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Allergic asthma is characterized by goblet cell metaplasia and subsequent mucus hypersecretion that contribute to the morbidity and mortality of this disease. Here, we explore the potential role and underlying mechanism of protein SUMOylation-mediated goblet cell metaplasia. The components of SUMOylaion machinery are specifically expressed in healthy human bronchial epithelia and robustly upregulated in bronchial epithelia of patients or mouse models with allergic asthma. Intratracheal suppression of SUMOylation by 2-D08 robustly attenuates not only allergen-induced airway inflammation, goblet cell metaplasia, and hyperreactivity, but IL-13-induced goblet cell metaplasia. Phosphoproteomics and biochemical analyses reveal SUMOylation on K1007 activates ROCK2, a master regulator of goblet cell metaplasia, by facilitating its binding to and activation by RhoA, and an E3 ligase PIAS1 is responsible for SUMOylation on K1007. As a result, knockdown of PIAS1 in bronchial epithelia inactivates ROCK2 to attenuate IL-13-induced goblet cell metaplasia, and bronchial epithelial knock-in of ROCK2(K1007R) consistently inactivates ROCK2 to alleviate not only allergen-induced airway inflammation, goblet cell metaplasia, and hyperreactivity, but IL-13-induced goblet cell metaplasia. Together, SUMOylation-mediated ROCK2 activation is an integral component of Rho/ROCK signaling in regulating the pathological conditions of asthma and thus SUMOylation is an additional target for the therapeutic intervention of this disease. Allergic asthma is characterized by goblet cell metaplasia. Here, the authors show protein SUMOylation contributes to goblet cell metaplasia and SUMOylation-mediated ROCK2 activation is an integral component of Rho/ROCK signalling pathway in controlling the airway goblet cell metaplasia. [ABSTRACT FROM AUTHOR]

The FeCoS2/rGO was synthesized by a one-step hydrothermal method, which has the advantages of environmental friendliness and low cost. Dense and homogeneous FeCoS2 nanodots are dispersed in the reduced graphene oxide flakes, which is beneficial to improve catalytic activity. Compared with FeS2/rGO, FeCoS2/rGO exhibits much higher initial discharge capacity and much better capacity retention ratio. The lower activation energy and the relatively narrow peak shape and small reduction/oxidation peak spacing show that FeCoS2/rGO have better catalytic activity than FeS2/rGO. It can be also confirmed by first-principles calculation that the adsorption energy of the Fe site (− 1.8334 eV) and the Co site (− 1.7539 eV) on the FeCoS2 surface is better than that of FeS2. So, the synergistic reaction of Fe and Co will adjust microregional electron density and change binding energy to polysulfides. [ABSTRACT FROM AUTHOR]

Multicolor-tunable materials have attracted extensive interest due to their unique advantages in applications of lighting and displays. In this paper, energy transfer from Ce3+ to Tb3+ occurred and the effective energy transfer efficiency (ηETE) of Ce3+-Tb3+ has been calculated to be as high as 36%. To obtain multicolor-tunable emissions, Eu3+ ions were successfully introduced into Ce3+–Tb3+ codoped Sr3La6(SiO4)6 samples. Furthermore, an energy transfer process from Ce3+ to Eu3+ ions has also been demonstrated by an energy transfer bridge of Tb3+. Meanwhile, we achieved the precise adjustment of purple, green, orange and red emissions of Sr3La6(SiO4)6: Ce3+, Tb3+, and Sr3La6(SiO4)6: Ce3+, Tb3+, Eu3+. In addition, Sr3La6(SiO4)6: Ce3+, Tb3+, Eu3+ phosphors exhibited a good thermal stability: their integrated emission intensities at 450 K still kept more than 90% of their initial intensity at room temperature. Therefore, these results might provide a novel multicolor-tunable phosphor for lighting and display application. [ABSTRACT FROM AUTHOR]

Dy3+ ions doped inorganic materials have attracted extensive attentions for their peculiar white emission and simple preparing process. However, Dy3+ ions in these materials have low emission intensity due to the weak absorption in ultraviolet spectral region. Ce3+ ions in most of inorganic compounds show a broad emission in ultra-violet region. Thus, Ce3+ is an effective sensitizer for Dy3+. In this work, a sequence of novel white light-emitting phosphors LaAl2.03B4O10.54: Ce3+/Dy3+ was synthesized by high-temperature solid-state reaction method. Under the excitation at 310 nm, the luminescence properties and energy transfer behavior were investigated in detail for Ce3+/Dy3+ co-doped LaAl2.03B4O10.54 phosphors. The energy transfer efficiency from Ce3+ to Dy3+ was calculated to be 56% with the quadrupole–quadrupole interaction mode. The emitting color of the samples can be modulated from (0.210, 0.123) to white region (0.263, 0.237) by properly changing the doping concentration of Dy3+. The results in this work indicate that the color tunable LaAl2.03B4O10.54: Ce3+/Dy3+ phosphors may be a potential single component phosphor in the field of wLEDs. [ABSTRACT FROM AUTHOR]

