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Antiferromagnetic insulators have recently been proved to support spin current efficiently. Here, we report the dampinglike spin-orbit torque (SOT) in Pt/NiO/CoFeB has a strong temperature dependence and reverses the sign below certain temperatures, which is different from the slight variation with temperature in the Pt/CoFeB bilayer. The negative dampinglike SOT at low temperatures is proposed to be mediated by the magnetic interactions that tie with the "exchange bias" in Pt/NiO/CoFeB, in contrast to the thermal-magnon-mediated scenario at high temperatures. Our results highlight the promise to control the SOT through tuning the magnetic structure in multilayers.
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AIMS/INTRODUCTION: Women with gestational diabetes mellitus are at high risk for adverse maternal and neonatal outcomes. The study aimed to evaluate the performance of the triglyceride-glucose index in predicting the risk of developing adverse outcomes in women with gestational diabetes mellitus. MATERIALS AND METHODS: This retrospective multicenter cohort study included 8,808 pregnant women with gestational diabetes mellitus in two grade-A tertiary hospitals in China during 2018-2022. The triglyceride-glucose index was defined as ln [triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2]. Significant adverse gestational diabetes mellitus outcomes were chosen by generalized linear models as the main outcomes. Multivariable logistic regression models evaluated their association with the triglyceride-glucose index. Areas under the receiver operating characteristic curves predicted adverse pregnancy outcomes. The prediction efficiency was validated in the sensitivity analysis dataset and validation cohort. RESULTS: The triglyceride-glucose index was associated with preeclampsia, severe preeclampsia, preterm birth, placenta accreta spectrum, and macrosomia before and after adjusting for confounding factors (P < 0.05). The predictive performance of the triglyceride-glucose index was relatively moderate. Incorporating the triglyceride-glucose index into the baseline clinical risk model improved the area under curves for the diagnosis of preeclampsia (0.749 [0.714-0.784] vs 0.766 [0.734-0.798], P = 0.033) and macrosomia (0.664 [0.644-0.685] vs 0.676 [0.656-0.697], P = 0.002). These predictive models exhibited good calibration and robustness. CONCLUSIONS: The triglyceride-glucose index is positively associated with preeclampsia, severe preeclampsia, preterm birth, placenta accreta spectrum, and macrosomia and is useful for the early prediction and prevention of adverse outcomes in women with gestational diabetes mellitus.
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For the spin-to-charge conversion (SCC) in heavy metal/ferromagnet (HM/FM) heterostructure, the contribution of interfacial spin-orbit coupling (SOC) remains controversial. Here, we investigate the SCC process of the Pt/NiFe heterostructure by the spin pumping in YIG/Pt/NiFe/IrMn multilayers. Due to the exchange bias of NiFe/IrMn structure, the NiFe magnetization can be switched between magnetically unsaturated and saturated states by opposite resonance fields of YIG layer. The spin-pumping signal is found to decrease significantly when the NiFe magnetization is changed from the saturated state to the unsaturated state. Theoretical analysis indicates that the interfacial spin absorption is enhanced for the above-mentioned NiFe magnetic state change, which results in the increased and decreased spin flow in the Pt layer and across the Pt/NiFe interface, respectively. These results demonstrate that in our case the interfacial SOC effect at the Pt/NiFe interface is dominant over the bulk inverse spin Hall effect in the Pt layer. Our work reveals a significant role of interfacial SOC in the SCC in HM/FM heterostructure, which can promote the development of high-efficiency spintronic devices through interfacial engineering.