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All-inorganic CsPbX3 (X = Cl, Br, I) perovskite quantum dots (QDs) are prone to degradation under certain conditions, such as air, ultraviolet light and high temperature, which limits their practical applications. Here, we report the utilization of four kinds of BN nanomaterials, namely BN nanosheets (BNNS), BN nanofibers (BNNF), commercial BN nanosheets (C-BNNS) and BN nanospheres (BNNP), as carriers for supporting CsPbBr3 (CPB) QDs to obtain a series of CPB/BN nanocomposites. A comprehensive study on the microstructures, photoluminescence (PL) properties, and the stabilities of various nanocomposites under different conditions (air, ultraviolet light and high temperature) has been carried out. The results show that the addition of BN can not only retain the excellent PL properties of CsPbBr3 QDs, but also improve their photostabilities, long-term storage stabilities, and thermal stabilities. Comparative studies also demonstrate that BN nanomaterials with different structures have great influence on the properties of CPB/BN nanocomposites. BNNS and BNNF with high specific surface areas and surface functional groups can provide a large number of adsorption sites for the uniform anchoring of CsPbBr3 QDs, thus effectively improving the PL and stability performance of the nanocomposites. In particular, compared with the QDs loaded on the surface of nanofibers, the CsPbBr3 QDs can be better protected by multi-layered nanosheets with a flexible feature and folds, thereby showing higher crystallinity. Finally, the best-performing CPB/BNNS nanocomposite is made into a white LED device, which emits bright white light with a correlated color temperature of 5531 K. The findings can provide an effective guiding strategy for the development of high-performance BN-based nanocomposites, which are of great significance due to their great potential applications in solid-state lighting. [ABSTRACT FROM AUTHOR]

In South-East Asia, cocoa production is dramatically affected by cocoa pod borer (CPB) infestations. As an alternative tool to chemical control, the efficacy of attract-and-kill strategy (CPB sex-pheromone as attractant and Delta trap without sticky liner sprayed with cypermethrin solution as killing station) was evaluated and compared with current standard CPB management approach as control treatment during two main cocoa harvest seasons in Malaysia (with 100 µg and 33.3 µg CPB-pheromone loading per station, respectively). In both seasons, attract-and-kill strategy was highly effective at reducing male flight activity (p < 0.05) in attract-and-kill plots comparing with standard CPB management plots. For the percentage of CPB-infested pods, the attract-and-kill strategy (100 µg) was as good as the conventional pesticide spray applications of cypermethrin (p = 0.083) in first season. However, it was significantly (p = 0.021) reduced in the second season with lower pheromone loading (33.3 µg), indicating that this semiochemical based strategy is far superior to and more feasible than the currently applied conventional synthetic pesticide treatment and is therefore a good alternative in CPB integrated pest management. [ABSTRACT FROM AUTHOR]

Objectives: The present study aimed to compare the diagnostic performance of a machine learning (ML)-based FFRCT algorithm, quantified subtended myocardial volume, and high-risk plaque features for predicting if a coronary stenosis is hemodynamically significant, with reference to FFRICA.Methods: Patients who underwent both CCTA and FFRICA measurement within 2 weeks were retrospectively included. ML-based FFRCT, volume of subtended myocardium (Vsub), percentage of subtended myocardium volume versus total myocardium volume (Vratio), high-risk plaque features, minimal lumen diameter (MLD), and minimal lumen area (MLA) along with other parameters were recorded. Lesions with FFRICA ≤ 0.8 were considered to be functionally significant.Results: One hundred eighty patients with 208 lesions were included. The lesion length (LL), diameter stenosis, area stenosis, plaque burden, Vsub, Vratio, Vratio/MLD, Vratio/MLA, and LL/MLD4 were all significantly longer or larger in the group of FFRICA ≤ 0.8 while smaller minimal lumen area, MLD, and FFRCT value were noted. The AUC of FFRCT + Vratio/MLD was significantly better than that of FFRCT alone (0.935 versus 0.873, p < 0.001). High-risk plaque features failed to show difference between functionally significant and insignificant groups. Vratio/MLD-complemented ML-based FFRCT for "gray zone" lesions with FFRCT value ranged from 0.7 to 0.8 and the combined use of these two parameters yielded the best diagnostic performance (86.5%, 180/208).Conclusions: ML-based FFRCT simulation and Vratio/MLD both provide incremental value over CCTA-derived diameter stenosis and high-risk plaque features for predicting hemodynamically significant lesions. Vratio/MLD is more accurate than ML-based FFRCT for lesions with simulated FFRCT value from 0.7 to 0.8.Key Points: • Machine learning-based FFR CT and subtended myocardium volume both performed well for predicting hemodynamically significant coronary stenosis. • Subtended myocardium volume was more accurate than machine learning-based FFR CT for "gray zone" lesions with simulated FFR value from 0.7 to 0.8. • CT-derived high-risk plaque features failed to correctly identify hemodynamically significant stenosis. [ABSTRACT FROM AUTHOR]

