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We report a method to enhance the sensitivity of coherent population trapping (CPT) magnetometers using a combination of left-handed and right-handed circularly polarized light phase-delay detection and a differential detection scheme. The approach can achieve a four third-fold enhancement of the CPT dispersion signal slope and a three-fold reduction in noises. The proposed method experimentally exhibits a four third-fold magnetic field resolution enhancement in CPT open-loop measurements, and the differential method could achieve a sensitivity of 1â p T/H z at 10â Hz and a sensitivity of 0.4â p T/H z at 50-100â Hz in the CPT closed-loop measurement, which is a four-fold sensitivity enhancement compared to the single-transmitted CPT magnetometer.
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Short-wavelength infrared photodetectors play a significant role in various fields such as autonomous driving, military security, and biological medicine. However, state-of-the-art short-wavelength infrared photodetectors, such as InGaAs, require high-temperature fabrication and heterogenous integration with complementary metal-oxide-semiconductor (CMOS) readout circuits (ROIC), resulting in a high cost and low imaging resolution. Herein, for the first time, a low-cost, high-performance, high-stable, and thin-film transistor (TFT) ROIC monolithic-integrated (Bi,Sb)2 Se3 alloy thin-film short-wavelength infrared photodetector is reported. The (Bi,Sb)2 Se3 alloy thin-film short-wavelength infrared photodetectors demonstrate a high external quantum efficiency (EQE) of 21.1% (light intensity of 0.76 µW cm-2 ) and a fast response time (3.24 µs). The highest EQE is about two magnitudes than that of the extrinsic photoconduction of Sb2 Se3 (0.051%). In addition, the unpackaged devices demonstrate high electric and thermal stability (almost no attenuation at 120 °C for 312 h), showing potential for in-vehicle applications that may experient such a high temperature. Finally, both the (Bi,Sb)2 Se3 alloy thin film and n-type CdSe buffer layer are directly deposited on the TFT ROIC (with a 64 × 64-pixel array) with a low-temperature process and the material identification and imaging applications are presented. This work is a significant breakthrough in ROIC monolithic-integrated short-wavelength infrared imaging chips.
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The pyroelectric effect is used in a wide range of applications such as infrared (IR) detection and thermal energy harvesting, which require the pyroelectric materials to simultaneously have a high pyroelectric coefficient and a low dielectric constant for high figures of merit. However, in conventional proper ferroelectrics, the positive correlation between the pyroelectric coefficient and the dielectric constant imposes an insurmountable challenge in upgrading the figures of merit. Here, we explored superior pyroelectricity in [(CH3)4N][FeCl4] (TMA-FC) and [(CH3)4N][FeCl3Br] (TMA-FCB) molecular ferroelectric plastic crystals, which could decouple this positive correlation due to the nature of improper polarization behavior. Therefore, TMA-FC and TMA-FCB derive a high pyroelectric coefficient and a low dielectric constant simultaneously, yielding record-high figures of merit around room temperature. Furthermore, the favorable plasticity enables ferroelectric crystals to attach surfaces with different shapes for device design and integration. More interestingly, the molecular ferroelectrics could be softened and reshaped at elevated temperatures without decay in pyroelectricity, making them recyclable for cost savings and e-waste reduction. Combined with the facile fabrication process, the findings of this work would open avenues for employing molecular ferroelectric plastic crystals in the manufacture of high-performance pyroelectric devices.
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By arranging fluorophores in a directional way on a 2D DNA nanosheet that transfers energy from the initial donor to the acceptor through homogeneous Förster resonance energy transfer (homo-FRET), it is found that the photonic wires (PWs) based on cascade long-range resonance energy transfer (LrRET) up to 15.6 nm can be effectively achieved through the rational selection of the fluorophores and the adjustment of their position with different distance. Then, logic control of directional energy transfer is achieved with the blocking of the energy transfer pathway, making two tumor-associated microRNA (miRNA) inputs produce an obvious output with the association of tumor diagnosis only when they present simultaneously. This research provides a new thought for development of PWs on 2D DNA nanosheets and a smart application of LrRET-based DNA AND logic control of intracellular miRNA imaging and tumor cells recognition.
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Transferencia Resonante de Energía de Fluorescencia , MicroARNs , ADN , Fotones , LógicaRESUMEN
We report an efficient and straightforward method to synthesize enantio-enriched N-unprotected α-amino acetals via ruthenium-catalyzed direct asymmetric reductive amination. The α-amino acetal products are versatile and valuable platform molecules that can be converted to the corresponding α-amino acids, amino alcohols, and other derivatives by convenient transformations.
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In this work, homo-FRET (Förster resonance energy transfer between the same kind of fluorophores) takes place in a hetero-FRET (FRET between two different fluorophores) system and can effectively improve the energy transfer efficiency. Herein, a novel ratiometric fluorescence method was developed for the detection of nuclease activity. Exonuclease III (Exo III), an enzyme which has a high exodeoxyribonuclease activity for double-stranded DNA (dsDNA) in the 3' to 5' direction, was chosen as a proof of concept of this strategy. In a linear dsDNA template, the occurrence of homo-FRET in two Cy3 donors enables the highly efficient transfer of energy to the Cy5 acceptor. The ratio of fluorescence intensity between Cy3 and Cy5 (FD/FA) increases in an Exo III concentration-dependent manner, which built the foundation of Exo III quantification. This method exhibits a linear range from 0.25 to 8 U mL-1 with a detection limit of 0.17 U mL-1. Importantly, this platform also shows the potential for screening Exo III inhibitors and detecting Exo III activity in complex samples.
