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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]

To precisely prevent stroke, we evaluated three platelet function tests and their associations with clinical outcomes in ischemic stroke patients. On-treatment platelet reactivity of acute minor stroke patients taking aspirin plus clopidogrel was tested by light transmittance aggregometry (LTA), thromboelastography (TEG) and platelet function analyzer (PFA). Mann-Whitney U tests and receiver operating characteristic (ROC) curve analysis were used to assess their associations with recurrent events and clinical outcome prediction. 127 acute minor stroke patients were stringently selected and followed for 13 months. Eight patients (6.3%) self-reported the recurrence and 13 (10.2%) patients self-reported bleeding. Recurrent patients displayed significantly higher on-treatment platelet reactivity when measured with LTA (p = 0.030) and PFA (p < 0.001). Further ROC analysis demonstrated that LTA and PFA had modest-to-fair ability to predict stroke recurrence (LTA: area under the curve [AUC], 0.765; 95% CI, 0.584–0.945, PFA: AUC, 0.832; 95% CI, 0.658–1.000). However, TEG (measured by the platelet inhibition rate) could not detect the difference between recurrent patients and non-recurrent patients (p = 0.515) and predict recurrent events (AUC, 0.569; 95% CI, 0.368–0.770). None of the tests were associated with bleeding except for PFA (p < 0.001), with AUC of PFA reaching 0.772 (0.726–0.818). Of the three tests assessed, the predictive accuracies of PFA and LTA were satisfying for aspirin secondary prevention, while TEG's performance was poor. Only PFA could provide accurate prognostic information for bleeding. [ABSTRACT FROM AUTHOR]

Aims: We aimed to determine whether preprocedural renal function affects the outcome of acute ischemic stroke (AIS) patients with mechanical thrombectomy (MT) and whether this effect is modified by the onset‐to‐reperfusion time (OTR) and mediated by collateral status. Methods: Eligible patients with anterior circulation large vessel occlusion (LVO) who underwent MT between August 2018 and August 2020 were reviewed. The main outcome was good functional outcome [defined as modified Rankin Scale (mRS) of 0–2] at 3 months. Multivariable logistic regression analyses were conducted to explore the relationship between renal function and good functional outcome. A moderation analysis and the Johnson‐Neyman technique were performed to assess the interaction between renal function and OTR to predict the outcome of AIS patients with MT. Results: Among 100 enrolled patients, 36 (36%) exhibited good functional outcome. A decreased preprocedural estimated glomerular filtration rate (pre‐eGFR) was significantly associated with worse functional outcome [adjusted OR, 1.059 (1.012–1.108); p, 0.014], and this effect was partly mediated by collateral circulation. An interaction between OTR and pre‐eGFR on functional outcome was observed (P for interaction, 0.22), and pre‐eGFR only had a significant effect on functional outcome when OTR exceeded 455.8 min. Moreover, the adverse effect of OTR on functional outcome became no longer significant when the pre‐eGFR was higher than 89.0 mL/min/1.73 mL/min/1.73 m². Conclusions: Renal function was related to functional outcome at 3 months, and this relationship could be modified by OTR. The results suggested that reducing OTR and improving collateral circulation may mitigate the adverse effect of reduced kidney function on functional outcome. [ABSTRACT FROM AUTHOR]