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Developing violet‐light‐excitable deep‐red (650–660 nm) Eu2+‐activated phosphor is essential for full‐spectrum lighting. However, the related phosphors with facile synthesis, excellent optical performance, and superior thermal stability are scarce. Herein, a new class of (Sr,Ba)Lu2O4: Eu2+ deep‐red phosphor (660 nm) excitable by violet light via Ba2+‐induced local structure engineering is reported. Impressively, tunable emission from 615 to 682 nm, accompanied by significant improvement of thermal stability (81%@423 K), is achieved by partially substituting Sr2+ by Ba2+ in SrLu2O4: Eu2+. Crystal field analysis, density functional theory calculations, and thermoluminescence spectra confirm that the strong distortion and enhanced covalency of [EuO6] octahedron are responsible for spectral tunability, and the formation of shallow trapping states is beneficial for electron compensation to inhibit thermal quenching in the Sr0.85Ba0.15Lu2O4: Eu2+ phosphor. Finally, a white light‐emitting diode prototype fabricated by coupling of the Sr0.85Ba0.15Lu2O4: Eu2+ deep‐red phosphor and commercial blue/green phosphors with violet chip can yield sunlight‐like white light with an ultra‐high color rendering index (Ra = 95.2, R9 = 97.0) and an appropriate correlated color temperature of 4121 K, verifying its significant application potential in full‐spectrum solid‐state lighting. [ABSTRACT FROM AUTHOR]

Laser‐driven projection display puts forward urgent demand for color converter materials to achieve wide‐color‐gamut and high‐quality image presentation. In this study, a hierarchical structure quantum dots‐in‐glass film (QiGF) is fabricated via co‐sintering stable green/red‐emitting CsPbX3@glass (X3 = Br3, Br1.5I1.5) and commercial low‐melting glass on the sapphire substrate. Benefiting from the well‐retained optical properties of CsPbX3 quantum dots in amorphous glass and high thermal conductivity, QiGF succeeded in inhibiting luminescence saturation after 20 W mm−2 blue laser irradiation. A brand‐new white‐lighting source designed by coupling a blue laser with a pattern "QiGF wheel" produced ultra‐narrow blue/green/red tri‐color emissions and total luminous flux of 146 lm. Accordingly, a QiGF‐converted laser projection system is successfully designed for the first time, showing more natural and real color restoration for its wide color gamut display feature (157% of conventional light‐emitting diode projection and 107% of NTSC standard). The present study highlights the practical application of CsPbX3 quantum dots composite as an efficient laser‐driven color converter in projection display. [ABSTRACT FROM AUTHOR]

Background and aims: 25‐hydroxyvitamin D (25(OH)D) affects glucose metabolism by increasing insulin secretion and insulin receptor expression. However, whether 25(OH)D deficiency will increase the risk of gestational diabetes mellitus (GDM) has not been clearly reported. The purpose of this study is to assess the relationship between vitamin D levels in the second trimester of pregnancy and the risk of GDM. Methods: According to the inclusion and exclusion criteria, 247 pregnant women came to the fourth hospital of Shijiazhuang (The affiliated obstetrics and gynecology hospital of Hebei Medical University) for obstetrics were investigated during the period of January 1, 2019 to December 31, 2020. The levels of 25(OH)D in the second trimester (16–20 weeks) and oral 75 g glucose tolerance test (OGTT) at 24–28 weeks of pregnancy were reviewed. The sociodemographic data were collected from questionnaire. Multivariate logistic regression was used to analyze the relationship between vitamin D levels and GDM. Results: The incidence of GDM in the observation group (25(OH)D ≤ 26 ng/ml) was higher than that in the control group (25(OH)D > 26 ng/ml) (p = 0.039). Compared with control group, the observation group had significantly higher level of fasting plasma glucose (FPG) (4.7 [4.5–5.0] mmol/L vs. 4.6 [4.4–4.8] mmol/L, p = 0.012). In the whole study, the level of 25(OH)D was negatively correlated with FPG (r = − 0.164，p = 0.010). After adjusting for age, pre‐pregnancy BMI, parity and adverse pregnancy history, compared with the observation group (25 (OH) D ≤ 26 ng/ml), the risk of developing GDM decreased by 50.9% in control group (25(OH)D > 26 ng/ml) (odds ratio [OR] = 0.491, 95% confidence interval [CI] = 0.243–0.989, p = 0.047). Conclusion: Adequate vitamin D levels during the second trimester of pregnancy may reduce the risk of GDM. [ABSTRACT FROM AUTHOR]

