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Al/Mg bimetallic composites have drawn considerable attention for their promising lightweight applications in sectors such as the aerospace and automotive industries. In these systems, the interfacial behavior critically governs the overall performance and reliability. In this research, the molecular dynamics (MD) simulation was employed to systematically study the effects of pouring temperatures (923 K, 973 K, and 1023 K) and preheating temperatures (373 K, 473 K, and 573 K) on the interfacial diffusion behavior and fracture mechanism of the polycrystalline Al/Mg bimetallic system. The results indicate that the influencing rule of pouring temperatures and preheating temperatures on the interfacial diffusion behavior is consistent. Specifically, the diffusion coefficient of Mg atoms is higher than that of Al atoms, while the diffusion distance of Al atoms is significantly greater than that of Mg atoms. As the temperature increases, the thickness of the interfacial transition layer correspondingly rises. However, the effects of these two parameters on tensile fracture behavior demonstrate notable discrepancies. Specifically, the fracture mode evolves with pouring temperature, transitioning from being mediated solely by dislocations to being co-mediated by twins and dislocations. In contrast, the fracture mechanism remains solely dislocation-controlled, regardless of the preheating temperature. In addition, all the models fractured at the interface between the diffusion layer and the Mg matrix. The optimal tensile strength of 1.850 GPa was achieved at a pouring temperature of 923 K and a preheating temperature of 473 K, representing an improvement of approximately 52% compared to the lowest value recorded in the study. This research offers significant theoretical insights for the rational optimization of preparation parameters and an in-depth understanding of fracture mechanisms in Al/Mg bimetallic systems.

To ensure the prefabrication quality of concrete segmental beams for assembled railway bridges, this study investigates the main factors affecting the casting and curing of such beams. Using the Zheng-Xu regional railway bridge as a case study, this study analyzes the impact of environmental temperature, formwork materials, formwork thickness, pouring temperature, wind speed, and prestressed ducts on the thermal-structural coupled stresses in the beams, based on meteorological conditions at the prefabrication yard. A detailed concrete curing control plan is proposed. The research results show that formwork materials and pouring temperature have a significantly greater influence on the early thermal effects of prefabricated concrete segmental beams than other factors. Formwork materials exhibit the highest sensitivity to temperature and temperature stress, with sensitivities of 17.8% and 36.1%, respectively, followed by pouring temperature, which has sensitivities of 12.7% and 21.7% to temperature and temperature stress, respectively, and is positively correlated with peak temperature and peak stress. Wind speed and prestressed ducts are sensitive to temperature stress, with their sensitivities being less than 5%. Prestressed ducts promote internal heat dissipation in concrete segmental beams, reducing the internal peak temperature and the temperature difference between the interior and exterior, thereby lowering the risk of cracking. The better the thermal insulation performance of the formwork materials, the later and higher the temperature peak. Additionally, the thickness of the formwork materials has a greater impact on the temperature and stress of the segmental beam concrete. Based on the identified temperature field and thermal stress patterns for each significant factor, this study proposes detailed curing plans, including winter steam curing and summer spray curing. These strategies effectively reduce the internal-external temperature difference, minimize surface stresses, and mitigate the risk of cracking. The quality of prefabricated concrete segmental beams confirms the scientificity and rationality of the fine-curing control plan, which can serve as a reference for the detailed control of prefabrication and curing.

This study takes the commercial JG4246A cast Ni3Al-based superalloy as the research object, under the conditions of preheating the mold shell at 1020 °C and a pouring temperature of 1520 °C, characteristic simulation castings were poured. The microstructure and room temperature mechanical properties of different modulus sections of the castings were systematically investigated. It was found that, except for the edge towards the middle section of the larger modulus, the cooling rates at the edge were greater than those at the middle sections. The cooling rate was the fastest at the upper-right corner section (referring to the castings position during pouring, the same below), and the grain is the finest (approximately 0.46 mm), with the highest strength (tensile strength approximately 698 MPa, yield strength approximately 581 MPa), while the cooling rate at the lower-middle section was the slowest, and the grain was the largest (approximately 1.55 mm), with the lowest strength (tensile strength approximately 612.5 MPa, yield strength approximately t 524.5 MPa); the difference in grain size between the two is nearly 237%. The MC carbides at the lower-edge middle section have the smallest size (approximately 3.0 μm) and the elongation rate in this area is the highest (approximately 8.7%), while the MC carbides at the lower-middle section have the largest size (approximately 5.8 μm) and the elongation rate in this area is the lowest (approximately 4.9%); the size difference in the MC carbides between two is nearly 94%. This study clarifies the quantitative correlation between cooling rate, microstructure and properties, providing clear guidelines for optimizing the casting process of high-temperature alloys and subsequent studies on the uniformity of microstructure.

