We present in this paper a Herriott-cavity-assisted closed-loop Xe isotope gas comagnetometer. In this system, \(^{129}\)Xe and \(^{131}\)Xe atoms are pumped and probed by polarized Rb atoms, and ...continuously driven by oscillating magnetic fields, whose frequencies are kept on resonance by phase-locked loops (PLLs). Different from other schemes, we use a Herriott cavity to improve the Rb magnetometer sensitivity instead of the parametric modulation method, and this passive method is aimed to improve the system stability while maintaining the sensitivity. This system has demonstrated an angle random walk (ARW) of 0.06 \(^\circ\)/h\(^{1/2}\), and a bias instability of 0.2 \(^\circ\)/h (0.15 \(\mu\)Hz) with a bandwidth of 1.5 Hz. By adding a closed-loop Rb isotope comagnetometer, we can extend this system to dual simultaneously working comagnetometers sharing the same cell. This extended system has wide applications in precision measurements, where we can simultaneously and independently measure the coupling of anomalous fields with proton spin and neutron spin.
To investigate the role of Ara-C in regulating anti-CD3/anti-Pgp mediating T-lymphocytes activities against multi-drug resistant leukemia cells.
The diabody of anti-CD3/anti-Pgp was purified by E-tag ...affinity chromatography. K562 and K562/A02 cells were treated with Ara-C. The expressions of B7-1 and B7-2 on K562 and K562/AO2 cells were detected by FACS. The cytotoxicity of T-lymphocytes combined with anti-CD3/anU-Pgp plus Ara-C was analyzed by CytoTox 96 nonradioactive method.
The expressions of B7-1 and B7-2 on K562 and K562/A02 cells treated by Ara-C was significantly higher than those untreated. The effect/target ratio was from 0.39:1 to 25:1, and the killing rate of activated T cells to anti-drug-resistant leukemia cells was from (16.44 +/- 1.20)% to (60.49 +/- 2.90)%. The killing rates were increased gradually, with both the effect/target ratio and the antibody concentration increasing (P < 0.05).
Ara-C may be an important adjuvant for improving anti-CD3/anti-Pgp mediating T-lymphocytes activities again
To establish a three-step purification method of preparative-scale antiCD20 (Fab')2 using AKTA prime.
AntiCD20 (Fab')2 was extracted by hyperosmotic solution and then purified by CM sepharose FF, ...phenyl sepharose FF, and protein G sepharose FF.
Around 8 mg anti-CD20 (Fab')2, whose purification was 96.678%, was purified. The antigen-binding activity of antiCD20 (Fab')2 was similar to that of antiCD20 (Fab')2 purified by protein G sepharose FF and S-100.
The three-step purification method can obtain high-purity preparative-scale antiCD20 (Fab')2 in a simple way.
To explore the toxicological mechanism of hydroquinone in human bronchial epithelial cells and to investigate whether DNA polymerase beta is involved in protecting cells from damage caused by ...hydroquinone.
DNA polymerase beta knock-down cell line was established via RNA interference as an experimental group. Normal human bronchial epithelial cells and cells transfected with the empty vector of pEGFP-C1 were used as controls. Cells were treated with different concentrations of hydroquinone (ranged from 10 micromol/L to 120 micromol/L) for 4 hours. MTT assay and Comet assay single-cell gel electrophoresis (SCGE) were performed respectively to detect the toxicity of hydroquinone.
MTT assay showed that DNA polymerase beta knock-down cells treated with different concentrations of hydroquinone had a lower absorbance value at 490 nm than the control cells in a dose-dependant manner. Comet assay revealed that different concentrations of hydroquinone caused more severe DNA damage in DNA polymerase beta knock-down cell line than in control cells and there was no significant difference in the two control groups.
Hydroquinone has significant toxicity to human bronchial epithelial cells and causes DNA damage. DNA polymerase beta knock-down cell line appears more sensitive to hydroquinone than the control cells. The results suggest that DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone.
In the mol-ecule of the title compound, C(14)H(16)N(2)O(3), the dihedral angle between the pyridyl rings is 87.74 (3)°. In the crystal structure, inter-molecular C-H⋯O hydrogen bonds link the ...mol-ecules into infinite zigzag chains.
Balance dysfunctions in stroke survivors are common and have significant impact on functional independence and rehabilitation. As a crucial technique of Traditional Chinese Medicine, acupuncture has ...been used widely for balance dysfunctions after stroke, although its effective evidence is not clear. Hence, we plan this systematic review protocol to evaluate the value of its efficacy and safety for balance dysfunctions after stroke.
