Integral precession calibration method of PIGA on linear vibration table

Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of Pendulous Integrating Gyro Accelerometer(PIGA).Integral precession calibration method is proposed to calibrate PIGA on a linear vibration table in this paper.Based on the precise expressions of PIGA’s inputs,the error calibration model of PIGA is established.Precession angular velocity errors of PIGA are suppressed by integer periodic precession and the errors caused by non-integer periods vibrating are compensated.The complete calibration process,including planning,preparation,PIGA testing,and coefficient identification,is designed to optimize the test operations and evaluate the calibration results.The effect of the main errors on calibration uncertainty is analyzed and the relative sensitivity function is proposed to further optimize the test positions.Experimental and simulation results verify that the proposed 10-position calibration method can improve calibration uncertainties after compensating for the related errors.The order of calibration uncertainties of the second-and third-order coefficients are decreased to 10^(-8)(rad.s^(-1))/g^(2)and 10^(-8)(rad.s^(-1))/g3,respectively.Compared with the other two classical calibration methods,the calibration uncertainties of PIGA’s nonlinear error coefficients can be effectively reduced and the proportional residual errors are decreased less than 3×10-6(rad.s^(-1))/g by using the proposed calibration method.

Correlation Analysis of Molecularly-Defined Cortical Interneuron Populations with Morpho-Electric Properties in Layer V of Mouse Neocortex

Cortical interneurons can be categorized into distinct populations based on multiple modalities,including molecular signatures and morpho-electrical(M/E)properties.Recently,many transcriptomic signatures based on single-cell RNA-seq have been identified in cortical interneurons.However,whether different interneuron populations defined by transcriptomic signature expressions correspond to distinct M/E subtypes is still unknown.Here,we applied the Patch-PCR approach to simultaneously obtain the M/E properties and messenger RNA(mRNA)expression of>600 interneurons in layer V of the mouse somatosensory cortex(S1).Subsequently,we identified 11 M/E subtypes,9 neurochemical cell populations(NCs),and 20 transcriptomic cell populations(TCs)in this cortical lamina.Further analysis revealed that cells in many NCs and TCs comprised several M/E types and were difficult to clearly distinguish morpho-electrically.A similar analysis of layer V interneurons of mouse primary visual cortex(V1)and motor cortex(M1)gave results largely comparable to S1.Comparison between S1,V1,and M1 suggested that,compared to V1,S1 interneurons were morpho-electrically more similar to M1.Our study reveals the presence of substantial M/E variations in cortical interneuron populations defined by molecular expression.