- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Visualization of carboxylesterase 2 with a near-infrared two-photon fluorescent probe and its potential evaluation of anticancer drug effects in orthotopic colon carcinoma mice model
摘要： We establish a near-infrared two-photon fluorescent probe for the detection of CE2 with high selectivity and sensitivity. This probe exhibits low cytotoxicity and superior tissue penetration ability for evaluating real-time activity of CE2 in living cells, in cancer tissues, and in colon carcinoma mice model.
关键词： anticancer drug effects,colon carcinoma,CE2,fluorescent probe,two-photon,near-infrared
更新于2025-09-19 17:13:59
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The implementation and data analysis of an interferometer for intense short pulse laser experiments
摘要： We present an interferometry setup and the detailed fringe analysis method for intense short pulse (SP) laser experiments. The interferometry scheme was re?ned through multiple campaigns to investigate the effects of pre-plasmas on energetic electrons at the Jupiter Laser Facility at Lawrence Livermore National Laboratory. The interferometer used a frequency doubled (λ = 0.527 μm) 0.5 ps long optical probe beam to measure the pre-plasma density, an invaluable parameter to better understand how varying pre-plasma conditions affect the characteristics of the energetic electrons. The hardware of the diagnostic, data analysis and example data are presented. The diagnostic setup and the analysis procedure can be employed for any other SP laser experiments and interferograms, respectively.
关键词： short pulse laser,optical interferometry,Mach–Zehnder interferometer,picosecond probe,plasma density
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Generation of radially polarized beams by intracavity waveguide technique
摘要： The development of base stations (BSs) with large aperture antenna arrays, enabled partially by the utilization of cmWave and mmWave frequency bands, will require radiated testing in fading conditions. In this paper, the objective is to investigate the suitable measurement distances and physical dimensions of the over-the-air setups for the performance evaluation of massive multiple-input multiple-output (MIMO) BSs in anechoic chambers with multiple probes. Setup dimension is the major cost factor in the test systems and is thus the key issue to be investigated. The purpose is to determine whether the conventional far field criteria must be followed when determining the range of the setup or if they can be relieved. The impact of limited test setup dimension on various metrics, e.g., far field criteria, field performance within the test area, system link budget analysis, direction of arrival estimation algorithm as well as multi-user MIMO sum-rate capacity are investigated to determine the range of the test setup. It was found that the link budget does not support for the measurement distances claimed by the Fraunhofer distance. Most of the utilized metrics, especially the sum rate capacity, indicate that smaller setup sizes can still yield reasonable measurement accuracy. Simulations were performed at 2.6, 3.5, and 28 GHz frequencies.
关键词： over the air testing,performance evaluation,Massive MIMO base station,multi-probe anechoic chamber setup.
更新于2025-09-19 17:13:59
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Cresyl violet as a new contrast agent in probe‐based confocal laser endomicroscopy for in vivo diagnosis of gastric intestinal metaplasia
摘要： Background and Aim: Cresyl violet (CV) is a topical dye that allows simultaneous chromoendoscopy and in vivo confocal laser endomicroscopy (CLE) in identification of neoplastic changes of the lower GI tract without intravenous injection of fluorescein, but as yet no investigation has reported its application in the diagnosis of gastric intestinal metaplasia (GIM). This study aims to assess the feasibility as well as diagnosis accuracy of topical CV for in vivo diagnosis of GIM by using probe-based confocal laser endomicroscopy (pCLE). Methods: In this prospective, open-label, feasibility study, 129 confocal videos from 22 patients with known GIM were analyzed and compared with corresponding histological images to establish the CV staining characteristics. In addition, 47 patients with known or suspected GIM were prospectively enrolled to evaluate the accuracy of this topical CV endomicroscopic imaging. Results: PCLE with topical CV enabled clear visualization of the goblet cells, absorptive cells and intestinal villi of GIM. The accuracy, sensitivity, specificity, positive and negative predictive value of pCLE diagnosis of GIM on a per-location analysis was 93.01%, 91.95%, 93.51%, 86.96%, and 96.11%, respectively. The ICC for inter-observer agreement and mean kappa value for intra-observer agreement for the diagnosis of GIM was 0.82 and 0.87, respectively. Conclusions: Topical CV enables real-time chromoendoscopy in conjunction with pCLE examination of the stomach and warrants accurate diagnosis of GIM. It may be an acceptable and potentially alternative dye for confocal imaging in the future.
