RESUMEN
Constructing a phosphor with multifunctional applications is an imperative challenge. Especially, highly thermostable luminescence of phosphor is indispensable for stable white-light-emitting diodes (LEDs). Nevertheless, good thermal quenching resistance behavior is unfavorable for a fluorescence intensity ratio (FIR)-based optical temperature sensor. Herein, a highly thermostable Ba3(ZnB5O10)PO4 (BZBP)-based phosphor is successfully achieved via replacing Ba2+ with Dy3+, demonstrating simultaneously promising lighting and thermometry utilizations. Under the excitation of 350 nm, the title phosphor only loses 12% of the initial intensity when the temperature is up to 473 K, ensuring sufficient luminescence thermostability for white-LED lighting. The white-LED device fabricated using the title phosphor emits high-quality white light with a high color rendering index (Ra = 93) and low correlated color temperature (CCT = 3996 K). Meanwhile, the yellow and blue emission intensities demonstrate a downtrend difference with rising temperature. Temperature sensing properties are assessed through FIR technology. The maximal relative sensitivity reaches as high as 0.0379 K-1 at 298 K. These results reveal that the title phosphor has a great potential for indoor lighting and thermometry applications.
RESUMEN
Nine undescribed azaphilone derivatives, sclerazaphilones A-H (1-9), and three known analogues (10-12), were obtained and identified from the fermented rice cultures of a mangrove endophytic fungus Penicillium sclerotiorum ZJHJJ-18. 1D and 2D NMR, HRESIMS and spectral data indicated the chemical structures of 1-9, and their absolute configurations were assigned by experimental and computational analyses of electronic circular dichroism (ECD) spectra, and application of the chemical transformations. Compounds 1-4 were the first reported N-containing azaphilone derivatives with 5/6 dicyclic core. The bioassay results showed that compounds 3-5 exhibited effective inhibitory effects on the nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells with IC50 values in the range of 6.30-9.45 µM. Moreover, a molecular docking study was conducted to investigate the probable binding interaction of 3-5 with inducible nitric oxide synthase (iNOS).
Asunto(s)
Penicillium , Antiinflamatorios/química , Antiinflamatorios/farmacología , Benzopiranos , Hongos , Simulación del Acoplamiento Molecular , Estructura Molecular , Penicillium/química , Pigmentos BiológicosRESUMEN
KEY MESSAGE: High-resolution genome-wide association study (GWAS) facilitated QTL fine mapping and candidate gene identification, and the GWAS based genomic prediction models were highly predictive and valuable in wheat genomic breeding. Wheat is a major staple food crop and provides more than one-fifth of the daily calories and dietary proteins for humans. Genome-wide association study (GWAS) and genomic selection (GS) for wheat stress resistance and tolerance related traits are critical to understanding their genetic architecture for improvement of breeding selection efficiency. However, the insufficient marker density in previous studies limited the utility of GWAS and GS in wheat genomic breeding. Here, we conducted a high-resolution GWAS for wheat leaf rust (LR), yellow rust (YR), powdery mildew (PM), and cold tolerance (CT) by genotyping a panel of 768 wheat cultivars using genotyping-by-sequencing. Among 153 quantitative trait loci (QTLs) identified, 81 QTLs were delimited to ≤ 1.0 Mb intervals with three validated using bi-parental populations. Furthermore, 837 stress resistance-related genes were identified in the QTL regions with 12 showing induced expression by YR and PM pathogens. Genomic prediction using 2608, 4064, 3907, and 2136 pre-selected SNPs based on GWAS and genotypic correlations between the SNPs showed high prediction accuracies of 0.76, 0.73, and 0.78 for resistance to LR, YR, and PM, respectively, and 0.83 for resistance to cold damage. Our study laid a solid foundation for large-scale QTL fine mapping, candidate gene validation and GS in wheat.