This study offers a novel method for recycling leftover concrete to create porous ceramic materials. Various pouring agents, such as starch mixed with flour, yeast, baking powder, wheat straw, or sawdust, have created porous waste concrete ceramic materials. The starch is a binder for ceramic particles and a growth substrate for forming gas bubbles. Utilizing starch consolidation procedures, the green bodies are produced by firing them at temperatures of 1200 °C, 1250 °C, and 1300 °C. Various techniques characterize the fired sample, including Fourier Transform Infrared Spectroscopy, Thermogravimetric analysis, Differential Scanning Calorimetry, Apparent porosity, Bulk density, Compressive strength, Phase composition, and Microstructure. The acquired results showed that apparent porosity decreased except for samples containing baking powders, while the bulk density and compressive strength increased as the firing temperature increased. With apparent porosity of 56% and 39%, bulk density of 1.27 g/cm3 and 1.64 g/cm3, and mechanical characteristics of 0.55 MPa and 1.47 MPa at 1250 °C and 1300 °C, respectively, samples containing flour have a highly porous structure. At 1250 °C, the thermal transmittance of this sample reaches 0.327 W/m2K. The sawdust-containing sample exhibited the highest strength, reaching 1.54 MPa at 1250 °C and 5.23 MPa at 1300 °C. At those respective temperatures, its apparent porosity measured approximately 55% and 38%. Additionally, sawdust samples had a thermal transmittance of up to 0.336 W/m2K. Therefore, the current study created porous structure ceramics by substituting all or some of the more expensive polymer additives with recycled concrete debris. The resulting ceramics are potentially used in gas burners, membranes, filters, and refractory thermal conductivity.

Plastics represent a major organic pollutant, but research focused on their biomonitoring in the air has only recently received attention. In the present work, we investigated the ability of Pittosporum tobira leaves to distinguish different levels of air contamination due to anthropogenic microfibers (MFs) in six urban sites characterized by different land uses (industrial, urban, and green), and the effect of wet/dry season on their accumulation. Moreover, the effect of pouring rain on MFs accumulation was estimated by transplants of P. tobira. Microfiber extraction was done by tape tearing on 1 g composite leaf samples on the leaf surface. In summer, the highest number of MFs were found in the leaves from the industrial site (160), followed by urban ones (84-125), and green parks (48-54). The accumulation of MFs was overall higher in summer than in winter, due to the rain-washing effect in the latter, and the different leaf traits observed in the two seasons. The development of glandular hairs during summer could contribute to increasing the accumulation of MFs observed in this period under conditions of reduced precipitation. In agreement, when comparing MFs fallout on leaves of sheltered and unsheltered transplants after a heavy rainfall, the number counted on the latter was significantly lower, suggesting that precipitations reduce MFs deposition. These findings reinforce the suitability of Pittosporum tobira leaves as a bioindicator for airborne anthropogenic MFs. Moreover, the pronounced seasonal differences, as well as the higher MFs loads during dry summer months, indicate that monitoring sensitivity is enhanced under low-rainfall conditions.

Bioplastics derived from renewable food crops or agricultural feedstocks are alternatives to petrochemical materials, but it is challenging to balance their mechanical properties, thermal stability, and shapeability. Here, we report a thermally stimulated supramolecular bioplastic that employs polyethylene glycol to optimize the assembly of cellulose and polyvinyl alcohol molecules. The resulting bioplastic showed a reinforced supramolecular architecture, with a mechanical elastic modulus of 3.23 GPa and an impact resistance higher than 8.15 kJ·m-1. It also showed thermal stability from -40 to 135 °C while maintaining its structural integrity and toughness, giving it potential applications for various shaping processes, including weaving, pouring, and molding. The bioplastic could also undergo natural soil biodegradation within 55 d and exhibited promising recyclability and economic feasibility. This study provides a strategy for configuring supramolecular structures and enhancing the design and manufacture of bioplastics with optimal comprehensive properties.