关键词： gastric intestinal metaplasia,probe-based confocal laser endomicroscopy,Cresyl violet
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Evidence of enhanced Zn-diffusion observed during the growth of Inverted Metamorphic Solar Cells
摘要： We present novel waveguide packaging for sub-millimeter and terahertz-wave devices, which is suitable for large chip-width MMICs and doesn’t require any additional fabrication process. With full electromagnetic simulation, we analyze possible wave modes in a rectangular waveguide with thin E-plane slits formed for inserting large-width MMICs into the split waveguide block and show that parasitic modes can be well suppressed by lossy and high-dielectric material. For a 1.1-mm-wide test IC in the 260–320 GHz band, measured transition loss is around 1 dB with more than 60 dB inter-port isolation.
关键词： terahertz wave,waveguide package,Integrated E-plane probe
更新于2025-09-19 17:13:59
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Self‐Assembled Room Temperature Multiferroic BiFeO <sub/>3</sub> ‐LiFe <sub/>5</sub> O <sub/>8</sub> Nanocomposites
摘要： Multiferroic materials have driven significant research interest due to their promising technological potential. Developing new room-temperature multiferroics and understanding their fundamental properties are important to reveal unanticipated physical phenomena and potential applications. Here, a new room temperature multiferroic nanocomposite comprised of an ordered ferrimagnetic spinel α-LiFe5O8 (LFO) and a ferroelectric perovskite BiFeO3 (BFO) is presented. It is observed that lithium (Li)-doping in BFO favors the formation of LFO spinel as a secondary phase during the synthesis of LixBi1?xFeO3 ceramics. Multimodal functional and chemical imaging methods are used to map the relationship between doping-induced phase separation and local ferroic properties in both the BFO-LFO composite ceramics and self-assembled nanocomposite thin films. The energetics of phase separation in Li doped BFO and the formation of BFO-LFO composites are supported by first principles calculations. These findings shed light on Li’s role in the formation of a functionally important room temperature multiferroic and open a new approach in the synthesis of light element doped nanocomposites for future energy, sensing, and memory applications.
关键词： light element doping,thin film nanostructures,multiferroics,nanoferroic properties,scanning probe microscopy,self-assembled nanocomposites
更新于2025-09-19 17:13:59
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Anti-inflammatory effect of photodynamic therapy using guaiazulene and red lasers on peripheral blood mononuclear cells
摘要： To evaluate the anti-inflammatory effect of photodynamic therapy using guaiazulene and a red laser in peripheral blood mononuclear cells (PBMCs). Guaiazulene solutions (1, 2, 5, 25, 35, and 100 μM in 99.8% methanol) were irradiated with red laser light (625 nm, 151.5 mW/cm2) in continuous mode at 0, 4, and 8 J/cm2 in black 96-well plates. ROS were measured using spin trapping technique with electron spin resonance (ESR) spectroscopy and fluorescence. The two highest concentrations were tested using cell viability (PrestoBlue?) and anti-inflammation (RANTES and PGE2 ELISA) assay kits. Kruskal-Wallis and Dunn Bonferroni tests were used for statistical analyses with significant differences at p-value < 0.05. Guaiazulene solutions between 2 and 5 μM exposed to red laser light at 4-8 J/cm2 generated significantly more singlet oxygen compared to the no guaiazulene group (p < 0.01) and reduced RANTES and PGE2 levels in TNF-α-inflamed peripheral blood mononuclear cells without affecting cell viability. Photodynamic activation of guaiazulene generated singlet oxygen and suppressed inflammatory markers in PBMCs.
关键词： Electron spin resonance spectrometer,RANTES,Fluorescence probe,Singlet oxygen,PGE2,Guaiazulene
更新于2025-09-19 17:13:59
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Ratiometric fluorometric determination of silver(I) by using blue-emitting silicon- and nitrogen-doped carbon quantum dots and red-emitting N-acetyl-L-cysteine-capped CdTe quantum dots
摘要： A ratiometric fluorometric assay for silver(I) is described. The method makes use of a dually emitting quantum dot hybrid, which is composed of (a) blue-fluorescent silicon- and nitrogen-doped carbon quantum dots (CQDs), and (b) of red-emitting CdTe quantum dots (QDs) capped with N-acetyl-L-cysteine. The red-emitting CdTe QDs undergo strong and specific quenching by Ag(I), whereas the blue-emitting N,Si-CQDs are not quenched. The two kinds of QDs are mixed and used as a ratiometric fluorescent probe. A linear relationship is found between the log of intensities [(I608/I441)0/(I608/I441)] and the concentration of Ag(I) in the range from 5.0–1000 nM, and the limit of detection (at S/N = 3) is 1.7 nM. Possible interferents (including 17 general metal ions, 12 anions and fulvic acid) do not interfere with the determination. The assay was successfully used for the determination of Ag(I) in surface water and wastewater samples. The fluorescence quenching mechanism of the ratiometric assay system was also discussed in detailed.
