Commendable Eu²⁺-Doped Oxide-Matrix-Based LiBa₁₂(BO₃)₇F₄ Red Broad Emission Phosphor Excited by NUV Light: Electronic and Crystal Structures, Luminescence Properties

In this work, we synthesized a new Eu²⁺-doped oxide-matrix-based LiBa₁₂(BO₃)₇F₄ broad red emission phosphor. It can emit red light peaking at ∼644 nm under NUV excitation with the coordinate at (0.6350, 0.3586) and a sensitive color gamut for eyes. This phosphor with a special kind of tunnel crystal structure and layered distribution of Ba²⁺ is contributed to longer wavelength emission. By theoretical calculation and analysis using local state density energy band structure simulation of Eu²⁺ doped in different site, the origin of the observed emission center was distinguished. Furthermore, decay curves analysis also indicated there are three possible Ba²⁺ sites for Eu²⁺ to occupy. Temperature-dependent PL spectra appeared anomalous phenomena that the intensity increases first and then decreases, which is due to the traps energy level’s contribution of electron’s transition. The phosphor also has cathodoluminescence (CL) property which the spectra take on typical current saturation phenomenon. The CL curves indicated that this phosphor has a very good stability under much electron beam bombardment time. After fabricated combining with BAM, (Sr, Ba)₂SiO₄ and our red phosphor excited under 405-nm NUV chips, warm light LED was obtained. Its CIE coordinate is (0.3475, 0.3416) and the CCT, Ra, and luminous efficiency are 4856 K, 84.1, and 72.6 lm/W, respectively

Synthesis, Crystal Structure, and Luminescence Properties of Tunable Red-Emitting Nitride Solid Solutions (Ca_1–<i>x</i>Sr_<i>x</i>)₁₆Si₁₇N₃₄:Eu²⁺ for White LEDs

A series of nitride solid solutions (Ca_1–<i>x</i>Sr_<i>x</i>)₁₆Si₁₇N₃₄:0.03Eu²⁺ were successfully synthesized through the conventional solid-state method. The electronic crystal structure and photoluminescence characteristics were studied in detail. The excitation in the near-ultraviolet and blue regions of the samples shows a broad band in the 250–550 nm range, which can match well with the n-UV and blue lighting-emitting diode chips. Partial substitution of Ca²⁺ by Sr²⁺ results in a redshift emission, and the impacts of Sr content on the luminescence were researched in detail. Under 410 nm excitation, the phosphor exhibited tunable red emission from 616 to 653 nm by changing the concentration of Sr²⁺. Based on the crystal data, the emission can be fitted into three distinguished Gaussian components, which are attributed to the different Eu²⁺ luminescence centers occupied in three disparate Ca²⁺ (Sr²⁺) lattice sites. The temperature quenching property of the phosphor was also investigated, and the good thermal stability of the phosphors was analyzed through the activation energy for thermal quenching. And the obtained CCT values from 2642 to 2817 K are suitable for a warm white light region. All the results indicated that the phosphors have possible application in the warm white light-emitting diodes

Additional file 1: Figures S1–S5. of miR-17-92 facilitates neuronal differentiation of transplanted neural stem/precursor cells under neuroinflammatory conditions

Figure S1. Characterization of the NSCs. Figure S2. Effect of LIF and CNTF on differentiation of NSCs. Figure S3. miR-17-92 members directly target the 3′UTR of CNTFR or GP130. Figure S4. Bioinformatics analysis of miR-17-92 cluster members binding sites within CNTFR, GP130, JAK2, and STAT3. Figure S5. Traumatic brain injury. (PDF 558 kb

Design, Synthesis, and Biological Evaluation of Novel Derivatives of the Marine Natural Product Laurene