Amino acids are required for the activation of mammalian target of rapamycin (mTOR) to increase cell growth, protein and lipid synthesis, and inhibit autophagy. However, the mechanism through which amino acids activate the mTOR signaling is still largely unknown. In our previous study, we discovered that glycyl‐tRNA synthetase (GlyRS) is a key mediator of amino‐acid‐induced mTOR expression and activation in bovine mammary epithelial cells (BMECs). Here we show that amino acids stimulate GlyRS nuclear localization for mTOR expression in BMECs. Met stimulates GlyRS nuclear localization, and the nuclear GlyRS is cleaved into a C‐terminus‐containing truncated form. We prove that GlyRS has a bipartite nuclear leading sequences, and GlyRS is phosphorylated at Thr544 and Ser704 in the cytoplasm under the stimulation of amino acids (Met, Leu, and Lys). The nuclear GlyRS physically binds to nuclear factor kappa B1, triggers its phosphorylation, thereby enhancing mRNA expression of its target genes including mTOR, S6K1, and 4EBP1. We further demonstrate that GlyRS is required for the inhibition of autophagy by Met. Thus our work elucidates that amino acids trigger GlyRS phosphorylation and nuclear localization to enhance the mRNA expression of mTOR. Glycyl‐tRNA synthetase (GlyRS) has a bipartite type of nuclear localization signals in its WHEP domain, and amino acids (Met, Leu, and Lys) trigger GlyRS phosphorylation at Thr544 and Ser704 in the cytoplasm and subsequent nuclear translocation. Nuclear p‐GlyRS physically interacts with and stimulates nuclear factor kappa B1 phosphorylation, thereby stimulating the expression of its downstream gene mammalian target of rapamycin and inhibiting autophagy. [ABSTRACT FROM AUTHOR]

Previous studies have implicated that purine‐rich element binding protein B (PURB) is a key regulator of gene transcription and cell physiology. Whether PURB plays a regulatory role in milk synthesis in bovine mammary epithelial cells (BMECs) is not known. We observed that Met and Leu increased PURB expression and nuclear localization. Overexpression of PURB led to increased milk protein and fat synthesis as well as mTOR and SREBP‐1c expression whereas PURB knockdown had the opposite effects. The PI3K inhibitor wortmannin totally abolished the stimulation of Met and Leu on PURB expression, and we further confirmed that PURB was required for Met and Leu to stimulate mTOR phosphorylation and SREBP‐1c expression. We also demonstrated that PURB binds to the promoters of mTOR and SREBP‐1c, and these bindings were increased by Met and Leu stimulation. In summary, our data reveal that PURB is required for amino acids to stimulate mTOR and SREBP‐1c gene expression, and PURB is a positive regulator of amino acid‐induced PI3K‐regulated milk protein and fat synthesis in BMECs. Amino acids (Met and Leu) trigger PURB expression in the nucleus via the PI3K signaling and binding to the promoters of mTOR and SREBP‐1c, and PURB is required for amino acids to stimulate the gene expression of mTOR and SREBP‐1c leading to milk protein and fat synthesis in bovine mammary epithelial cells. [ABSTRACT FROM AUTHOR]