This study examined the geopolymerization behavior of granite waste powder and reactive silica powder (GWS), utilizing granite waste powder as a sustainable precursor material, to develop an environmentally friendly substitute for Ordinary Portland cement. To obtain this objective, a total of three different mixes of calcined granite waste with reactive silica (1:1, 3:2, 7:3) were cast to evaluate the aim of this study. Due to low inherent reactivity of granite waste powder, the alkali activation was achieved using a combined solution of alkali activators consisting of 8 mol/L concentration of NaOH and Na2SiO3 solution at mass ratio of 1:1.2 prepared 24 h in advance to ensure complete dissolution and stabilization prior to pouring it into the GWS paste. The finest particle size distribution for optimal reactivity performance was achieved by choosing lowest median particles size from 4.0 μm-4.2 μm among all mixtures. ICP-MS analysis of granite waste and reactive silica showed the presence of silica (0.11% and 0.26% respectively) and calcium (49.61% and 38.92% respectively) content adequate for effective geopolymerization of the paste. The elemental composition, new phase formation and microstructural analysis were examined using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) techniques and Scanning Electron Microscopy (SEM) analysis. XRD analysis revealed that all GWS mixes were predominantly amorphous, with crystalline quartz, feldspar and minor α-cristobalite peaks diminishing from GWS50 to GWS70 confirming increased reactivity due to enormous reactive silica content. FTIR spectra of GWS mixes displayed characteristics of O-H (3375 cm-1), H-O-H (1645 cm-1), and Si-O-T (982-1000 cm-1) bands, with the main Si-O-T peak shifting to higher wavenumbers from GWS50 to GWS70 due to increased GW content, indicating reduced geopolymerization effect in GWS50. SEM analysis revealed that among all mixes, GWS70 exhibited the most ideal dense matrix with increasing content of granite waste along with strong N-A-S-H gel formation. Compressive strength at 28 days increased from 11.2 MPa for GWS50 to 14.2 MPa for GWS60 and 13.8 MPa for GWS70, demonstrating that higher reactive silica powder content significantly enhanced the mechanical performance of the alkali-activated paste. These findings demonstrated that alkali-activated geopolymers of GSW offer a viable alternative to Ordinary Portland cement with optimized mixes by valorizing industrial waste and reducing reliance on high-carbon cement production.

The acceptance and effective use of assistive robotic arms by people with neurological conditions strongly depend on the usability of the control interface. This study evaluated the usability of a voice control system for an assistive robotic arm in both healthy participants and individuals with neurological disorders, and compared its applicability and effectiveness with conventional joystick control. A voice control module based on automatic speech recognition and text-to-speech feedback was developed for a commercially available 6-degree-of-freedom assistive robotic arm. The system was implemented using the Robot Operating System (ROS) and an Italian speech-recognition knowledge base. Voice control was tested in 20 healthy subjects and 20 individuals with varying levels of upper-limb impairment due to neurological diseases. Participants performed representative activities of daily living, including (i) pressing an elevator button, (ii) picking up a TV remote control, and (iii) pouring water into a glass. Task completion time, usability, and speech recognition accuracy were assessed and compared between voice and joystick control. All participants except one with neurological impairment were able to successfully use the voice interface, whereas only 11 could operate the joystick. Voice control achieved a recognition accuracy of 87% and a System Usability Scale (SUS) score corresponding to a “Good” adjective rating. Overall, these results indicate that voice control represents a promising and inclusive access modality, with the potential to improve the usability of assistive robotic arms, particularly for individuals with severe motor impairments.