We will search the databases from the publishment to April 2018: Web of Science, PubMed, Medline, Cochrane Library, EBASE, WHO International Clinical Trials Registry Platform, Wanfang, Chinese Biomedical Literature Database, Chinese Scientific Journal Database (VIP), and China National Knowledge Infrastructure. The clinical efficacy will be accepted as the primary outcomes. RevMan V.5.3 software will be used to compute the data synthesis when a meta-analysis is allowed.
This systematic review and meta-analysis will provide a high-quality synthesis of current evidence of acupuncture for balance dysfunctions after stroke including clinical efficacy, balance ability, walking ability, and activity of daily life etcetera.
This protocol will determine whether acupuncture is an effective and safety intervention for balance dysfunctions after stroke.
Detecting microwave signals over a wide frequency range has numerous advantages as it enables simultaneous transmission of a large amount of information and access to more spectrum resources. This ...capability is crucial for applications such as microwave communication, remote sensing, and radar. However, conventional microwave receiving systems are limited by amplifiers and band-pass filters that can only operate efficiently in a specific frequency range. Typically, these systems can only process signals within a three-fold frequency range, which limits the data transfer bandwidth of the microwave communication systems. Developing novel atom-integrated microwave sensors, for example, radio frequency (RF)-chip coupled Rydberg atomic receiver, provides opportunities for a large working bandwidth of microwave sensing at the atomic level. Here, an ultra-wide dual-band RF sensing scheme is demonstrated by space-division multiplexing two RF-chip-integrated atomic receiver modules. The system can simultaneously receive dual-band microwave signals that span a frequency range exceeding 6 octaves (300 MHz and 24 GHz). This work paves the way for multi-band microwave reception applications within an ultra-wide range by RF-chip-integrated Rydberg atomic sensor.
The development of artificial receptors that combine ultrahigh‐affinity binding and controllable release for active guests holds significant importance in biomedical applications. On one hand, a ...complex with an exceedingly high binding affinity can resist unwanted dissociation induced by dilution effect and complex interferents within physiological environments. On the other hand, stimulus‐responsive release of the guest is essential for precisely activating its function. In this context, we expanded hydrophobic cavity surface of a hypoxia‐responsive azocalix4arene, affording Naph‐SAC4A. This modification significantly enhanced its aqueous binding affinity to 1013 M−1, akin to the naturally occurring strongest recognition pair, biotin/(strept−)avidin. Consequently, Naph‐SAC4A emerges as the first artificial receptor to simultaneously integrate ultrahigh recognition affinity and actively controllable release. The markedly enhanced affinity not only improved Naph‐SAC4A′s sensitivity in detecting rocuronium bromide in serum, but also refined the precision of hypoxia‐responsive doxorubicin delivery at the cellular level, demonstrating its immense potential for diverse practical applications.
A hypoxia‐responsive azocalix4arene (Naph‐SAC4A) has been developed that can achieve a biotin/(strept−)avidin‐level binding affinity (up to 1013 M−1 ) through its expanded hydrophobic surface. Naph‐SAC4A demonstrated the sensitive recognition of rocuronium in serum and a hypoxia‐responsive delivery of doxorubicin with minimum leakage at the cellular level.
Engineering a Terahertz (THz) frequency comb spectroscopy at atomic level advances the precisely measurement in spectroscopy and sensing. Current progresses on THz frequency comb rely on ...difference-frequency generation, optical parametric oscillation, and other methods. Generating a THz frequency comb poses challenges in source stability and achieving a narrow bandwidth, which traditional THz devices are difficult to achieve. Furthermore, accurately measuring the generated THz frequency comb necessitates a high-performance THz detector. Rydberg atoms are well-suited for electric field sensing due to their ultra-wide radio frequency transition energy levels, making them especially sensitive to external electric fields in the DC to THz bandwidth. However, there have been no reports about generating THz frequency comb spectroscopy at the atomic level until now. This work presents a THz frequency comb spectroscopy with Rydberg atoms, in which a Floquet comb-like transition is engineered through a time-periodic drive field. Our approach simplifies the setup required for THz frequency comb spectroscopy while extending the working bandwidth for Rydberg atomic sensors. The THz frequency comb spectroscopy at the atomic level reported in this article shows great potential for various applications in astronomy, remote sensing, spectral detection of biological samples, and other related fields.
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