The intracellular fatty acid‐binding proteins (FABPs) are a well‐conserved family that function as lipid chaperones. Ongoing studies are focused on identification of the mechanistic complexity and vast biological diversity of different isoforms of FABPs. However, the molecular mechanism of FABP5 in the regulation of milk fat synthesis in the mammary gland of dairy cows is still largely unknown. Here, we report that FABP5 acts as a critical regulator of terol response element‐binding protein‐1c (SREBP‐1c) gene expression induced by methionine (Met) and estrogen (E2) in bovine mammary epithelial cells (BMECs). We observed that the expression of FABP5 was markedly higher in dairy cow mammary tissue during the lactating period than the puberty period and the dry period. FABP5 is located in the cytoplasm, and Met and E2 significantly increase the protein levels of FABP5 in BMECs. Using gene function study approaches, we revealed that FABP5 positively regulates SREBP‐1c gene expression and promotes milk fat synthesis. We confirmed that FABP5 is required for Met‐ and E2‐induced SREBP‐1c gene expression and milk fat synthesis. We further uncovered that fatty acids are needed for FABP5‐mediated SREBP‐1c gene expression. Thus, our study demonstrates that FABP5 is a critical regulator of Met‐ and E2‐induced SREBP‐1c gene expression leading to milk fat synthesis. Fatty acid‐binding proteins 5 (FABP5) is a critical regulator of methionine (Met)‐ and estrogen (E2)‐induced terol response element‐binding protein‐1c (SREBP‐1c) gene expression leading to milk fat synthesis in bovine mammary epithelial cells. Fatty acids are needed for FABP5‐mediated SREBP‐1c gene expression. [ABSTRACT FROM AUTHOR]

Aims To investigate the quantitative baseline CT plaque characterization of unrevascularized non-culprit intermediate coronary stenosis and its association with lesion volume progression and long-term prognosis. Methods Patients with baseline coronary CT angiography (CCTA) and invasive coronary angiography (ICA) and at least one unrevascularized non-culprit intermediate coronary stenosis were prospectively enrolled for this study. All patients were followed up by a second CCTA at 1-year to 1.5-year interval. High-risk plaque features as well as other quantitative plaque measurements were recorded. Results 140 patients with 165 unrevascularized non-culprit intermediate lesions were selected. Lesion volume progression was identified in 18 lesions (10.9%, 18/165) at follow-up CCTA and 15 patients experienced major adverse cardiac events (MACE) during a mean follow-up period of 51.5 months. Low attenuation plaque (LAP) was more frequently present in the lesion-progression subgroup and MACE subgroup (lesion-progression VS. non-lesion progression: 55.6% VS. 8.8% and MACE VS. MACE free: 40% VS. 12.8%, both p  < 0.05), while other parameters showed no significant differences. Based on stepwise multivariable logistic regression analysis, LAP was an independent predictor (OR = 16.74, 95%CI = 5.02 to 55.84, p  < 0.001) for lesion volume progression and MACE (OR = 4.25, 95%CI = 1.03 to 17.53, p  = 0.046). Conclusions The presence of LAP of unrevascularized non-culprit intermediate stenosis is associated with lesion volume progression and an independent predictor for MACE occurrence. [ABSTRACT FROM AUTHOR]

Objectives: To assess pre-procedural plaque characteristics as determined by coronary CT angiography (CCTA) and their associations with late revascularization in symptomatic post-procedural patients.Methods: Symptomatic patients with pre-procedural CCTA were prospectively enrolled and referred for invasive coronary angiography (ICA). Plaque characterization was performed on the basis of baseline CCTA data. Multivariate logistic regression analysis with a stepwise selection method was performed to identify independent predictors of late revascularization.Results: Seventy-eight patients with 134 lesions were included. Late revascularization was performed to treat 15 ISRs and 22 de novo lesions. Lesions with late revascularization showed higher prevalence rates of low-attenuation plaque (LAP) and positive remodelling (PR) (70.3% vs. 23.7% and 86.5% vs. 30.9%; both p < 0.001) at baseline CCTA. However, the incidence of spotty calcification or napkin-ring sign (NRS) was not significantly different between the subgroups. According to ROC curve analysis, PR and LAP showed the largest AUC values for diagnosing lesions with late revascularization (AUC = 0.78 and 0.73, both p < 0.001). In multivariate analysis, LAP and PR (odds ratio = 6.30 and 13.94; both p < 0.05) were revealed to be independent predictors for late revascularization.Conclusions: LAP and PR observed by baseline CCTA independently predict late revascularization caused by ISR or progression of de novo lesions.Key Points: • LAP and PR observed by baseline CT are predictors of late revascularization. • NRS and spotty calcification are not associated with late revascularization. • CT plaque characterization is useful in identifying lesions at high risk of late revascularization. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the diagnostic performance of low dose stent imaging in patients with large (≥ 3 mm) and small (< 3 mm) calibre stents by third-generation dual-source CT.Methods: Symptomatic patients suspected of having in-stent restenosis (ISR) were prospectively enrolled. Coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) were performed within 1 month for correlation. Binary ISR was defined as an in-stent neointimal proliferation with diameter stenosis ≥ 50%. The radiation dose and image quality of CCTA were also assessed.Results: Sixty-nine patients with 140 stents were ultimately included for analysis. The mean total radiation dose of CCTA was 1.3 ± 0.72 mSv in all patients and 0.95 ± 0.17 mSv in patients with high pitch acquisition. The overall diagnostic accuracy of CCTA stent imaging of patient-based, lesion-based and stent-based analysis was 95.7%, 94.1% and 94.3%, respectively. Further, the diagnostic accuracy of CCTA in the small calibre stent group (diameter < 3 mm) was slightly lower than that of the large calibre stent group (diameter ≥ 3 mm) (88.5% versus 98.7%, p = 0.01).Conclusions: Third-generation dual-source CT enables accurate diagnosis of coronary ISR of both large and small calibre stents. Low radiation dose could be achieved with preserved image quality.Key Points: • Third-generation DSCT enables accurate diagnosis of coronary ISR of all size stents. • Low radiation dose could be achieved with preserved image quality. • The diagnostic accuracy of CCTA of small calibre stents was 88.5%. [ABSTRACT FROM AUTHOR]