Asunto(s)
Cromosomas de las Plantas/genética , Frío , Resistencia a la Enfermedad/inmunología , Genoma de Planta , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/metabolismo , Triticum/genética , Basidiomycota/fisiología , Mapeo Cromosómico/métodos , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Estudio de Asociación del Genoma Completo , Fitomejoramiento , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Triticum/crecimiento & desarrollo , Triticum/microbiologíaRESUMEN
Three new metabolites, furobenzotropolones A, B (1-2) with unusual benzene and dihydrofuran moieties and 3-hydroxyepicoccone B (3), together with seven known compounds (4-10) were obtained from the endophytic fungus Epicoccum nigrum MLY-3 isolated from the fresh leaf of mangrove plant Bruguiear gymnorrhiza collected from Zhuhai. Their structures were assigned by the analysis of UV, IR, NMR, and mass spectroscopic data. Compound 1 was further confirmed by single-crystal X-ray diffraction experiment using Cu Kα radiation. In antioxidant activities in vitro, compounds 2, 3, 5, and 8 showed promising DPPH· scavenging activity with IC50 values ranging from 14.7 to 29.3 µM. Compounds 2, 3, 5, 7, and 8 exhibited promising potent activity in scavenging ABTS· with IC50 values in the range of 18-29.2 µM, which was stronger than that of the positive control ascorbic acid (IC50 = 33.6 ± 0.8 µM).
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Antioxidantes/farmacología , Ascomicetos , Piperazinas/farmacología , Tropolona/farmacología , Animales , Antioxidantes/química , Compuestos de Bifenilo , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Picratos , Piperazinas/química , Hojas de la Planta/microbiología , Tropolona/química , HumedalesRESUMEN
Eleven new ophiobolin-type sesterterpenoids, asperophiobolins A-K (1-11), along with 12 known analogues (12-23) were isolated from the cultures of the mangrove endophytic fungus Aspergillus sp. ZJ-68. The structures of the new compounds were elucidated through spectroscopic analyses, and their absolute configurations were assigned by a combination of Mo2(AcO)4-induced electronic circular dichroism spectra and quantum chemical calculations. Asperophiobolins A-D (1-4) represent the first examples possessing a five-membered lactam unit between C-5 and C-21 in ophiobolin derivatives. In the bioactivity assays, compounds 8-10 and 14-17 exhibited inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophage cells with IC50 values ranging from 9.6 to 25 µM, and compound 8 was found to show comparable inhibition of Mycobacterium tuberculosis protein tyrosine phosphatase B with an IC50 value of 19 µM.
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Aspergillus/química , Rhizophoraceae/microbiología , Sesterterpenos/aislamiento & purificación , Animales , Ratones , Células RAW 264.7 , Sesterterpenos/farmacologíaRESUMEN
Three new benzofuranoids, asperfuranoids A-C (1-3), two new phenylpropanoid derivatives (6 and 7), and nine known analogues (4, 5, and 8-14) were isolated from the liquid substrate fermentation cultures of the mangrove endopytic fungus Aspergillus sp. ZJ-68. The structures of the new compounds were determined by extensive spectroscopic data interpretation. The absolute configurations of 1-3 were assigned via the combination of Mosher's method, and experimental and calculated electronic circular dichroism (ECD) data. Compounds 4 and 5 were a pair of enantiomers and their absolute configurations were established for the first time on the basis of their ECD spectra aided with ECD calculations. All isolated compounds (1-14) were evaluated for their enzyme inhibitory activity against α-glucosidase and antibacterial activities against four pathogenic bacteria (Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Pseudomonas aeruginosa). Among them, compound 6 exhibited potent inhibitory activity against α-glucosidase in a standard in vitro assay, with an IC50 value of 12.4 µM, while compounds 8 and 11 showed activities against S. aureus, E. coli, and B. subtilis, with MIC values in the range of 4.15 to 12.5 µg/mL.
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Aspergillus/química , Propanoles/química , Antibacterianos/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Productos Biológicos/química , Productos Biológicos/farmacología , Pruebas de Sensibilidad Microbiana , Propanoles/farmacologíaRESUMEN
Achieving single-phase full-spectrum white light (SFWL) phosphors is a central goal in the optical field because they simplify white-LEDs assembly and avoid long-term color instability. Despite many approaches are developed, current SFWL phosphors still suffer from chromaticity drift due to inconsistent thermal quenching of multiple emitting centers. Herein, an absolutely structural disorder strategy is established to develop a single-emitting center-based SFWL phosphor. Precisely controlling the flux added induces a structural translation from the absolutely ordered Y0.75Ta0.25O1.75:Bi3+ to the absolutely disordered Y0.785Ta0.215O1.715:Bi3+, as directly identified by STEM-HAADF analyses. Structural disorder enables Y0.785Ta0.215O1.715:Bi3+ to produce SFWL with the FWHM of 6194 cm-1 (175 nm) by employing a single activator site, a 1352 cm-1 increase compared to the cyan-emitting Y0.75Ta0.25O1.75:Bi3+ despite Bi3+ occupies two lattice positions. This single-emitting center-based SFWL, coupled with minimal thermal expansion of the unit cell and inapparent spectral overlap of excitation and emission bands, ensure zero-chromaticity shift with elevated temperature. A prototype white-LEDs using Y0.785Ta0.215O1.715:Bi3+ as a single luminescent layer generates warm white light without perceptible CIE coordinates shift under various currents or after extremely long-term continuous operation. This work highlights the potential of structural disorder in designing SFWL phosphors with exceptional color stability.