Plant pathogenic fungi and viruses are seriously threatening agricultural production. There is an urgent need to develop novel fungicides and antiviral agents with low toxicity and high efficiency. In this study, we designed and synthesized 32 thiazole-, hydrazone-, and amide-containing derivatives of laurene and systematically evaluated their antiviral activities and fungicidal activities. Structure-simplified compounds 5a–5c, 5i, 5k, 5l, 11a, 11j, and 12c displayed higher antiviral activities than that of ningnanmycin. Compound 11a with a simple chemical structure, convenient synthetic route, and excellent antiviral activity emerged as a secondary lead compound. The docking results show that compounds 5i, 5k, and 11a have strong interactions with the tobacco mosaic virus coat protein (TMV CP). These compounds also exhibited significant fungicidal activities. Compounds 5g, 5k, 11j, and 11l displayed 9.15–17.45 μg/mL EC50 values against Pyricularia grisea, and compounds 5h (EC50: 8.01 μg/mL) and 11i (EC50: 15.23 μg/mL) exhibited a similar level of EC50 values with chlorothalonil (EC50: 7.33 μg/mL) against Physalospora piricola. Preliminary fungicidal mechanism research indicated that compound 5h has a certain destructive effect on the hyphae of P. piricola. This work lays a foundation for the application of laurene derivatives in plant protection

Visible Light-Driven Water Splitting in Photoelectrochemical Cells with Supramolecular Catalysts on Photoanodes

By using a supramolecular self-assembly method, a functional water splitting device based on a photoactive anode TiO₂(<b>1</b>+<b>2</b>) has been successfully assembled with a molecular photosensitizer <b>1</b> and a molecular catalyst <b>2</b> connected by coordination of <b>1</b> and <b>2</b> with Zr⁴⁺ ions on the surface of nanostructured TiO₂. On the basis of this photoanode in a three-electrode photoelectrochemical cell, a maximal incident photon to current conversion efficiency of 4.1% at ∼450 nm and a photocurrent density of ∼0.48 mA cm^–2 were successfully obtaine

Visible Light Driven Water Splitting in a Molecular Device with Unprecedentedly High Photocurrent Density

A molecular water oxidation catalyst (<b>2</b>) has been synthesized and immobilized together with a molecular photosensitizer (<b>1</b>) on nanostructured TiO₂ particles on FTO conducting glass, forming a photoactive anode (TiO₂(<b>1</b>+<b>2</b>)). By using the TiO₂(<b>1</b>+<b>2</b>) as working electrode in a three-electrode photoelectrochemical cell (PEC), visible light driven water splitting has been successfully demonstrated in a phosphate buffer solution (pH 6.8), with oxygen and hydrogen bubbles evolved respectively from the working electrode and counter electrode. By applying 0.2 V external bias vs NHE, a high photocurrent density of more than 1.7 mA·cm^–2 has been achieved. This value is higher than any PEC devices with molecular components reported in literature

Visible Light Driven Water Splitting in a Molecular Device with Unprecedentedly High Photocurrent Density

A molecular water oxidation catalyst (<b>2</b>) has been synthesized and immobilized together with a molecular photosensitizer (<b>1</b>) on nanostructured TiO₂ particles on FTO conducting glass, forming a photoactive anode (TiO₂(<b>1</b>+<b>2</b>)). By using the TiO₂(<b>1</b>+<b>2</b>) as working electrode in a three-electrode photoelectrochemical cell (PEC), visible light driven water splitting has been successfully demonstrated in a phosphate buffer solution (pH 6.8), with oxygen and hydrogen bubbles evolved respectively from the working electrode and counter electrode. By applying 0.2 V external bias vs NHE, a high photocurrent density of more than 1.7 mA·cm^–2 has been achieved. This value is higher than any PEC devices with molecular components reported in literature

Broad-Spectrum Antimicrobial/Antifouling Soft Material Coatings Using Poly(ethylenimine) as a Tailorable Scaffold