Porosity formation due to solidification shrinkage and inadequate liquid metal feeding during the casting of Sn-0.3Ag-0.7Cu (SAC0307) is a critical issue that impairs quality and subsequent processing. However, the opacity of the casting process often obscures the quantitative relationships between process parameters and defect formation, creating a significant barrier to science-based optimization. To address this, the present study utilizes finite element method (FEM) analysis to systematically investigate the influence of pouring temperature (PCT, 290-390 °C) and interfacial heat transfer coefficient (HTC, 900-5000 W/(m2·K)) on this phenomenon. The results reveal that PCT exerts a non-monotonic effect on porosity by modulating the solidification mode, which governs the accumulation of dispersed microporosity. In contrast, HTC plays a critical role in determining porosity morphology by controlling both the solidification rate and mode. Consequently, an optimal processing window was identified at 350 °C PCT and 3000 W/(m2·K) HTC, which significantly enhances interdendritic feeding and improves the ingot's internal soundness. The efficacy of these optimized parameters was experimentally validated through macro- and microstructural characterization. This work not only elucidates the governing mechanisms of solidification quality but also demonstrates the value of numerical simulation for process optimization, offering a reliable scientific basis for the industrial production of high-quality SAC0307 alloys.

According to the embodied cognition framework, language is closely linked to the motor system and rehabilitation programs should stimulate language processing through the activation of motor and perceptual systems. In this study, we present an innovative training program based on the embodied cognition framework, using immersive technology to stimulate the perceptual-motor system through gesture observation from a first-person perspective. Post-stroke aphasic patients, in the post-acute phase and presenting with naming deficits, were assigned to one of two training conditions. The experimental group (EG) viewed videos of everyday gestures (i.e., pouring water, cutting carrots) from a first-person perspective, enhancing motor resonance, while the active control group (AC) viewed the same gestures from a third-person perspective. During video playback, the action was named by a female voice and the patient had to repeat it after video completion. The training was administered three times per week for four weeks. Naming abilities, along with other language and quality of life measures, were assessed pre- and post-intervention. Bayesian analysis of the primary outcome - percentage of rehabilitated items - yielded a Bayes factor BF+0 = 2.86, providing anecdotal-to-moderate evidence in favour of the first-person perspective group. The EG showed a higher mean percentage of rehabilitated items (M = 85.5%, SD = 22.5%) compared to the AC group (M = 50.5%, SD = 33.4%). No between-group differences were observed for broader language or quality-of-life measures. These preliminary, hypothesis-generating findings suggest greater efficacy of immersive, embodied gesture observation in promoting word retrieval recovery, and warrant replication in larger, adequately powered studies.

This article uses two examples of mixing to demonstrate why the constructal law and the second law are distinct, self-standing laws. It begins with the definitions of two distinct phenomena: irreversibility versus design in nature (form in motion, configuration, rhythm). These are summarized in two distinct statements, the second law and the constructal law. The first example of mixing concerns the movement of a body that sinks in a pool of liquid. The second example is about pouring ball bearings of two sizes into a box and shaking the box up and down. In both examples, the mixing process (the approach to no flow) is accompanied by the evolution of flow configuration. In the first example, evolving is the flow design around the sinking body. In the second example, evolving is the stratification of the balls. The juxtaposition of the constructal and second laws clarifies misunderstandings that tend to creep into thermodynamics regarding the physics of evolution, arrow of time, universe, and intangibles. The two examples came from the author's classroom; they teach the importance of free questioning and common sense (not jargon) on the way to discovering what flows, how it flows (with what design), and in what discernible direction (evolution).

This study evaluated the dimensional accuracy of alginate and elastomeric impression materials after spray and immersion disinfection and assessed the impact of storage duration on their stability. Impressions were made using alginate, condensation silicone, and addition silicone and disinfected using spray (Bacilol 25, Surfasept SA) and immersion (1% sodium hypochlorite and 2% glutaraldehyde). Impressions were stored for 1, 3, and 5 hours before pouring. Dimensional changes in stone casts were measured using a three-dimensional coordinate measuring machine (CMM) and analyzed using factorial ANOVA. Alginate impressions showed significant distortion with immersion disinfection, especially after 5 hours of storage (30.06 mm mean length). Spray disinfection provided better dimensional stability across all materials. Addition silicone exhibited minimal changes, making it more suitable for delayed pouring. Immersion disinfection caused greater distortion in alginate, while spray disinfection better preserved accuracy. Immediate pouring is recommended for alginate, while addition silicone remains stable for delayed use. Future research should assess spray disinfection's microbiological efficacy.