Dy3+-doped Ca9NaZn(PO4)7 has been synthesized by high-temperature solid-state reaction. X-ray diffraction analysis revealed that the obtained phosphors existed as single phase. Doping with Dy3+ at low concentration had no obvious effect on the crystal structure of the host. Dy3+-doped samples showed strong emission at approximately 480 nm and 571 nm under excitation at 350 nm. The blue and yellow emissions showed almost the peak intensity. The combination of blue and yellow light formed white light. The color coordinates (0.323, 0.372) of the composite light are located in the white light region. The optimum doping concentration of Dy3+ ions was experimentally determined to be 10 mol.%. The concentration quenching mechanism was ascertained to be electric dipole-dipole interaction among Dy3+ ions. The obtained phosphors exhibited good thermal stability. These results indicate potential applications as single-phase white light-emitting phosphors. [ABSTRACT FROM AUTHOR]

A series of un-doped and Dy3+ doped Ca9Gd(PO4)7 phosphors were synthesized by traditional solid state reactions. X-ray diffraction analysis and scanning electronic microscope observation were carried out to examine the phase formation and morphology of prepared samples. Emission spectra under the excitation at 350 nm ultraviolet light turn out that main emission bands are located at 480, 570 and 659 nm, which can be assigned to the optical transitions 4F9/2 → 6H15/2, 4F9/2 → 6H13/2 and 4F9/2 → 6H11/2 of Dy3+, respectively. Comparison of emission spectra upon excitation of 273 nm between un-doped and Dy3+ doped Ca9Gd(PO4)7 samples proves that effective energy transfer from Gd3+ to Dy3+ takes place. The Commission International de I’Eclairage color coordinates (0.272, 0.322) located in white region was achieved. With the increasing doping concentration of Dy3+, concentration quenching is clearly observed and the optimum content of doped Dy3+ is 0.12. The mechanism of concentration quenching is experimentally ascertained to be electric dipole-dipole interactions. The study of quantum efficiency and thermal stability shows that our phosphors have higher quantum efficiency and better thermal stability. This work indicates that our phosphors have potential applications in white light-emitting diodes. [ABSTRACT FROM AUTHOR]

Stoichiometric phosphors SrGaLaEuGeO ( x = 0, 0.2, 0.4, 0.6, 0.8 and 1) were synthesized via traditional solid state reactions. The X-ray diffraction patterns of the samples reveal that Eu can be successfully alloyed in SrGaLaEuGeO up to x = 1. SrGaLaGeO and SrGaEuGeO can form solid solution at any ratio. The composition of solid solution can be expressed as SrGaLaEuGeO (0 ≤ x ≤ 1). The photoluminescence properties of SrGaLaEuGeO are discussed in detail. Eu doped phosphors can emit red light under the excitation of near ultraviolet light because of the emission from D → F (j = 0, 1, 2, 3, 4) transition. The typical chromaticity coordinates of Eu doped phosphors are in red area, which are close to the standard values of red color chromaticity coordinate (0.67, 0.33) stipulated by National Television Standards Committee. The integral strength from 570 to 750 nm of SrGaEuGeO is about 2.5 times of that of commercially obtained YOS: 0.1Eu under the excitation at 393 nm. Present research indicates that SrGaLaEuGeO is a promising phosphor for white light emitting diodes. [ABSTRACT FROM AUTHOR]

A series of novel red-emitting phosphors CaLa(PO): xEu were synthesized by high-temperature solid state reactions. The photoluminescence excitation and photoluminescence spectra of these phosphors were investigated in detail. O-Eu charge transfer band peaking at about 261 nm is dominant in the PLE spectra of Eu-doped CaLa(PO), indicating that the phosphors are suitable for tricolor fluorescent lamps. The phosphors also show a good absorption in near ultraviolet (around 395 nm) and blue (around 465 nm) spectral region, which indicates that it can be pumped with NUV and blue chips for white light-emitting diodes. The transition of D → F of Eu in this lattice can emit bright red light. CaLa(PO) could accommodate a large amount of Eu with an optimal concentration of 60 mol%. The dipole-dipole interaction between Eu is the dominant mechanism for concentration quenching of Eu. The calculated color coordinates lie in red region ( x = 0.64, y = 0.36), which is close to YO: 0.05Eu ( x = 0.65, y = 0.34). The integral emission intensity of CaLa(PO): 0.6Eu is 1.9 times stronger than that of widely used commercial red phosphor YO: 0.05Eu. All these results indicate that Eu-doped CaLa(PO) is a promising red-emitting phosphor which can be used in tricolor fluorescent lamps and white light-emitting diodes . [ABSTRACT FROM AUTHOR]

