Publications by authors named "Le-Le Chen"

Article Synopsis
  • A high-precision test of the spin- and velocity-dependent (SVD) interaction between spin-polarized protons and unpolarized nucleons is conducted using a Bragg atom interferometer with ^{87}Rb atoms.
  • The experiment enhances the precision of free fall measurements to 9.2×10^{-9}, significantly improving on earlier polarized atom experiments.
  • It also provides a new constraint on the SVD interaction coupling, indicating greater sensitivity and opening new avenues for studying physics with polarized-atom interferometers.
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Article Synopsis
  • - GeTe is a promising lead-free thermoelectric material that faces challenges with high carrier concentration and mobility due to Ge vacancy issues, prompting the use of aliovalent doping for optimization.
  • - A novel Trojan doping strategy using CuScTe improves carrier concentration and mobility without increasing charge carrier scattering, achieving better thermoelectric performance.
  • - This study demonstrates that the (GeSbTe)(CuScTe) alloy exhibits a significant Seebeck coefficient and low lattice thermal conductivity, enhancing thermoelectric efficiency with a figure of merit (ZT) of approximately 1.81 at 623 K.
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Objective: To observe the antipruritic effect and mechanism of the volatile oil of Zanthoxylum bungeanum and Zanthoxylum schinifolium on chronic eczema to provide data support for clinical application and new drug development of Zanthoxylum bungeanum and Zanthoxylum schinifolium.

Methods: The model of chronic eczema was established by using 2-dinitrochlorobenzene (DNCB), and the composition and content of volatile oil in Zanthoxylum schinifolium and Zanthoxylum bungeanum was determined by gas chromatography-mass spectrometry (GC-MS). The antipruritic effect by (EASI) score of eczema area and severity index and scratching times was then evaluated.

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Vibration correction provides a simple and flexible method of suppressing ambient vibration noise in transportable atom gravimeters. However, in the seismometers used for vibration correction, a spurious output may be induced by the magnetic field of the magnetic-optical trap, introducing errors to the gravity measurements. This paper evaluates the influence of the magnetic field on the seismometer and the corresponding errors in the gravity measurements.

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Background: Cardiac resynchronization therapy (CRT) could be considered for heart failure (HF) patients with atrial fibrillation (AF) unless a potent ventricular capture strategy is conducted. However, the benefit of a pacemaker (PM; as part of CRT) in patients with AF and whether atrioventricular junction (or nodal) ablation (AVAB) can improve the prognosis of these patients compared with those treated medically to support ventricular capture are unclear.

Methods And Results: Systematic reviews and meta-analyses investigating the roles of PMs and AVAB in patients with AF were obtained in a search of the PubMed, Embase, and Medline databases and then analyzed with respect to the following outcomes: mortality, left ventricular ejection fraction, and clinical findings including the New York Heart Association class, 6-min walk distance (6MWD), quality of life as assessed in a specific questionnaire, and response to CRT.

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The accuracy of atom gravimeters is directly related to the Raman laser, which is used to manipulate the atomic wave packet, and the frequency of the Raman laser could be affected by temperature when the laser polarization is not along the preferred axis of the electro-optic crystal employed in the modulation transfer spectrum (MTS). This effect has been researched by modulating the laser polarization in the MTS in this work. The experimental results show that both the laser frequency and gravity measurement results have a sinusoidal dependence on temperature, and the period of the fluctuation is 0.

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A compact laser system for a portable Rb atom interferometry gravimeter has been demonstrated in this work. This laser system is based on frequency doubling of a single seed laser at the wavelength of 1560 nm. The frequency of the seed laser is controlled by a digital unit with an analog feedback circuit.

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The vibration isolator usually plays an important role in atom interferometry gravimeters to improve their sensitivity. We show that the parasitic forced vibration of the Raman mirror, which is induced by external forces acting on the vibration isolator, can cause a bias in atom gravimeters. The mechanism of how this effect induces an additional phase shift in our interferometer is analyzed.

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An ultra-low frequency active vibration isolator, simultaneously suppressing three-dimensional vibration noise, is demonstrated experimentally. The equivalent natural period of the isolator is 100 s and 12 s for the vertical and horizontal direction, respectively. The vibration noise in the vertical direction is about 50 times reduced during 0.

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Objective: To observe the differences of therapeutic effect of spastic paralysis after stroke between electroacupuncture and acupuncture and explore the mechanism.

Methods: Sixty-four cases were randomly divided into an electroacupuncture group (n = 33) and an acupuncture group (n = 31). Both groups were treated with Bobath facilitation techniques and medicine treatments.

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