关键词： Fluorescence quenching mechanism,Surface water,Nitrogen-doped carbon dots,Silver ions,Silicon-doped carbon dots,Wastewaters,3-Aminopropyltriethoxysilane functionalized carbon dots,Quenching efficiency,Dual-emission quantum dots hybrid,Fluorescent probe
更新于2025-09-19 17:13:59
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Fluorometric visualization of mucin 1 glycans on cell surfaces based on rolling-mediated cascade amplification and CdTe quantum dots
摘要： A rolling-mediated cascade (RMC) amplification strategy is described for improved visualization of profiling glycans of mucin 1 (MUC 1) on cell surfaces. CdTe quantum dots (QDs) are used as fluorescent labels. The RMC based amplification allows even distinct glycoforms of MUC1 to be visualized on the surface of MCF-7 cell via an amplified F?rster resonance energy transfer (FRET) imaging strategy that works at excitation/emission wavelengths of 345/610 nm. This is achieved by utilizing antibody against MUC1 modified with the fluorescent label 7-amino-4-methylcoumarin-3-acetic acid (AMCA) as the energy donor in FRET. The QDs (used to label surface glycans) act as acceptors. N-Azidoacetylgalactosamine-Acetylated (Ac4GalNAz) as a non-natural azido sugar, can be incorporated into the glycans of the cell surface, which can promote further labeling. The method has the advantage of only requiring a small amount of non-natural sugar to be introduced in metabolic glycan labeling since too much of an artificial sugar will interfere with the physiological functions of cells.
关键词： Cancer marker,Azide polysaccharide,FRET,Glycosylation,Glycoprotein,DNA probe,Quantum dots,Click reaction,Metabolic labeling,Rolling-mediated cascade amplification
更新于2025-09-19 17:13:59
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Topical dual-probe staining using quantum dot-labeled antibodies for identifying tumor biomarkers in fresh specimens
摘要： Purpose Rapid, intra-operative identification of tumor tissue in the margins of excised specimens has become an important focus in the pursuit of reducing re-excision rates, especially for breast conserving surgery. Dual-probe difference specimen imaging (DDSI) is an emerging approach that uses the difference in uptake/clearance kinetics between a pair of fluorescently-labeled stains, one targeted to a biomarker-of-interest and the other an untargeted isotype, to reveal receptor-specific images of the specimen. Previous studies using antibodies labeled with either enhanced Raman particles or organic fluorophores have shown promising tumor vs. normal diagnostic performance. Yet, the unique properties of quantum dot-labeled antibody complexes (QDACs), which provide spectrally-distinct fluorescence emission from a common excitation source, make them ideal candidates for this application. Herein, we evaluate the diagnostic performance of QDAC-based DDSI in excised xenografts. Procedures Excised fresh specimens of normal tissue and human tumor xenografts with elevated expression of HER2 were stained with a HER2-targeted QDAC and an untargeted QDAC isotype. Stained specimens were imaged on a custom hyperspectral imaging system capable of spectrally separating the quantum dot signatures, and images processed using the DDSI approach. The diagnostic performance of this technique under different incubation temperatures and probe concentrations was evaluated using receiver-operator characteristic analysis. Results HER2-targeted QDAC-DDSI was able to distinguish HER2(+) tumors from normal tissue with reasonably high diagnostic performance; however, this performance was sensitive to temperature during the staining procedure. Area under the curve values were 0.61 when staining at room temperature but increased to over 0.81 when staining at 37 ?C. Diagnostic performance was not affected by increasing stain concentration. Conclusions This study is the first to report dual-probe difference imaging of specimens using QDACs and hyperspectral imaging. Our results show promising diagnostic performance under certain conditions, and compel further optimization and evaluation of this intra-operative margin assessment technique.
关键词： tumor biomarkers,hyperspectral imaging,fresh specimens,quantum dot-labeled antibodies,dual-probe difference specimen imaging
更新于2025-09-19 17:13:59