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REBa 2 Cu 3 O 7−δ (REBCO, RE = rare earth elements) cryomagnets have considerable potential for magnetic applications due to their high field trapping capacities over 10 T at temperatures below 77 K. The controlled nucleation of REBCO crystals for attaining superior performance decisively relies on the seeding strategy related to seed material and seeding assembly. Recently, buffer-assisted seeding approaches have been developed for reliable growth, in which buffer-crystals are by-products and discarded after splitting off from main crystals as ceramic waste though containing certain expensive matters such as RE, Ag and Pt. Here, for the first time, we succeeded in utilizing YBCO and NdBCO/Ag buffer-crystals as seeds for producing REBCO crystals under maximum processing temperatures of 1015 ℃ and 1053 ℃, respectively. YBCO specimens were characterized by differential scanning calorimetry and secondary ion mass spectrometry. It was verified that the buffer-crystal was 5.5 K higher than the normal-crystal in peritectic temperature (T p). Furthermore, the highly distributed Mg element was identified in the upper middle part of buffer-crystal, which was diffused from the Mg-involved NdBCO seed in previous fabrication. It is the Mg existence that enhanced T p of the buffer-crystal and made it highly thermal stable in seeding YBCO growth. In contrast to expensive commercial film-seeds and multistep home-prepared crystal-seeds, buffer-crystal-seeds distinctively have cost- and time-saving benefits. Most importantly, the current success adds new value of reusability to buffer-assisted seeding approaches towards a sustainable fabrication of REBCO cryomagnets. [ABSTRACT FROM AUTHOR]

High cognitive reserve (CR) protects against cognitive decline in individuals with white matter hyperintensities (WMH). However, the functional mechanisms remain relatively unknown. This work aimed to explore the effects of CR on the frontoparietal control network (FPCN) and cognitive function in subjects with WMH. One hundred and thirty-seven subjects with WMH and 95 control subjects without WMH underwent neuropsychological testing, CR assessments, and multimodal magnetic resonance imaging (MRI) scanning. A mixed analysis of covariance with CR level (high CR vs. low CR) and WMH status (with WMH vs. without WMH) as fixed factors was performed on the FPCN. WMH volume was negatively correlated with global cognitive function in subjects with low CR not in those with high CR, suggesting a buffering effect of high CR. An interaction between CR and WMH was detected on the right FPCN in frontal regions. Specifically, control subjects with high CR had significantly higher functional connectivity (FC) in frontal regions than control subjects with low CR, whereas this relation was inverted in WMH subjects. Correlative analyses showed positive associations of the FC with cognitive performance in both WMH subjects and control subjects, although the associations were not significant after correction for multiple comparisons. In conclusion, CR differentially regulated the FPCN in frontal regions between subjects with WMH and those without WMH. This regulation supports the flexibility of CR in regulating brain function and may underlie the effects of CR on cognitive function in WMH subjects. • CR buffers the damaging effect of WMH on cognitive function. • CR interacts with WMH to regulate the frontoparietal control network (FPCN). • CR differentially regulates the FPCN between WMH subjects and control subjects. [ABSTRACT FROM AUTHOR]

Highlights: [•] Large sized Ag-free SmBCO bulk with high performance was prepared in air. [•] An YBCO buffered NdBCO thin film on MgO substrate was used to guarantee a proper maximum processing temperature (T max). [•] We introduced Ba-rich Sm2Ba4Cu2O y (Sm242) phase into this work to ensure a high T c (over 94K). [•] Sm2Ba4CuBiO z (Sm2411) phase was employed to further reinforce J c (about 68KA/cm2). [Copyright &y& Elsevier]