Microbial colonization and biofilm formation is the leading cause of contact lens-related keratitis. Treatment of the condition remains a challenge because of the need for prolonged therapeutic course and high doses of antimicrobial agents especially for biofilm eradication. The development of strategies to prepare nonfouling contact lens surfaces is a more practical way to ensure users’ safety and relieve the excessive public healthcare burden. In this study, we report a series of polymers that were modified to introduce functionality designed to facilitate coating adhesion, antimicrobial and antifouling properties. Cyclic carbonate monomers having different functional groups including adhesive catechol, antifouling poly­(ethylene glycol) (PEG), and hydrophobic urea/ethyl were conjugated onto branched poly­(ethylenimine) (bPEI, 25 kDa) at various degrees in a facile and well-controlled manner using a simple one step, atom economical approach. Immersion of contact lenses into an aqueous solution of the catechol-functionalized polymers at room temperature resulted in robust and stable coating on the lens surfaces, which survived the harsh condition of autoclaving and remained on the surface for a typical device application lifetime (7 days). The deposition of the polymer was unambiguously confirmed by static contact angle measurement and X-ray photoelectron spectroscopy (XPS). Polymer coating did not change light transmission significantly. Combinatorial optimization demonstrated that lenses coated with bPEI functionalized with catechol, PEG (5 kDa) and urea groups at 1:12:3:23 molar ratio for 18 h provided the highest antifouling effect against four types of keratitis-causing pathogens: Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Fusarium solani, after 7 days of incubation. The polymer coating also inhibited protein adsorption onto the contact lens surfaces after exposure to bovine serum albumin solution for up to 24 h, owing to the flexible and large PEG constituent. Notably, all the polymer coatings used in this study were biocompatible, achieving ≥90% cell viability following direct contact with human corneal epithelial cells for 24 h. Hence, these polymer coatings are envisaged to be promising for the prevention of contact lens-related keratitis

Enhancing Electrochemical Performance of Graphene Fiber-Based Supercapacitors by Plasma Treatment

Graphene fiber-based supercapacitors (GFSCs) hold high power density, fast charge–discharge rate, ultralong cycling life, exceptional mechanical/electrical properties, and safe operation conditions, making them very promising to power small wearable electronics. However, the electrochemical performance is still limited by the severe stacking of graphene sheets, hydrophobicity of graphene fibers, and complex preparation process. In this work, we develop a facile but robust strategy to easily enhance electrochemical properties of all-solid-state GFSCs by simple plasma treatment. We find that 1 min plasma treatment under an ambient condition results in 33.1% enhancement of areal specific capacitance (36.25 mF/cm²) in comparison to the as-prepared GFSC. The energy density reaches 0.80 μW h/cm² in polyvinyl alcohol/H₂SO₄ gel electrolyte and 18.12 μW h/cm² in poly­(vinylidene difluoride)/ethyl-3-methylimidazolium tetrafluoroborate electrolyte, which are 22 times of that of as-prepared ones. The plasma-treated GFSCs also exhibit ultrahigh rate capability (69.13% for 40 s plasma-treated ones) and superior cycle stability (96.14% capacitance retention after 20 000 cycles for 1 min plasma-treated ones). This plasma strategy can be extended to mass-manufacture high-performance carbonaceous fiber-based supercapacitors, such as graphene and carbon nanotube-based ones

Caloric restriction reduces the systemic progression of mouse AApoAII amyloidosis

<div><p>In mouse senile amyloidosis, apolipoprotein (Apo) A-II is deposited extracellularly in many organs in the form of amyloid fibrils (AApoAII). Reduction of caloric intake, known as caloric restriction (CR), slows the progress of senescence and age-related disorders in mice. In this study, we intravenously injected 1 μg of isolated AApoAII fibrils into R1.P1-<i>Apoa2c</i> mice to induce experimental amyloidosis and investigated the effects of CR for the next 16 weeks. In the CR group, AApoAII amyloid deposits in the liver, tongue, small intestine and skin were significantly reduced compared to those of the <i>ad libitum</i> feeding group. CR treatment led to obvious reduction in body weight, improvement in glucose metabolism and reduction in the plasma concentration of ApoA-II. Our molecular biological analyses of the liver suggested that CR treatment might improve the symptoms of inflammation, the unfolded protein response induced by amyloid deposits and oxidative stress. Furthermore, we suggest that CR treatment might improve mitochondrial functions via the sirtuin 1-peroxisome proliferator-activated receptor γ coactivator 1α (SIRT1-PGC-1α) pathway. We suggest that CR is a promising approach for treating the onset and/or progression of amyloidosis, especially for systemic amyloidosis such as senile AApoAII amyloidosis. Our analysis of CR treatment for amyloidosis should provide useful information for determining the cause of amyloidosis and developing effective preventive treatments.</p></div