We are intimately familiar with liquids in our visual experience, yet the computational basis of liquid perception remains underexplored. This is an important knowledge gap because liquids, with their mutable shapes and complex intrinsic dynamics, differ remarkably from the commonly studied categories in computational vision, such as rigid objects or non-rigid solids. To understand the computational basis of liquid perception, we implemented different models of this ability and tested them in a new behavioral study. The models realize two distinct theoretical possibilities for the visual perception of liquid viscosity. The first possibility, and the focus of most existing work, explains the representation of liquid viscosity as a consequence of high-level image and motion statistics discriminative of the gradations of this physical property. A second, much different possibility is that the perceptual representations of liquids functionally map the physical processes of how viscosity and external forces (e.g., gravity, rigid surfaces) shape the way liquids move. We task these models and humans in a new behavioral task: making similarity judgments of liquid viscosity across pairs of animations depicting qualitatively different scenarios - e.g., a metal ball falling into a liquid container vs. liquid pouring over a non-flat surface. We find that a new model, Ripple, which builds and manipulates physics-based representations of liquid viscosity from sensory inputs, explains substantial variance in human judgments beyond powerful, previously behaviorally validated, statistical representations of viscosity. Moreover, statistical representations of viscosity across vastly different model architectures - a task-specific DNN and a general video foundation model - converge with one another, while remaining equally differentiated from Ripple. These results suggest that liquid perception extends beyond image statistics to also involve simulation-based intuitive physics.

Pouring water from a bottle into a glass requires representing their relative spatial positions (spatial information) and knowing that such objects are found together, or one by one (temporal dynamics), in typical contexts, such as a kitchen (semantic information).While spatial information is encoded using egocentric (body-centered) or allocentric (object-centered) reference frames, semantic knowledge is organized in context frames, which help predict object-context associations. This study investigates whether daily-like semantic contexts and temporal dynamics affect egocentric and allocentric spatial representations. Participants were immersed in semantically meaningless (abstract) or meaningful (bathroom, kitchen) virtual environments. They memorized triads of objects presented either simultaneously (static condition) or sequentially (dynamic condition) and then provided egocentric or allocentric spatial judgments. Results revealed an improvement of allocentric accuracy in meaningful rather than meaningless environments, whereas no differences emerged for egocentric spatial judgments. Crucially, this semantic benefit for allocentric encoding emerged only in the dynamic condition, where spatial information had to be integrated over time. These findings show that semantic context selectively facilitates allocentric spatial representations, particularly when perceptual input unfolds dynamically. The results support the interaction between semantic and spatial memory to shape how we perceive the surrounding world.

