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Owing to geometrical frustration in the kagome lattice, Mn3Sn displays a 120° in-plane triangular antiferromagnetic order, a manifestation of exchange interaction within the Heisenberg model. Here, we show the formation of a tunable noncoplanar magnetic ground state stabilized by higher-order exchange interactions in electron-doped Mn3Sn samples. Our density Functional Theory calculations reveal that the higher-order exchange induces a partial out-of-plane alignment of the Mn moments, resulting in a canted magnetic state, further experimentally confirmed by neutron diffraction study along with 60 T magnetic and Hall resistivity measurements. Interestingly, we find a large scalar spin chirality-induced Hall signal depending on the degree of non-coplanarity of the Mn moments. Additionally, we demonstrate simultaneous manipulation of two-component order-parameter in the system, where the two Hall signals can be independently manipulated. The present study explores the quantum phenomena associated with the coexistence of multiple magnetic orders and their prospective use in spintronic devices. [ABSTRACT FROM AUTHOR]

The successful realization of skyrmion-based spintronic devices depends on the easy manipulation of underlying magnetic interactions in the skyrmion-hosting materials. Although the mechanism of skyrmion formation in non-centrosymmetric magnets is comprehensively established, the stabilization process of different skyrmion-like magnetic textures in centrosymmetric magnets needs further investigation. Here, we utilize Lorentz transmission electron microscopy study to report the finding of a tunable skyrmion lattice up to room temperature in a centrosymmetric kagome ferromagnet Mn4Ga2Sn. We demonstrate that a controlled switching between the topological skyrmions and non-topological type-II magnetic bubbles can be realized at the optimal magnetic anisotropy. We find that the topological skyrmions are the energetically most stable magnetic objects in the centrosymmetric hexagonal magnets, whereas application of in-plane magnetic field stabilizes type-II magnetic bubbles as an excited state. The present study is a significant step towards understanding of the skyrmion stabilization mechanism in centrosymmetric materials for their future applications. Skyrmions are vortex-like magnetic textures typically observed in non-centrosymmetric systems, i.e. those with no centre of inversion. Here, using Lorentz transmission electron microscopy supported with micromagnetic simulations the authors report the observation of skyrmion lattices in the centrosymmetric kagome ferromagnet Mn4Ga2Sn, where a controlled switching between the topological skyrmions and non-topological type-II magnetic bubbles can be realized by manipulating the in-plane magnetic field at the optimal magnetic anisotropy. [ABSTRACT FROM AUTHOR]

Aldrin-induced stimulation of locomotor activity (LA) under nontolerant conditions was restored to control value after 20 or more consecutive days of aldrin administration. In contrast to the inhibition of GABAergic activity with aldrin under short-term conditions as observed in our previous study, the measurement of steady-state level of GABA, the activities of its metabolizing enzymes, turnover and the specific binding of GABA to its receptor in different regions of the brain of rats treated with aldrin (2 or 5 mg/kg/day, po) under long-term (for 30 consecutive days) conditions showed no change in the GABAergic activity in any regions of the rat brain. Moreover, the studies of the interaction between neurotransmitters (using agonist(s) and antagonist(s) of the respective neurotransmitter receptors) showed that long-term administration of aldrin restored the LA to control value by upregulation of central GABAergic activity through the interaction with dopaminergic and cholinergic systems. Thus, this result suggests that long-term aldrin exposure upregulated the central GABAergic activity inhibition under short-term aldrin treatment which may be a cause of restoration of LA stimulated by the short-term aldrin administration to its control value.