Research in biology and medicine is a rapidly expanding field incorporating some of the most fundamental questions concerning structure, function, and purpose. The forefront of new research demands access to advanced techniques and instrumentation capable of probing these unanswered questions. Over the past several decades, nano-scale materials and devices ranging from quasi-one dimensional quantum dots to two dimensional graphene sheets have been engineered and have found applications in nano-bio imaging and spectroscopy. In this review, the incorporation of nanomaterials into three influential spectroscopic and microscopic techniques including fluorescence microscopy, surface plasmon resonance, and sum frequency generation will be introduced. Fluorescence imaging has visualized nanomaterials as compliments or replacements to comparable organic fluorphores, act as a quencher for FRET-based sensing, and serve as a nanoscaffold for molecular beacons. Their versatility in coating materials makes nanomaterials an excellent targeting molecule for any cellular macromolecule or structure. In addition to the targeting capabilities of nanomaterials in fluorescence imaging, surface plasmon resonance has incorporated nanomaterials for applications in signal enhancement, selectivity of target molecules, and the development of more refined and accurate detection. Functionalized nanoparticles enhance the capabilities of sum frequency generation vibrational spectroscopy by providing unique surface chemistry which alters target molecule interactions and orientations. In summary, the incorporation of nanomaterials has greatly enhanced the field of biology and medicine and has allowed for the continual advancement of not only research but instrument development. [ABSTRACT FROM AUTHOR]

We present a two-dimensional (2D) parity-time-symmetric (PT-symmetry) phononic crystals (PCs) with balanced gain and loss medium. Using the super cell method of rectangular lattice, we exhibit the thresholdless spontaneous PT-symmetry breaking in the band structure. The numerical results show that the asymmetric scattering properties obviously occur in a non-Hermitian system. At two specific incident frequencies, unidirectional reflectionless and perfect transmission behaviors exist individually in opposite directions, which are accompanied by a phase transition of π. Based on the generalized Snell's law, combining such a PT-symmetric medium, we design a novel metamaterial crystal for PT-symmetric acoustic flat focusing. Its focus frequency can also be modulated by the gain/loss parameter. The novel flat focusing based on the PT-symmetry that we propose opens a new door for high-dimensional applications of non-Hermitian metamaterials in acoustic wave manipulation. [ABSTRACT FROM AUTHOR]

A series of novel white light-emitting LaAl2.03B4O10.54: Dy3+ phosphors for light-emitting diode applications were synthesized by high-temperature solid-state reactions. The results of X-ray diffraction measurement indicate that the crystal structure of the phosphors is LaAl2.03B4O10.54. The photoluminescence spectra of Dy3+-doped samples under the excitation at 347 nm consist of two main groups of emission lines peaking at 480 and 571 nm, which can be assigned to the optical transitions 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 of Dy3+, respectively. Based on the recorded UV-visible diffuse reflectance spectra, the values of the optical band gaps of LaAl2.03B4O10.54 and La0.96Al2.03B4O10.54: 0.04 Dy3+ were ascertained to be 3.87 and 3.62 eV, respectively. The decay lifetimes decreases with the increasing doping concentration of Dy3+. The Commission International de I’Eclairage color coordinates of Dy3+-doped samples fall in the white region. The study about the photoluminescence spectra at rising temperature shows that our phosphors own excellent thermal stability. All these investigation results indicate that LaAl2.03B4O10.54: Dy3+ as white light-emitting phosphor has potential applications in white light-emitting diodes. [ABSTRACT FROM AUTHOR]

A series of novel white light-emitting LaAl2.03B4O10.54: Dy3+ phosphors for light-emitting diode applications were synthesized by high-temperature solid-state reactions. The results of X-ray diffraction measurement indicate that the crystal structure of the phosphors is LaAl2.03B4O10.54. The photoluminescence spectra of Dy3+-doped samples under the excitation at 347 nm consist of two main groups of emission lines peaking at 480 and 571 nm, which can be assigned to the optical transitions 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 of Dy3+, respectively. Based on the recorded UV-visible diffuse reflectance spectra, the values of the optical band gaps of LaAl2.03B4O10.54 and La0.96Al2.03B4O10.54: 0.04 Dy3+ were ascertained to be 3.87 and 3.62 eV, respectively. The decay lifetimes decreases with the increasing doping concentration of Dy3+. The Commission International de I’Eclairage color coordinates of Dy3+-doped samples fall in the white region. The study about the photoluminescence spectra at rising temperature shows that our phosphors own excellent thermal stability. All these investigation results indicate that LaAl2.03B4O10.54: Dy3+ as white light-emitting phosphor has potential applications in white light-emitting diodes. [ABSTRACT FROM AUTHOR]