This prospective cohort study aimed to evaluate whether salivary leptin hormone levels correlate with skeletal and dental responses to functional therapy in normal-weight versus overweight skeletal class II malocclusion patients. Thirty-two patients with skeletal Class II division 1 malocclusion were divided into two groups: overweight and normal weight. All patients were treated with twin block appliances; their growth stage being about MP3cap. Lateral cephalometric x‑rays and body mass index (BMI) percentiles were assessed before (T0) and at the end of the functional treatment (T1). Unstimulated saliva samples were collected from all patients at four time points (before, in the first month, in the third month and at the end of the functional treatment) using a noninvasive passive pouring method. Leptin levels were measured photometrically using an enzyme-linked immunosorbent assay (ELISA) kit. Overweight patients exhibited higher salivary leptin levels and earlier skeletal maturation. Overjet correction was achieved in these patients with more incisor movement and they showed greater mandibular length increase. Correlation analysis revealed positive associations between leptin and the change of maxillary parameters as well as of soft tissue convexity. Negative correlations were observed between salivary leptin levels and changes in posterior facial height (PFH), PFH/AFH ratio (AFH: anterior facial height), and lower incisor inclination. Body weight significantly affected treatment timing and outcomes in Class II correction and should be considered in adolescent treatment planning. ZIELSETZUNG: Diese prospektive Kohortenstudie hatte zum Ziel zu untersuchen, ob der Leptinspiegel im Speichel mit den skelettalen und dentalen Ansprechen auf eine funktionelle Therapie bei normalgewichtigen Patienten im Vergleich zu übergewichtigen Patienten mit einer skelettalen Klasse-II-Malokklusion korreliert. Zweiunddreißig Patienten mit einer skelettalen Klasse-II/1-Malokklusion wurden in 2 Gruppen unterteilt: übergewichtige und normalgewichtige Patienten. Alle Patienten wurden mit Twin-Block-Apparaturen behandelt, dabei befand sich ihr Wachstumsstadium etwa bei MP3cap. Fernröntgenseitenaufnahmen und BMI(Body-Mass-Index)-Perzentilen wurden vor der funktionellen Behandlung (T0) und nach deren Abschluss (T1) ausgewertet. Von allen Patienten wurden an 4 Zeitpunkten (vor der Behandlung, im ersten Monat, im dritten Monat und nach Abschluss der funktionellen Behandlung) unstimulierte Speichelproben mittels einer nichtinvasiven passiven Gießmethode entnommen. Die Leptinspiegel wurden photometrisch mit einem ELISA(Enzyme-Linked Immunosorbent Assay)-Kit gemessen. Übergewichtige Patienten wiesen höhere Leptinspiegel im Speichel und eine frühere Skelettreifung auf. Bei diesen Patienten wurde die Overjet-Korrektur durch eine stärkere Bewegung der Schneidezähne erreicht, und sie zeigten eine stärkere Verlängerung des Unterkiefers. Die Korrelationsanalyse ergab positive Zusammenhänge zwischen Leptin und der Veränderung der Oberkieferparameter sowie der Weichgewebekonvexität. Negative Korrelationen wurden zwischen den Leptinspiegeln im Speichel und den Veränderungen der hinteren Gesichtshöhe (PFH), dem PFH/AFH-Verhältnis (AFH: vordere Gesichtshöhe) und der Neigung der unteren Schneidezähne beobachtet. Das Körpergewicht hatte signifikanten Einfluss auf den Behandlungszeitpunkt und die Ergebnisse bei der Klasse-II-Korrektur und sollte bei der Behandlungsplanung für Jugendliche berücksichtigt werden.

Introduction: Acrylic materials have been a staple in dental prosthetics for decades. Developments in manufacturing technology, including additive techniques, have led to the introduction of new types of acrylics, whose mechanical properties require detailed evaluation and comparison with conventional materials. Aim of the study: The aim of the study was to comparatively evaluate selected mechanical properties, such as hardness, impact strength, density, flexural strength, and tensile strength, of three types of acrylic materials used in prosthetics: 3D-printed acrylic, heat-cured acrylic, and cold-cured acrylic, in vitro. Materials and Methods: Three materials were used in the study: 3D-printed acrylic (NextDent Denture 3D+), heat-cured acrylic (made using the cupping method (Villacryl H Plus)), and cold-cured acrylic (made using the pouring method (Villacryl SP)). Ten samples (n = 30) were prepared from each material. Flexural strength, tensile strength, Young's modulus, density, Vickers hardness, and impact strength were tested. Results: The tested materials demonstrated significant differences in mechanical properties. The highest values for impact strength, flexural strength, tensile strength, and density were obtained for 3D-printed acrylic. Hot-cured acrylic achieved the highest hardness values. Cold-cured acrylic, on the other hand, achieved the lowest results, except for the impact strength test, where it achieved intermediate results. Conclusions: The mechanical properties of dental acrylics are significantly dependent on their manufacturing technology. Hot-cured acrylic exhibits the highest hardness, while 3D-printed acrylic is characterized by favorable impact strength, flexural strength, and tensile strength, which may have significant clinical significance in terms of the resistance of dentures to mechanical damage. The study results could provide a basis for introducing this material into clinical practice.

Bastos and Krupenye (2026, Science, 391: 583-586) present an innovative series of studies in which they explore the capacity of a single enculturated bonobo, Kanzi, to represent pretend objects-in other words-"imagination." Their experiments involved pantomimed actions of pouring and emptying juice or placing and dumping out grapes from transparent cups or bowls and asking Kanzi to indicate where the juice or grape would remain, indicating that he was tracking an imagined object, but they failed to account for cuing or alternative explanations. (PsycInfo Database Record (c) 2026 APA, all rights reserved).