Currently, advanced optical security techniques are imminent in response to the increasingly rampant counterfeit and pirated goods on a global scale. Herein, hexagonal Na(NdxY1−x)F4 (x = 0–1) solid‐solution nanocrystals (NCs) embedded glasses are successfully fabricated via in situ glass crystallization. Benefited from the protection of inorganic glass, Na(NdxY1−x)F4 NCs exhibit superior long‐term stability and can endure high‐power 808 nm laser irradiation. Importantly, opposite variations between near‐infrared (NIR) luminescence and laser‐induced temperature can be detected for the nanocomposites, which are sensitive to Nd3+ doping concentration. As a proof‐of‐concept experiment, Nd3+ concentration dependent anti‐counterfeiting patterns with high‐concealment and high‐precision are designed and show bright emission and dimmish thermal images in Nd3+‐tenuous composites under the irradiation of 808 nm laser, while opposite displays can be achieved in Nd3+‐enriched one. This kind of information encryption triggered by a commercial single light source to achieve dual opposing displays in one material can effectively improve security in anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Currently, exploiting luminescent materials with super thermal stability and high luminous efficiency are highly urgent to meet the needs of fast developing high‐power solid‐state lighting (SSL). Glass ceramic (GC) bulk material is an optimal medium with rigid glass network structure and controllable glass crystallization. Herein, an in situ glass crystallization strategy combined with self‐reduced Eu2+ is developed to fabricate Eu2+ doped NaAlSiO4 (NASO) GC composites in air. Structural and spectroscopic characterizations verify that the in situ precipitated NASO nanocrystals with high crystallization density can accommodate Eu2+ emitting centers in the same glass region, which facilitates the separation of Eu2+ dopants from glass into crystalline lattice without the requirement of long‐distance ionic diffusion and provides strong crystal‐field environment for Eu2+ 5d‐4f transition. Particularly, the present composites can produce intense greenish‐yellow emission with apparent photoluminescence quantum yield (PLQY) of ≈70%, intrinsic PLQY of ≈100%, superior thermal stability with 90% PL remained at 150 °C and excellent water‐resistance. Employing NSAO: Eu2+ GC as a color converter, the performance of constructed light‐emitting diode (LED)/laser diode (LD) lighting devices is extraordinary and stable during long‐term working. These findings would expand the application of GC composites and open up new avenues for exploration of novel GC materials and glass crystallization strategies. [ABSTRACT FROM AUTHOR]

Siberian apricot (Prunus sibirica L.), an excellent woody oil plant unique to Asia, is well known for its ability to produce high‐oil seeds for use as a promising feedstock of biodiesel. Based on the investigation of natural Siberian apricot resources in China in the early stage, seeds of Siberian apricot from 74 geographic provenances which can fully reflect the overall information were collected. In this research, seeds oil content, fatty acid composition and biodiesel properties were evaluated, and the key environmental factors that caused the variation of these in different geographic provenance were analyzed. The oil content of Siberian apricot seeds is 45.48%–61.07%, and the average was 50.95% for all provenances. The characteristics of oil can identify and quantify eight fatty acids. The most abundant fatty acids were oleic acid (C18:1; 54.02%–76.54%), followed by linoleic acid (C18:2; 16.78%–38.49%) and erucic acid (C16:0; from 3.27% to 6.12%). Monounsaturated fatty acids are the most abundant in 54.75%–77.03% compared with saturated fatty acids and polyunsaturated fatty acids. The biodiesel properties of most provenance seeds meet the standards of the ASTM D6751 and GB/T 20828, and a few meet the standards of the EN14214. Through the clustering of oil content and fatty acid composition and the analysis of biodiesel properties indexes, it is concluded that KSK provenance is the most suitable for biodiesel production. The XBZ, HHE, AES, ZLQ and LD provenances may be preserved as potential biodiesel. RDA and VPA showed that the effects of environmental factors on the oil properties of Siberian apricot were ranked as terrain factor > climate factor > soil factor, among which longitude, latitude and altitude are the main terrain indicators. These evaluations can provide reference for the effective utilization and further development of Siberian apricot as a bioenergy feedstock. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) nanomaterials show unique electrical, mechanical, and catalytic performance owing to their ultrahigh surface-to-volume ratio and quantum confinement effects. However, ways to simply synthesize 2D metal oxide nanosheets through a general and facile method is still a big challenge. Herein, we report a generalized and facile strategy to synthesize large-size ultrathin 2D metal oxide nanosheets by using graphene oxide (GO) as a template in a wet-chemical system. Notably, the novel strategy mainly relies on accurately controlling the balance between heterogeneous growth and nucleation of metal oxides on the surface of GO, which is independent on the individual character of the metal elements. Therefore, ultrathin nanosheets of various metal oxides, including those from both main-group and transition elements, can be synthesized with large size. The ultrathin 2D metal oxide nanosheets also show controllable thickness and unique surface chemical state. [ABSTRACT FROM AUTHOR]

Background Dopamine D 5 receptor (D 5 R) plays an important role in the maintenance of blood pressure by regulating renal sodium transport. Our previous study found that human D 5 R mutant F173L transgenic ( hD 5 R F173L -TG) mice are hypertensive. In the present study, we aimed to investigate the mechanisms causing this renal D 5 R dysfunction in hD 5 R F173L -TG mice. Methods and Results Compared with wild-type D 5 R-TG ( hD 5 R WT -TG) mice, hD 5 R F173L -TG mice have higher blood pressure, lower basal urine flow and sodium excretion, and impaired agonist-mediated natriuresis and diuresis. Enhanced reactive oxygen species production in hD 5 R F173L -TG mice is caused, in part, by decreased expression of antioxidant enzymes, including thioredoxin 1 (Trx1). Na + -K + -ATPase activity is increased in mouse renal proximal tubule cells transfected with hD 5 R F173L , but is normalized by treatment with exogenous recombinant human Trx1 protein. Regulation of Trx1 by D 5 R occurs by the phospholipase C/ protein kinase C (PKC) pathway because upregulation of Trx1 expression by D 5 R does not occur in renal proximal tubule cells from D 1 R knockout mice in the presence of a phospholipase C or PKC inhibitor. Fenoldopam, a D 1 R and D 5 R agonist, stimulates PKC activity in primary renal proximal tubule cells of hD5R WT -TG mice, but not in those of hD 5 R F173L -TG mice. Hyperphosphorylation of hD 5 R F173L and its dissociation from Gαs and Gαq are associated with impairment of D 5 R-mediated inhibition of Na + -K + -ATPase activity in hD 5 R F173L -TG mice. Conclusions These suggest that hD 5 R F173L increases blood pressure, in part, by decreasing renal Trx1 expression and increasing reactive oxygen species production. Hyperphosphorylation of hD 5 R F173L , with its dissociation from Gαs and Gαq, is the key factor in impaired D 5 R function of hD 5 R F173L -TG mice.