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The production of modern composite materials based on bulk metallic glasses requires knowledge of their primary crystallization processes during heating (BMG). Here, we investigate the structure and crystallization kinetics of a promising modern BMG/B2 nano-composites, a fast-hardened glass-forming alloy Cu50Zr42.5Ti7.5. The complex four-step crystallization of the glass alloy at different heating rates was revealed by differential scanning calorimetry. The process of a crystallization was successfully fully described by a multiverse nonlinear kinetic model, and the kinetic parameters were determined with high accuracy. The best way to describe the four-step crystallization of a glass alloy is the two-branch parallel reaction. The first branch is described by three consecutive n-order autocatalytic reactions. The second branch obeys the Avrami-Erofeev model. The high thermal stability of the amorphous state is evidenced by the average full process crystallization activation energy Ea = 425 kJ mol−1. Analysis of the obtained results and their comparison with available literature data allow us to conclude that the crystallization process in glassy Cu50Zr42.5Ti7.5 alloy (and probably other similar ternary alloys based on binary Cu50Zr50 system) is strongly affected by the structure of initial sample as well as by thermal conditions. The presence of nano-sized inclusion of metastable phases (for example, B2 one) can change the sequence of reaction as well as the structure of phases forming at each stage. [ABSTRACT FROM AUTHOR]

Lampbrush chromosomes, with their unusually high rate of nascent RNA synthesis, provide a valuable model for studying mechanisms of global transcriptome up-regulation. Here, we obtained a whole-genomic profile of transcription along the entire length of all lampbrush chromosomes in the chicken karyotype. With nuclear RNA-seq, we obtained information about a wider set of transcripts, including long non-coding RNAs retained in the nucleus and stable intronic sequence RNAs. For a number of protein-coding genes, we visualized their nascent transcripts on the lateral loops of lampbrush chromosomes by RNA-FISH. The set of genes transcribed on the lampbrush chromosomes is required for basic cellular processes and is characterized by a broad expression pattern. We also present the first high-throughput transcriptome characterization of miRNAs and piRNAs in chicken oocytes at the lampbrush chromosome stage. Major targets of predicted piRNAs include CR1 and long terminal repeat (LTR) containing retrotransposable elements. Transcription of tandem repeat arrays was demonstrated by alignment against the whole telomere-to-telomere chromosome assemblies. We show that transcription of telomere-derived RNAs is initiated at adjacent LTR elements. We conclude that hypertranscription on the lateral loops of giant lampbrush chromosomes is required for synthesizing large amounts of transferred to the embryo maternal RNA for thousands of genes., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)