- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Multifunctional N,S co-doped carbon dots for sensitive probing of temperature, ferric ion, and methotrexate
摘要： In this paper, we have presented a facile method to fabricate nitrogen and sulfur co-doped carbon dots (N,S-CDs) for blood methotrexate (MTX) sensing applications. The N,S-CDs with quantum yield up to 75% were obtained by one-step hydrothermal carbonization, using reduced glutathione and citric acid as the precursors. With this approach, the formation and the surface passivation of N,S-CDs were carried out simultaneously, resulting in intrinsic fluorescence emission. Owing to their pronounced temperature dependence of the fluorescence emission spectra, resultant N,S-CDs can work as versatile nanothermometry devices by taking advantage of the temperature sensitivity of their emission intensity. In addition, the obtained N,S-CDs facilitated high selectivity detection of Fe3+ ions with a detection limit as low as 0.31 μM and a wide linear range from 3.33 to 99.90 μM. More importantly, the added MTX selectively led to the fluorescence quenching of the N,S-CDs. Such fluorescence responses were used for well quantifying MTX in the range of 2.93 to 117.40 μM, and the detection limit was down to 0.95 μM. Due to Binert^ surface, the N,S-CDs well resisted the interferences from various biomolecules and exhibited excellent selectivity. The proposed sensing system was successfully used for the assay of MTX in human plasma. Due to simplicity, sensitivity, selectivity, and low cost, it exhibits great promise as a practical platform for MTX sensing in biological samples.
关键词： Hydrothermal carbonization,Doped carbon dots,Excitation-independent emission,Multifunctional probe,Methotrexate,Surface passivation
更新于2025-11-19 16:46:39
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Polarization independent quad-bandpass frequency selective surfaces with wide-band ratio
摘要： A single layer polarization independent quad-bandpass frequency selective surface (FSS) with wide-band ratio is demonstrated theoretically as well as experimentally. The proposed structure passes four frequency bands with wide band ratio. The proposed FSS design is implemented by incorporating alternate arrangement of four units which are rotated 90° clockwise to form a unit cell of metal over a FR4 substrate. The geometrical dimensions of proposed unit cell are optimized and arranged in such a way that the structure possesses the quad bandpass characteristic and aspect dimensions of one unit is 0.11λ × 0.11λ with respect to first resonant frequency. This FSS provides stable response for different angle of incidence in transverse electric (TE) mode and transverse magnetic (TM) mode. To validate the results proposed FSS array has been fabricated and measured in free space environment. The measured results are in good agreement with the simulated results. Excellent stability is also observed for different incident angle.
关键词： quad bandpass,polarization independent,frequency selective surface,band ratio
更新于2025-09-23 15:23:52
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Bipartite Bell inequalities with three ternary-outcome measurements—from theory to experiments
摘要： We explore quantum nonlocality in one of the simplest bipartite scenarios. Several new facet-defining Bell inequalities for the {[3,3,3],[3,3,3]} scenario are obtained with their quantum violations analyzed in details. Surprisingly, all these inequalities involving only genuine ternary-outcome measurements can be violated maximally by some two-qubit entangled states, such as the maximally entangled two-qubit state. This gives further evidence that in analyzing the quantum violation of Bell inequalities, or in the application of the latter to device-independent quantum information processing tasks, the commonly held wisdom of equating the local Hilbert space dimension of the optimal state with the number of measurement outcomes is not necessarily justifiable. In addition, when restricted to the minimal qubit subspace, it can be shown that one of these Bell inequalities requires non-projective measurements to attain maximal quantum violation, thereby giving the first example of a facet-defining Bell inequality where a genuine positive-operator-valued measure is relevant. We experimentally demonstrate the quantum violation of this and two other Bell inequalities for this scenario using energy–time entangled photon pairs. Using the obtained measurement statistics, we demonstrate how characterization of the underlying resource in the spirit of device-independence, but supplemented with auxiliary assumptions, can be achieved. In particular, we discuss how one may get around the fact that, due to finite-size effects, raw measurement statistics typically violate the non-signaling condition.
关键词： quantum nonlocality,device-independent quantum information,POVM,Bell inequalities
更新于2025-09-23 15:23:52
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Efficient scheme for passive decoy-state reference-frame-independent quantum key distribution
摘要： Reference-frame-independent quantum key distribution (RFI-QKD) has been demonstrated to be reliable and useful both in theories and experiments, which is intrinsically robust against slowly varying reference frames. In this paper, we propose an efficient scheme of passive decoy-state RFI-QKD based on the parametric down-conversion source, where a beam splitter splits the idler pulses into four local detection events to improve the performance of RFI-QKD systems. In addition, we demonstrate the worst relative rotation of reference frames in our scheme. Simulation results show that our scheme can achieve good performance even at the worst-case scenario.
关键词： Quantum key distribution,Passive decoy-state,Reference-frame-independent
更新于2025-09-23 15:23:52
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Prediction of soil carbon levels in calcareous soils of Iran by mid-infrared reflectance spectroscopy
摘要： The objective of this study was to assess the predictive performance of midDRIFTS-PLSR models in quantifying total carbon (TC), total organic carbon (TOC), total inorganic carbon (TIC), total nitrogen (TN), hot water extractable carbon and nitrogen (CHWE, NHWE), pH, and the clay, silt, and sand content of soils. A total of 68 soil samples were taken across an agroecological region in southwest Iran, and analyzed in the laboratory using mid-DRIFTS-PLSR. midDRIFTS-PLSR calibration models were developed, and external validation was performed for each of the soil properties via an independent algorithm. The calibration and validation models allowed for a sufficient prediction of TC, TIC, and TOC with residual prediction deviations ≥3 and R2 values >0.9. The precise prediction of carbon fractions, such as TC, TIC, and TOC, in a rapid and inexpensive manner confirmed that midDRIFTS analysis was a rapid-throughput and cost-effective technique for monitoring soil carbon at the regional scale.
