Tunable Single-Photon Emission with Wafer-Scale Plasmonic Array.

Bright, scalable, and deterministic single-photon emission (SPE) is essential for quantum optics, nanophotonics, and optical information systems. Recently, SPE from hexagonal boron nitride (h-BN) has attracted intense interest because it is optically active and stable at room temperature. Here, we demonstrate a tunable quantum emitter array in h-BN at room temperature by integrating a wafer-scale plasmonic array. The transient voltage electrophoretic deposition (EPD) reaction is developed to effectively enhance the filling of single-crystal nanometals in the designed patterns without aggregation, which ensures the fabricated array for tunable performances of these single-photon emitters. An enhancement of ∼500% of the SPE intensity of the h-BN emitter array is observed with a radiative quantum efficiency of up to 20% and a saturated count rate of more than 4.5 × 106 counts/s. These results suggest the integrated h-BN-plasmonic array as a promising platform for scalable and controllable SPE photonics at room temperature.

Comparisons of Left Atrial Functional Parameters with Left Ventricular Diastolic Dysfunction in a Large Taiwanese Population with Normal Left Ventricular Ejection Fraction According to Age.

BACKGROUND: Recent studies have shown that left atrial (LA) volume is a sensitive morphophysiological indicator of the severity of LV dysfunction and may also be a useful index of cardiovascular risk. In this study, we performed comparisons among left atrial (LA) functional parameters for predicting age-related diastolic dysfunction. METHODS: Echocardiography was performed in 2248 healthy participants with a low possibility of heart disease according to the decennium of age, and reference values were established. Progressive diastolic dysfunction paralleled increasing age and could be well identified by traditional and advanced echocardiographic parameters, including mitral inflow pattern, tissue Doppler parameters, and LA volume. RESULTS: Regarding LA functional parameters analyzed based on the decennium of age, left atrial ejection fraction (LAEF) and emptying fraction could not represent aging diastolic dysfunction well, but LA expansion index ((Volmax - Volmin) × 100% / Volmin) could. Volmax indicated maximal LA volume and Volmin indicated minimal LA volume. In assessments of diastolic dysfunction with receiver operating characteristic curve analysis, the best cut-off value of LA expansion index was < 100%, with an area under the curve (AUC) of 0.86, sensitivity of 80%, and specificity of 74%. LAEF < 30% (AUC 0.76, sensitivity 67%, specificity 70%) and LA emptying fraction < 50% (AUC 0.80, sensitivity 72%, specificity 71%) were also useful but performed less well. CONCLUSIONS: Compared with other LA functional parameters, LA expansion index can well represent age-related diastolic dysfunction.

Joint Estimation of DOA and Frequency of Multiple Sources with Orthogonal Coprime Arrays.

A two-stage method is proposed to jointly estimate the direction-of-arrival (DOA) and carrier frequency (CF) of multiple sources, by using two orthogonal coprime arrays (CPAs). The DOAs of CF-known sources are estimated first by applying a spatial smoothing MUSIC algorithm. The contribution of these source signals is then removed from the originally received signal by applying an orthogonal complement projector. Next, a joint-ESPRIT algorithm is applied to estimate the DOAs and CFs of the remaining CF-unknown sources. With two orthogonal CPA(5, 6), the RMSE of DOA and CF of applying the proposed method to 30 sources, 13 of which have unknown CF, is less than 1% at SNR > 5 dB.

Visualizing the effects of antibiotics on the mouse colonic mucus layer.

Objective: Mucus provides a protective barrier separating sensitive epithelial surfaces from the outside world. The mouse colonic mucus is organized as a bacteria-free inner layer and a bacteria-colonized outer layer. Antibiotic treatments are known to disturb gut microbiota, but their effect on the mucosal barrier is rarely discussed. The aim was to evaluate and visualize the impact of antibiotics on the colonic mucus and the microbial community. Materials and Methods: Two sets of experiments were conducted. In the antibiotic experiment, mice orally ingested both streptomycin and bacitracin for 7 days. In the recovery experiment, mice were allowed to recover for 7 days without antibiotics after having received the 7-day antibiotic treatment. Mouse colons were isolated and divided into proximal, middle, and distal parts. Specimens were examined under a transmission electron microscope to identify morphological changes. The gut microbial community was evaluated by analyzing 16S rDNA sequences isolated from the different parts of the mouse colon. Results: The antibiotic-treated mice were physiologically normal. However, a significantly increased inner mucus layer in the proximal and middle colon and a dramatic decrease in bacterial numbers in the outer mucus layers were observed. The 16S rDNA compositions showed a similarity in the dominant taxa among different colon sections. While control mice had a diverse microbiota, antibiotic treatments effectively eliminated most of the bacteria, such that the community was dominated by only one genus (Turicibacter or Staphylococcus). Furthermore, following antibiotic withdrawal in treated mice, the thickness of the inner mucus layer returned to control levels, and the microbial community regained a more complex structure, dominated by Firmicutes, Bacteroidetes, and Proteobacteria. Conclusions: Our results indicated that antibiotic treatments not only disturbed the microbiota but also altered the structure of the mucus layer. After the withdrawal of antibiotics, the mucus layer was quickly regenerated within days, probably in response to microbial growth. The recolonization by gut inhabitants with diverse ecological roles, such as mucin-degraders and fermenters indicate that the gut ecosystem is functionally sound and highly resilient.

Measurement of scapular medial border and inferior angle prominence using a novel scapulometer: A reliability and validity study.

BACKGROUND: Previous studies have proposed various ways to assess scapular dyskinesis. In clinic, assessment tools designed to measure the posterior displacement of the inferior angle of the scapula with reference to the posterior thoracic cage are needed. OBJECTIVES: A novel scapulometer was developed to measure scapular medial border and inferior angle prominence. METHODS: A novel scapulometer was designed to measure the distance from the root of the spine (ROS) and the inferior angle (INF) of the scapula to the thorax wall in 29 participants with scapular dyskinesis bilaterally. Two raters measured the ROS and INF distance of the scapula 3 times bilaterally. Intraclass correlation coefficients (ICC) and standard error of measurement (SEM) were calculated to determine the inter-rater and intra-rater reliability. Validity was based on correlations (convergent: ROS and internal/external rotation, and INF and tilt; divergent: ROS/INF and upward rotation of the scapula) using a FASTRAK Polhemus 3-D motion tracking system assessing scapular tilt, internal/external rotation, and upward/downward rotation. RESULTS: The average ROS and INF displacements were 13.7 ± 5.0 mm and 12.5 ± 6.3 mm, respectively. The results showed excellent intra-rater and inter-rater reliability, with ICC = 0.88-0.99 and 0.95-0.99 (SEM = 0.7-0.8 mm), respectively. Correlations were 0.35/0.19 (convergent validity) and 0.07/0.09 (divergent validity). CONCLUSIONS: The novel scapulometer has excellent reliability and fair validity to quantify medial border and inferior angle prominence of the scapula. Further research utilizing this instrument is recommended.