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The increasing usage of general anesthetics on young children and infants has drawn extensive attention to the effects of these drugs on cognitive function later in life. Recent animal studies have revealed improvement in hippocampus-dependent performance after lower concentrations of sevoflurane exposure. However, the long-term effects of low-dose sevoflurane on the developing brain remain elusive. On postnatal day (P) 7, rats were treated with 1.2% sevoflurane (1.2% sevo group), 2.4% sevoflurane (2.4% sevo group), and air control (C group) for 6 h. On P35-40, rats' hippocampus-dependent learning and memory was tested using the Morris water maze. Cognition-related and synapse-related proteins in the hippocampus were measured using Western blotting on P35. On the same day, neurogenesis and synapse ultrastructure were evaluated using immunofluorescence and transmission electron microscopy (TEM). On P35, the rats neonatally exposed to 1.2% sevoflurane showed better behavioral results than control rats, but not in the 2.4% sevo group. Exposure to 1.2% sevoflurane increased the number of 5'-bromo-2-deoxyuridine (BrdU)-positive cells in the dentate gyrus and improved both synaptic number and ultrastructure in the hippocampus. The expression levels of BDNF, TrkB, postsynaptic density (PSD)-95, and synaptophysin in the hippocampus were also increased in the 1.2% sevo group. In contrast, no significant changes in neurogenesis or synaptic plasticity were observed between the C group and the 2.4% sevo group on P35. These results showed that exposure of the developing brain to a low concentration of sevoflurane for 6 h could promote spatial learning and memory function, along with increased hippocampal neurogenesis and synaptic plasticity, in later life.

With the resurgence of head-mounted displays for virtual reality, users need new input devices that can accurately track their hands and fingers in motion. We introduce Finexus, a multipoint tracking system using magnetic field sensing. By instrumenting the fingertips with electromagnets, the system can track fine fingertip movements in real time using only four magnetic sensors. To keep the system robust to noise, we operate each electromagnet at a different frequency and leverage bandpass filters to distinguish signals attributed to individual sensing points. We develop a novel algorithm to efficiently calculate the 3D positions of multiple electromagnets from corresponding field strengths. In our evaluation, we report an average accuracy of 1.33 mm, as compared to results from an optical tracker. Our real-time implementation shows Finexus is applicable to a wide variety of human input tasks, such as writing in the air.

We report a comprehensive high-pressure study on the monoclinic TlFeSe2 single crystal, which is an antiferromagnetic insulator with quasi-one-dimensional crystal structure at ambient pressure. It is found that TlFeSe2 undergoes a pressure-induced structural transformation from the monoclinic phase to an orthorhombic structure above P c ≈ 13 GPa, accompanied with a large volume collapse of ΔV/V 0 = 8.3%. In the low-pressure monoclinic phase, the insulating state is easily metallized at pressures above 2 GPa; while possible superconductivity with T c onset ∼ 2 K is found to emerge above 30 GPa in the high-pressure phase. Such a great tunability of TlFeSe2 under pressure indicates that the ternary AFeSe2 system (A = Tl, K, Cs, Rb) should be taken as an important platform for explorations of interesting phenomena such as insulator-metal transition, dimensionality crossover, and superconductivity.