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Exodesoxirribonucleasas , Transferencia Resonante de Energía de Fluorescencia , Exodesoxirribonucleasas/metabolismo , Colorantes Fluorescentes , Espectrometría de FluorescenciaRESUMEN
Kudiezi injection was a commonly used drug in clinical practice, contained many components and was complex in structure. In order to effectively control the quality of traditional Chinese medicine, the study established a systematic research strategy for the first time. Through the UPLC-Q-TOF/MS technology analysis, 35 chemical components in Kudiezi injection were obtained, including four major categories. Moreover, the the quantitative methods of flavonoids by HPLC and organic acids by UPLC-MS/MS were established. A variety of chromatographic techniques, with good precision, sensitivity, repeatability and solution stability were applied to the analysis of 10 batches of Kudiezi injection. Therefore, the quality control of Kudiezi injection was a reliable and effective method, which can provide ideas for the qualitative and quantitative study of chemical constituents in other complex Chinese medicines.
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Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos , Espectrometría de Masas en Tándem/métodos , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/normas , Flavonoides/análisis , Medicina Tradicional China , Control de Calidad , Proyectos de InvestigaciónRESUMEN
The garnet Li7La3Zr2O12 (LLZO) has been widely investigated because of its high conductivity, wide electrochemical window, and chemical stability with regards to lithium metal. However, the usual preparation process of LLZO requires high-temperature sintering for a long time and a lot of mother powder to compensate for lithium evaporation. In this study submicron Li6.6La3Zr1.6Nb0.4O12 (LLZNO) powder-which has a stable cubic phase and high sintering activity-was prepared using the conventional solid-state reaction and the attrition milling process, and Li stoichiometric LLZNO ceramics were obtained by sintering this powder-which is difficult to control under high sintering temperatures and when sintered for a long time-at a relatively low temperature or for a short amount of time. The particle-size distribution, phase structure, microstructure, distribution of elements, total ionic conductivity, relative density, and activation energy of the submicron LLZNO powder and the LLZNO ceramics were tested and analyzed using laser diffraction particle-size analyzer (LD), X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Electrochemical Impedance Spectroscopy (EIS), and the Archimedean method. The total ionic conductivity of samples sintered at 1200 °C for 30 min was 5.09 × 10-4 S·cm-1, the activation energy was 0.311 eV, and the relative density was 87.3%. When the samples were sintered at 1150 °C for 60 min the total ionic conductivity was 3.49 × 10-4 S·cm-1, the activation energy was 0.316 eV, and the relative density was 90.4%. At the same time, quasi-solid-state batteries were assembled with LiMn2O4 as the positive electrode and submicron LLZNO powder as the solid-state electrolyte. After 50 cycles, the discharge specific capacity was 105.5 mAh/g and the columbic efficiency was above 95%.
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BACKGROUND: Considering that the quality control indicators in Chinese medicine (CM) are disconnected from safety and effectiveness, Prof. Chang-xiao Liu et al. has proposed a concept regarding the quality marker (Q-marker) of CM to promote the healthy development of the CM industry and improve the CM quality control method. PURPOSE: In this study, we proposed a strategy to discover and verify the toxicity Q-marker of CM based on network toxicology. METHODS: First, traditional biochemical pathology indicators and sensitive biomarkers were used to predict the toxicity of CM. Next, the chemical composition of toxic CMs and their metabolites were rapidly identified by multidimensional detection techniques. Subsequently, the interaction network between "toxicity - toxic chemical composition - toxic target - effect pathway" was built through network toxicology, and the potential toxicity Q-marker of CM was initially screened. Finally, the chemical properties of toxicity Q-markers were verified by traceability and testability. RESULTS: Based on the predicted results of network toxicology, the toxic compounds of CM were preliminarily identified, and the toxic mechanism was comprehensively interpreted. In the context of definite biological properties and chemical properties, the toxicity Q-marker was finally confirmed. CONCLUSION: This extensive review provides a study method for the toxicity Q-marker of CM, which helps to systemically and thoroughly reveal the internal toxicity mechanism of CM. The in-depth study of the toxicity Q-marker provides the material basis and technical support for the safety evaluation of CM.
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Biomarcadores/análisis , Medicamentos Herbarios Chinos/farmacología , Medicina Tradicional China/normas , Humanos , Medicina Tradicional China/efectos adversos , Control de CalidadRESUMEN
Fingerprinting is widely and commonly used in the quality control of traditional Chinese medicine (TCM) injections. However, current studies informed that the fingerprint similarity evaluation was less sensitive and easily generated false positive results. For this reason, a novel and practical chromatographic "Fingerprint-ROC-SVM" strategy was established by using KuDieZi (KDZ) injection as a case study in the present article. Firstly, the chromatographic fingerprints of KDZ injection were obtained by UPLC and the common characteristic peaks were identified with UPLC/Q-TOF-MS under the same chromatographic conditions. Then, the receiver operating characteristic (ROC) curve was used to optimize common characteristic peaks by the AUCs value greater than 0.7. Finally, a support vector machine (SVM) model, with the accuracy of 97.06%, was established by the optimized characteristic peaks and applied to monitor the quality of KDZ injection. As a result, the established model could sensitively and accurately distinguish the qualified products (QPs) with the unqualified products (UPs), high-temperature processed samples (HTPs) and high-illumination processed samples (HIPs) of KDZ injection, and the prediction accuracy was 100.00%, 93.75% and 100.00%, respectively. Furthermore, through the comparison with other chemometrics methods, the superiority of the novel analytical strategy was more prominent. It indicated that the novel and practical chromatographic "Fingerprint-ROC-SVM" strategy could be further applied to facilitate the development of the quality analysis of TCM injections.