关键词： Calibration,midDRIFTS,predict,soil carbon,independent
更新于2025-09-23 15:23:52
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[IEEE 2018 10th International Conference on Intelligent Human-Machine Systems and Cybernetics (IHMSC) - Hangzhou (2018.8.25-2018.8.26)] 2018 10th International Conference on Intelligent Human-Machine Systems and Cybernetics (IHMSC) - SAR and Optical Image Registration Method Based on Quantum Particle Swarm Optimization
摘要： Abstract: In the most important step of GIS and optical image fusion, in order to improve the registration accuracy and efficiency of the strategic target, a new image registration method based on quantum particle swarm optimization (QPSO) with independent optical selection is presented. The proposed method consists of three steps: first, it decomposes the optical image into different frequency components with the wavelet transform; second, it extracts the feature corner points with the Harris corner detector; and finally, it constructs the similarity measure by combining the mutual information and the spatial distance, and uses the QPSO algorithm to search the optimal transformation parameters. The experimental results show that the proposed method is effective and feasible, it can achieve high accuracy and robustness for the low-frequency component of the optical image.
关键词： GIS Image,Image Registration,Independent Optical Selection,Quantum Particle Swarm Optimization,Optical Image
更新于2025-09-23 15:22:29
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A Simple Channel Independent Beamforming Scheme with Parallel Uniform Circular Array
摘要： In this letter, we consider a uniform circular array (UCA) based line-of-sight (LOS) multiple-input-multiple-output (MIMO) system, where the transmit and receive UCAs are parallel but non-coaxial with each other. We propose a simple channel independent beamforming scheme with fast symbol-wise maximum likelihood (ML) detection.
关键词： multiple-input-multiple-output (MIMO),channel independent beamforming,Uniform circular array (UCA),fast maximum likelihood (ML)
更新于2025-09-23 15:22:29
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Cell death mechanisms in a mouse model of retinal degeneration in Spinocerebellar ataxia 7
摘要： Spino-cerebellar ataxia type 7 (SCA7) is a polyglutamine (polyQ) disorder characterized by neurodegeneration of the brain, cerebellum, and retina caused by a polyglutamine expansion in ataxin 7. The presence of an expanded polyQ tract in a mutant protein is known to induce protein aggregation, cellular stress, toxicity, and finally cell death. However, the consequences of the presence of mutant ataxin7 in the retina and the mechanisms underlying photoreceptor degeneration remain poorly understood. In this study, we show that in a retinal SCA7 mouse model, polyQ ataxin7 induces stress within the retina and activates Muller cells. Moreover, Unfolded Protein Response and autophagy are activated in SCA7 photoreceptors. We have also shown that the photoreceptor death does not involve a caspase-dependent apoptosis but instead involves apoptosis inducing factor (AIF) and Leukocyte Elastase Inhibitor (LEI/L-DNase II). When these two cell death effectors are downregulated by their siRNA, a significant reduction of photoreceptor death is observed. These results highlight the consequences of polyQ protein expression in the retina and the role of caspase-independent pathways involved in photoreceptor cell death.
关键词： retina,toxicity,Spinocerebellar ataxia type 7,caspase-independent cell death,photoreceptors,polyglutamine disorder,autophagy,unfolded protein response
更新于2025-09-23 15:22:29
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Polarization-based plug-and-play measurement-device-independent quantum key distribution
摘要： Measurement-device-independent quantum key distribution (MDI-QKD) has received much attention, with the goal of overcoming all of the security loopholes caused by an imperfect detection system. We here propose a plug-and-play MDI-QKD (P&P MDI-QKD) scheme whereby an untrusted relay node, Charlie, owns a laser and sends photons to Alice and Bob. Alice (Bob) modulates the polarization of the incident photons and returns them to Charlie. Charlie uses a modified Bell state analyzer (BSA) to perform Bell state measurements (BSM). In comparison with the original version of MDI-QKD, our scheme exploits a single untrusted laser as the photon source. This makes the signal photons identical and enhances the Hong-Ou-Mandel effect. Second, because of the P&P structure, the setup can automatically eliminate the birefringence influence of the fibers, which makes the setup highly stable. Finally, our modified BSA can identify |Φ?+ and |Φ?? of four Bell states with polarization encoding but not |Ψ?+ and |Ψ??. Based on practical experimental parameters, a simulation showed that the maximum theoretical secure transmission distance could reach more 280 km.
关键词： Plug-and-play,Measurement-device-independent,Quantum cryptography,Quantum key distribution
更新于2025-09-23 15:22:29
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Measurement-device-independent and arbitrarily loss-tolerant verification of quantum steering
摘要： We propose a method to verify quantum steering for two-qubit states with an arbitrary amount of null results when both the steering and steered parties cannot be trusted. We converted the steering inequality proposed in a recent article [Phys. Rev. X 2, 031003 (2012)] to a corresponding measurement-device-independent steering criterion that depends on the heralding efficiency of the steering party, number of measurement settings, and imperfection of the state preparation. As a result, for a relative frequency of valid measurement outcomes ηH, the steering can be verified using a number of different measurement settings larger than 1/ηH and maximally entangled states. Furthermore, steerability is guaranteed as long as the measurement efficiency of the steered party is nonzero. Our result is useful for loss-tolerant and measurement-device-independent steering tasks.
关键词： two-qubit states,loss-tolerant,quantum steering,measurement-device-independent,heralding efficiency
更新于2025-09-23 15:22:29