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1.
J Magn Reson ; 335: 107128, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34942575

ABSTRACT

Rb atom serves as both polarization medium and an in-situ magnetometer in a nuclear magnetic resonance gyroscope. Analytical solution for the in-situ magnetometer output is obtained. The output gains and the decoupling phases for the transverse fields are developed analytically. A method to determine experimentally the decoupling phases for the x and y outputs by scanning the phases at different offsets of the magnetometer is proposed. Influence of magnetic field parameters on the output gains and the decoupling phases are analyzed by experiment and theoretical computations. It is found that the main static field B0 and the sinusoidal carrier amplitude Bc and their ratios have significant effects on the output gains and decoupling phases. Accurate determination of the decoupling phases needs careful minimization of the constant residual field. The performance of the in-situ magnetometer is evaluated by experiment with the coupled output characteristic bellow ±0.16 nT when the transverse input field is within ±100 nT and the transverse output sensitivity 0.01nT/Hz0.5 within the bandwidth except the low frequency part.

2.
Rev Sci Instrum ; 91(9): 095005, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-33003795

ABSTRACT

In nuclear magnetic resonance gyroscopes (NMRGs), an ambient stray field should be suppressed to maximize performance of the in situ parametrically modulated alkali magnetometer (PMAM). Transfer functions of the PMAM of NMRGs decoupled with lock-in amplifiers are obtained by theoretical and simulation identification. It is found that the frequency bandwidth of the PMAM of NMRGs decoupled by lock-in amplifiers depends largely upon the low-pass filter of the lock-in amplifiers. A dynamic Kalman filter is used to estimate the stray field disturbance that is fed back to field coils to compensate the disturbance in the PMAM. Simulation and experiment results show that the dynamic Kalman filter has adaptiveness to the frequency shift of the nuclear spin precession signal of NMRGs that is quasi-sinusoidal. The dynamic Kalman filter for the PMAM is efficient in suppressing the ambient stray field noise of broad band and low frequency.

3.
International Journal of Surgery ; (12): 171-173, 2015.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-470941

ABSTRACT

Objective To evaluate the performance and feasibility of sentinel node biopsy(SNB) in male breast cancer patients using Methylthioninium Chloride Injection.Methods At the First Affiliated Hospital of Zhengzhou University,there are 11 patients in group from March 2010 to December 2014.The clinical stage was cT1-T2N0M0.All patients using Methylthioninium Chloride Injection as the tracer.11 patients are given with sentinel lymph node biopsy,while given the axillary lymph node dissection.Results In 11 cases of male breast cancer patients,10 cases obtained the sentinel lymph nodes,the detection rate was 90.9% (10/11).The sentinel lymph node is in 1-3,the average is 1.7 gold.Non sentinel lymph nodes are in 8-14,the average is 10.5 gold.The coincidence rate is 90.0% The sensitivity is 100% and The precision is 60%.Conclusions Sentinel lymph node biopsy can accurately predict the metastasis of axillary lymph node of breast cancer in male patients.

4.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-484222

ABSTRACT

Objective To predict the length of peripherally inserted central venous catheters(PICC) with electronic chest radiograph scale measurement techniques, and observe its clinical effect. Methods A total of 185 breast cancer patients from October 2012 to December 2013 who were treated by PICC combined with MST guided by ultrasonic technology were as control group. A total of 192 breast cancer patients from January to November 2014 were as observation group. Control group adopted from the puncture point to right sternoclavicular joints impreaaion nip down again to the third floor of PICC in vitro measurement method. Observation group used to right sternoclavicular joints from the puncture point plus right sternoclavicular joints to subcarinal 1 vertebral body length, right sternoclavicular joints to subcarinal 1 vertebral body length measurement by electronic chest radiograph scale technology directly measured from the electronic chest radiographs. The accuracy rates and complications between the two measurement methods were compared. Results The accuracy rate in observation group was 97.92%(188/192), which was higher than that in control group (68.11%,126/185 ),and there was significant differencek,χ2=60.15, P<0.01. The complication rate in observation group was 6.77%(13/192), which was lower than that in control group (20.54%, 38/185) ,and there was significant difference,χ2=9.58, P<0.01. Conclusions The electronic chest radiograph scale measurement techniques could effectively improve the accuracy of PICC catheter placed, improve the quality of venipuncture, decrease the complications .

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