometry
Abstract The quantum superposition principle is a fundamental concept of physics 1 and the basis of numerous quantum technologies 2,3 . Yet, it is still often regarded counterintuitive because we do not observe its key features on the macroscopic scales of our daily lives. It is, therefore, interesting to ask how quantum properties persist or change as we increase the size and complexity of objects 4 . A model test for this question can be realized by matter-wave interferometry, in which the motion of individual massive particles becomes delocalized and needs to be described by a wave function that spans regions far larger than the particle itself 5 . Over the years, this has been explored with a series of objects of increasing mass and complexity 6–9 and a growing community aims at pushing this to ever larger limits. Here we present an experimental platform that extends matter-wave interference to large metal clusters, a qualitatively new material class for quantum experiments. We specifically demonstrate quantum interference of sodium nanoparticles, which can each contain more than 7,000 atoms at masses greater than 170,000 Da. They propagate in a Schrödinger cat state with a macroscopicity 10 of μ = 15.5, surpassing previous experiments 5,9,11 by an order of magnitude.
Effect of physical activity intervention on insulin resistance and appendicular body composition in gestational diabetes mellitus
Abstract The prevalence of gestational diabetes mellitus (GDM) is increasing worldwide, and a further increase is expected in the coming years. One of the common risk factors for GDM is reduced physical activity (PA), leading to impaired glycemic control and increased insulin resistance (IR). Hence, the objective of the study was to determine the effects of PA intervention on IR and appendicular body composition in individuals with GDM. After screening 135 participants, 52 were included based on the selection criteria. The eight-week PA intervention and an educational booklet with information about GDM and PA intervention were administered to the participants. A detailed analysis of the outcome measures was conducted at baseline and postintervention, including Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and appendicular body composition via body impedance analysis. There was a significant decrease in the HOMA-IR value (MD = 0.123, p < 0.05) and upper extremity (MD = 0.4, p < 0.05), and lower extremity (MD = 0.12, p < 0.05) fat mass‒muscle mass index. The eight-week PA intervention effectively improved insulin resistance and the appendicular body composition among pregnant women with GDM.