Combination of White Matter Hyperintensity and Neutrophil-to-Lymphocyte Ratio Predicts Short-Term Prognosis of Acute Ischemic Stroke Patients.

Purpose: To assess the value of combination of white matter hyperintensity (WMH) and neutrophil-to-lymphocyte ratio (NLR) in predicting short-term prognosis of acute ischemic stroke (AIS) patients.

Patients And Methods: Three hundred and nine AIS patients were included in this prospective observational research. They were evaluated at 3-month after the onset of AIS using modified Rankin Scale (mRS) score.

Enhancing the sensitivity of spin-exchange relaxation-free magnetometers using phase-modulated pump light with external Gaussian noise.

An optical pumping scheme is proposed for reducing the gradient of electron spin polarization and suppressing light source noise in a spin-exchange relaxation-free magnetometer. This is achieved by modulating only the phase of a narrow-linewidth pump light field with external Gaussian noise. Compared to the absence of phase modulation, the uniformity of electron spin polarization was improved by over 40%, and the light-frequency noise suppression ratio of the magnetometer was enhanced by 4.

Application of magnetoencephalography in epilepsy.

Magnetoencephalography (MEG) is a non-invasive neuroimaging technique that can detect whole-brain neuroelectromagnetic signals in real-time in a single measurement. Due to excellent temporal and spatial resolution and integration of computed tomography or magnetic resonance imaging data, MEG allows signal source analysis. It can pinpoint epileptic foci as well as functional brain regions, reducing the necessity for invasive electrode implantation.

High sensitivity closed-loop Rb optically pumped magnetometer for measuring nuclear magnetization.

Rb optically pumped magnetometer (OPM) based on electron paramagnetic resonance (EPR) show advantages to measure the nuclear magnetization and have succeeded in fundamental physics and rotation sensing, etc. The magnetometry sensitivity is a key performance of these Rb OPMs which should be improved. In this study, a high sensitivity Rb OPM is demonstrated theoretically and experimentally.

Demonstration of a high-density alkali-metal atomic magnetometer based on the frequency-symmetrical detuning effect of two pumping lights.

The existence of an approximately uniform and unsaturated electron spin polarization distribution within a high-density alkali-metal vapor is considered of great importance for significantly improving the response amplitude and sensitivity properties of an atomic magnetometer. However, when a high-density alkali-metal vapor is formed, the optical depth is much larger than the value of one, resulting in the electron spin polarization gradient. In this work, it was demonstrated from both numerical simulations and experimental points of view, that by replacing the resonant pumping light with two off-resonant pumping light sources, the signal amplitude of the magnetometer can be doubled.

Analysis and Measurement of Differential-Mode Magnetic Noise in Mn-Zn Soft Ferrite Shield for Ultra-Sensitive Sensors.

The magnetic noise generated by the ferrite magnetic shield affects the performance of ultra-sensitive atomic sensors. Differential measurement can effectively suppress the influence of common-mode (CM) magnetic noise, but the limit of suppression capability is not clear at present. In this paper, a finite element analysis model using power loss to calculate differential-mode (DM) magnetic noise under a ferrite magnetic shield is proposed.

A High-Performance Magnetic Shield with MnZn Ferrite and Mu-Metal Film Combination for Atomic Sensors.

This study proposes a high-performance magnetic shielding structure composed of MnZn ferrite and mu-metal film. The use of the mu-metal film with a high magnetic permeability restrains the decrease in the magnetic shielding coefficient caused by the magnetic leakage between the gap of magnetic annuli. The 0.

Analysis of effects of magnetic field gradient on atomic spin polarization and relaxation in optically pumped atomic magnetometers.

The magnetic field gradient within optical pumping magnetometers (OPMs) suppresses sensitivity improvement. We investigated the effects of the magnetic field gradient along the x-, y-, and z-axes on the limiting factors of magnetometers under extremely low magnetic field conditions. We modified the magnetic field gradient relaxation model such that it can be applied to atoms in the spin exchange relaxation free (SERF) regime.

Optimization of beam shaping for ultrasensitive inertial measurement using a phase-only spatial light modulator.

This study proposes an approach to generate a uniform flat-top beam with a liquid crystal spatial light modulator (LC-SLM) to optimize ultrasensitive inertial measurement. The random incomplete Gaussian beam is modulated into a flat-top beam by uploading a beam shaping optimization algorithm on an LC-SLM. Simulation results verify the effectiveness of the proposed method.

High spatial resolution multi-channel optically pumped atomic magnetometer based on a spatial light modulator.

Ultra-sensitive multi-channel optically pumped atomic magnetometers based on the spin-exchange relaxation-free (SERF) effect are powerful tools for applications in the field of magnetic imaging. To simultaneously achieve ultra-high spatial resolution and ultra-high magnetic field sensitivity, we proposed a high-resolution multi-channel SERF atomic magnetometer for two-dimensional magnetic field measurements based on a digital micro-mirror device (DMD) as the spatial light modulator for a single vapor cell. Under the optimal experimental conditions obtained via spatial and temporal modulation of the probe light, we first demonstrated that the average sensitivity of the proposed 25-channel magnetometer was approximately 25fT/Hz with a spatial resolution of 216µm.

Acousto-optic modulation detection method in an all-optical K-Rb hybrid atomic magnetometer using uniform design method.

An acousto-optic modulation (AOM) detection method is demonstrated to detect the atomic Larmor precession frequency in an all-optical K-Rb atomic magnetometer operated in Spin-Exchange Relaxation Free (SERF) regime. Magnetic field sensitivity of 14 fT/Hz was achieved by employing the uniform design (UD) [Acta Math Appl Sin.3, 363 (1980)] and subsequently optimizing the AOM modulation conditions.