8 results match your criteria: "Kryvyi Rih State Pedagogical University[Affiliation]"

Article Synopsis
  • Researchers propose a new method for creating multiple shape memory polymers (SMPs) by mixing immiscible polymers under high pressure and shear, rather than traditional blending techniques.
  • This approach allows for nanoscale homogeneity (40-95 nm) in the blends, improving both shape memory and mechanical performance.
  • The study focused on a blend of polypropylene (PP) and polystyrene (PS), demonstrating that the processed blend achieves a strong triple shape memory effect with high shape fixation and recoverability, along with adjustable transition temperatures.
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This paper presents the novel development of a shape memory polymer foam based on polymer-polymer nanocomposites. Herein, polylactide (PLA)/biosourced polyamide (PA) foams are fabricated by in situ fibrillation of polymer blends and a subsequent supercritical CO foaming technique. In this system, PLA serves as a shape memory polymer to endow this foam with a shape memory effect (SME), and in situ generated PA nanofibers are employed to reinforce the PLA cell walls and provide an additional permanent phase.

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In situ-generated nanofibrillar polymer-polymer composites are excellent candidates for the production of polymer materials, with high mechanical and SME properties. Their special feature is the high degree of dispersion of the in situ-generated nanofibers and the ability to form entangled nanofiber structures with high aspect ratios through an end-to-end coalescence process, which makes it possible to effectively reinforce the polymer matrix and, in many cases, increase its ductility. The substantial interfacial area, created by the in situ formed fiber/matrix morphology, significantly strengthens the interfacial interactions, which are crucial for shape fixation and shape recovery.

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Using histological cross-sections, the chondrocranium anatomy was reconstructed for two developmental stages of Hermann's tortoise (Testudo hermanni). The morphology differs from the chondrocrania of most other turtles by a process above the ectochoanal cartilage with Pelodiscus sinensis being the only other known species with such a structure. The anterior and posterior processes of the tectum synoticum are better developed than in most other turtles and an ascending process of the palatoquadrate is missing, which is otherwise only the case in pleurodiran turtles.

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Background: In February 2022 the Russian federation started a new invasion of Ukraine as an escalation of the ongoing war since 2014. After nine years of war and the COVID-19 pandemic, the mental health state of Ukrainians requires systematic monitoring and relevant action. The aim of present study was to investigate the state of mental health among Ukrainians assessing the levels of stress, anxiety, and post-traumatic stress disorder (PTSD) prevalence in not displaced persons (NDPs), internally displaced persons (IDPs), and refugees abroad.

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The full-scale escalation of Russia's war against Ukraine in 2022 created a surge of mental health issues, requiring urgent, evidence-based interventions to reduce trauma and mitigate stress. Reflecting recommendations from leading specialists in the field, Ukrainian mental health professionals sought to develop appropriate skills and knowledge for working in wartime through advanced training programs. This study aimed to investigate the experiences of Ukrainian mental health professionals having completed advanced training in mental health topics in wartime.

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This study addresses the mechanical behavior of lattice materials based on flexible thermoplastic polyurethane (TPU) with honeycomb and gyroid architecture fabricated by 3D printing. Tensile, compression, and three-point bending tests were chosen as mechanical testing methods. The honeycomb architecture was found to provide higher values of rigidity (by 30%), strength (by 25%), plasticity (by 18%), and energy absorption (by 42%) of the flexible TPU lattice compared to the gyroid architecture.

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Recent years have seen considerable progress in applying single nucleotide polymorphisms (SNPs) to population genetics studies. However, relatively few have attempted to use them to study the genetic differentiation of wild bird populations and none have examined possible differences of exonic and intronic SNPs in these studies. Here, using 144 SNPs, we examined population genetic differentiation in the saker falcon (Falco cherrug) across Eurasia.

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