Objectives To study the diagnostic performance of the ratio between the Duke jeopardy score (DJS) and the minimal lumen diameter (MLD) (DJS/MLD CT ratio) as assessed by coronary computed tomographic angiography (CTA) for differentiating functionally significant from non-significant coronary artery stenoses, with reference to invasive fractional flow reserve (FFR). Methods Patients who underwent both coronary CTA and FFR measurement during invasive coronary angiography (ICA) within 2 weeks were retrospectively included in the study. Invasive FFR measurement was performed in patients with intermediate to severe coronary stenoseis. DJS/MLD CT ratio and anatomical parameters were recorded. Lesions with FFR ≤0.80 were considered to be functionally significant. Results One hundred and sixty-one patients with 175 lesions were included into the analysis. Diameter stenosis in CT, area stenosis, plaque burden, lesion length (LL), ICA-based stenosis degree, DJS, LL/MLD 4 ratio, DJS/MLA ratio as well as DJS/MLD ratio were all significantly different between hemodynamically significant and non-significant lesions (p<0.05 for all). ROC curve analysis determined the optimal cut-off value for DJS/MLD CT ratio to be 1.96 (area under curve = 0.863, 95 % confidence interval = 0.803–0.910), yielding a high diagnostic accuracy (86.9%, 152/175). Conclusions In coronary artery stenoses detected by coronary CTA, the DJS/MLD ratio is able to predict hemodynamic relevance. [ABSTRACT FROM AUTHOR]

Objectives To assess the diagnostic performance of the calcification remodeling index (RI) as assessed by coronary computed tomography angiography (coronary CTA) to predict the presence of severe coronary stenosis in atherosclerotic coronary lesions with moderate to severe calcification. Methods Patients who underwent coronary CTA and invasive coronary angiography (ICA) within one month and had moderately to severely calcified lesions as revealed by coronary CTA, were retrospectively included. The calcification RI was calculated as the ratio of the cross-sectional lumen area (with inclusion of calcium area) of the most severely calcified site to the proximal reference lumen area. Other parameters, such as the calcium volume, regional Agatston score, calcification length, involved calcium arc quadrants and CTA-assessed diameter stenosis, were also recorded. A multivariate model was used to identify the variables that predict the presence of severe coronary stenosis (diameter stenosis ≧ 70%) as determined by ICA. Results 422 patients with 629 lesions were finally included in the study. Lesions with severe stenoses as determined by ICA tended to have larger calcium volumes, regional Agatston scores, CTA-assessed diameter stenoses, longer calcium length, more involved calcium arc quadrants and a significantly smaller calcification remodeling index. ROC curve analysis determined the best cutoff value of the calcification RI as 0.94 (AUC = 0.816, p < 0.001), which yielded highest diagnostic accuracy (83.3%, 524/629) to identify severe coronary stenosis. Among all parameters, calcification RI ≦0.94 is the strongest independent predictor (odds ratio: 17.5, p < 0.001) of severe coronary stenosis. Conclusions With an optimalcut-off value of 0.94, calcification RI is the strongest independent predictor of severe coronary stenosis in calcified coronary atherosclerotic lesions. [ABSTRACT FROM AUTHOR]