Magnetic triangular bubble lattices in bismuth-doped yttrium iron garnet

Magnetic bubbles have again become a subject of significant attention following the experimental observation of topologically nontrivial magnetic skyrmions. In recent work, tailoring the shape of the bubbles is considered a key factor for their dynamics in spintronic devices. In addition to the reported circular, elliptical, and square bubbles, here we observe triangular bubble domains in bismuth-doped yttrium iron garnet(Bi-YIG) using Kerr microscopy. The bubble domains evolve from discrete circular to latticed triangular and hexagonal shapes. Further, the orientation of the triangular bubbles in the hexagonal lattices can be flipped by decreasing the magnetic field. The sixfold in-plane magnetic anisotropy of Bi-YIG(111) crystal, which is presumably the mechanism underlying the triangular shape of the bubbles, is measured as1179 erg/cm~3. The study of the morphologies of topologically trivial bubbles in YIG offers insight into nontrivial spin textures, which is appealing for future spintronic applications.

Morphine attenuates frustration-like behavior induced by sucrose reward deprivation in rats

In this study, a T-maze-based frustration model in rats was established using sucrose-reward deprivation, The results revealed that rats maintained a 75% preference for the sucrose-reward arm in the reward phase. During the sucrose-deprivation frustration phase, both the preference for the sucrose-deprivation arm （62.5%） and time spent waiting in the sucrose-deprivation arm decreased. Acute injection of morphine increased the preference in a dose-dependent fashion, and prolonged the waiting duration in the sucrose-deprivation arm. These findings indicate that morphine specifically inhibited the frustration response induced by sucrose reward deprivation. To further elucidate the pharmacological mechanisms involved, the opioid receptor antagonist naloxone was given to model rats prior to the injection of morphine. The results revealed that naloxone administration markedly attenuated the anti-frustration-like effects of 3 mg/kg morphine treatment. These findings suggest that morphine attenuates the frustration-like response to reward deprivation in rats through the opioid receptor.

Females adopt sexual catalepsy to facilitate mating

Theory predicts that males and females of dioecious species typically engage in an evolutionary sexual conflict over the frequency and choice of mating partner.Female sexual cannibalism,a particularly dramatic illustration of this conflict,is widespread in certain animal taxa including spiders.Nevertheless,females of some funnel weaving spiders that are generally aggressive to conspecifics enter a cataleptic state after male courtship,ensuring the males can mate without risk of attack.In this study,we demonstrated that the physical posture and duration,metabo-lites,and central neurotransmitters of females of Aterigena aculeata in sexual catalepsy closely resemble females in thanatosis but are distinct from those in anesthesia,indicating that the courted females feign death to eliminate the risk of potentially aggressive responses and thereby allow preferred males to mate.Unlike the taxonomically widespread thanatosis,which generally represents a deceptive visual signal that acts against the interest of the receivers,sexual catalepsy of females in the funnel weaving spiders may deliver a sexual-receptive signal to the courting males and thereby benefit both the signal senders and receivers.Therefore,sexual catalepsy in A.aculeata may not reflect a conflict butrather a confluence of interest betweenthe sexes.