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The current ideological and political (IAP) teaching has some disadvantages, such as emphasizing theoretical form over practical teaching, students' differences in personality and cognition, and lack of interaction between teachers and students. Therefore, this paper first analyzes IAP teaching based on VR communication and summarizes the disadvantages of current IAP teaching and the application advantages of VR technology. Based on the principles of interactivity, practicality, and richness, the IAP teaching system is constructed based on the double-center teaching mode, and the teaching content are designed. In addition, in order to provide a carrier for VR IAP teaching, this paper designs the functional module, development process, and framework of the development of VR venues with red theme, combining with red historical events. The IAP education system proposed in this paper can help to explore the potential and advantages of VR technology that applied to IAP education in colleges and realize the modernization of IAP education.
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Estudiantes , Realidad Virtual , Comunicación , Humanos , UniversidadesRESUMEN
We demonstrate Li+-doping engineering for improving the near-infrared (NIR) photoresponse in an Er3+-activated Y2O3 phosphor. We show that the rational incorporation of Li+ results in a large enhancement of the upconversion (UC) emission intensity up to 29 times upon excitation of NIR light. The improved UC properties could be associated with the enhanced dipole-dipole transition probability due to Li+-induced changes in the local site symmetry for Er3+ ions and improvement in the crystallinity of the samples. We further demonstrate the construction of UC phosphor/polymer composite films by attaching the UC phosphor/polymer composite film onto a Si-photoresistor. The device shows a large enhancement of the photovoltage response from 0.16 to 0.4 V in Li-doped samples under NIR light illumination. These results suggest an effective doping strategy for the improvement of the UC performance of the oxide phosphor and its wide applications in solar energy utilization and NIR response devices.
RESUMEN
Wheat (Triticum aestivum) is a major staple food crop worldwide. Genetic dissection of important agronomic traits is essential for continuous improvement of wheat yield to meet the demand of the world's growing population. We conducted a large-scale genome-wide association study (GWAS) using a panel of 768 wheat cultivars that were genotyped with 327 609 single-nucleotide polymorphisms generated by genotyping-by-sequencing and detected 395 quantitative trait loci (QTLs) for 12 traits under 7 environments. Among them, 273 QTLs were delimited to ≤1.0-Mb intervals and 7 of them are either known genes (Rht-D, Vrn-B1, and Vrn-D1) that have been cloned or known QTLs (TaGA2ox8, APO1, TaSus1-7B, and Rht12) that were previously mapped. Eight putative candidate genes were identified for three QTLs that enhance spike seed setting and grain size using gene expression data and were validated in three bi-parental populations. Protein sequence analysis identified 33 putative wheat orthologs that have high identity with rice genes in QTLs affecting similar traits. Large r2 values for additive effects observed among the QTLs for most traits indicated that the phenotypes of these identified QTLs were highly predictable. Results from this study demonstrated that significantly increasing GWAS population size and marker density greatly improves detection and identification of candidate genes underlying a QTL, solidifying the foundation for large-scale QTL fine mapping, candidate gene validation, and developing functional markers for genomics-based breeding in wheat.
Asunto(s)
Estudio de Asociación del Genoma Completo/métodos , Triticum/genética , Cromosomas de las Plantas/genética , Sitios de Carácter Cuantitativo/genéticaRESUMEN
A pair of enantiomeric indole diketopiperazine alkaloid dimers [(-)- and (+)-asperginulin A (1a and 1b)] with an unprecedented 6/5/4/5/6 pentacyclic skeleton were isolated from the mangrove endophytic fungus Aspergillus sp. SK-28. The enantiomeric dimers were separated by chiral-phase HPLC. Their structures including absolute configurations were elucidated by spectroscopic analysis, X-ray diffraction, and quantum chemical calculation. (+)-Asperginulin A (1b) exhibited antifouling activity against the barnacle Balanus reticulatus.