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The Sn single doped and Sn/rare-earth (RE) ions (Eu3+, Dy3+, and Sm3+) co-doped Na 3 Gd(VO 4) 2 (NGVO) materials were synthesized using a sol-gel method by mixing stoichiometric amounts of the precursors. All the samples gave intense diffraction peaks without any shift in the 2θ values and did not show any impurity phases. The scanning electron microscope images of Sn and RE ions co-doped samples did not show significant changes with the dopant ions, and the elements present in the samples was analyzed with energy dispersive X-ray spectrometry. Introducing Sn into the V site showed enhanced optical characteristics due to the formation of oxygen vacancies and lattice distortions in the host lattice. Similarly, when the NGVO host was co-doped with Sn and RE ions, the optical properties of the RE were enhanced. Temperature-dependent optical properties of the Sn co-doped NGVO: RE samples were also fortified due to the Sn co-doping and showed an increase in thermal activation energy values when compared with NGVO: RE samples. [ABSTRACT FROM AUTHOR]

An essential key to enhance the redox chemistry of battery-type materials is to construct rational design of nanoarchitectures with high electrochemical activity. Herein, we reported a hierarchical composite consisting of bilayered nickel hydroxide carbonate nanoplates-decorated nanoflowers on nickel foam (NHC NPs@NFs/Ni foam) via a facile homogeneous precipitation method for use as an effective cathode in hybrid supercapacitors (HSCs). Under controlled growth time (4 h), the bilayered NHC NPs@NFs with hierarchical alignment were spontaneously crystallized on Ni foam. The as-preapared hybrid structure greatly enhanced the electroactive surface area and enabled the rapid redox chemistry in alkaline electrolyte. Notably, the hybrid NHC NPs@NFs/Ni foam delivered a maximum areal capacity of 727.4 μAh/cm 2 at 2 mA/cm 2 and it is relatively higher than its oxide form (76.6 μAh/cm 2 ) in a three-electrode system. Also, a pouch-type HSC with bilayered NHC NPs@NFs/Ni foam and porous carbon electrodes was fabricated, which demonstrated superior energy storage performance in terms of capacitance (1445.8 mF/cm 2 ), energy density (0.506 mWh/cm 2 ), power density (35.675 mW/cm 2 ) and cycling stability (89.4%). Furthermore, the self-charging power station consisting of a solar cell for energy conversion and the HSCs for energy storage was also assembled to operate the portable electronic displays and wall clock effectively for long time. This facile approach for the cost-effective fabrication of hierarchically designed nanomaterials paves a path for the development of high-performance hybrid supercapacitors. [ABSTRACT FROM AUTHOR]

The Sr 3 SiO 5 : Ce 3+ /Dy 3+ phosphors were prepared via a citrate assisted sol-gel method. The prepared samples were characterized by X-ray diffraction pattern, scanning electron microscopy, Fourier transform infrared spectroscopy and fluorescence spectroscopy. When excited with near-ultraviolet (NUV) (360 nm) irradiation, the photoluminescence emission spectra showed a broad band blue emission of Ce 3+ ions combined with the sharp emission peaks of Dy 3+ ions. Energy transfer occurred between the Ce 3+ and Dy 3+ ions and it increased with the increase of Dy 3+ ion concentration. The luminescence properties of the prepared phosphor materials could be adjusted by changing the concentration ratio of the Ce 3+ and Dy 3+ ions. The prepared phosphor materials also exhibited good thermal stability. [ABSTRACT FROM AUTHOR]

Objective Selection of the method of intubation during complex facial surgeries is a difficult task for the anesthetist because of airway is sharing area and oral or nasal intubation is not preferable, even though, tracheostomy is a worthy alternative; however, it has serious complications. Altemir FH introduced the ‘submental technique’ as a substitute for tracheostomy but it has demonstrated the complications of ‘lingual nerve damage’ and ‘Wharton's duct injuries’. So, the Stoll's approach is the safest option in this scenario. The purpose of the present study was to evaluate ‘Stoll's submandibular method’ as a safest choice to Altemir's technique. Materials and method The study was conducted prospectively in a sample of 42 patients for intra-operative airway management in complex facial surgeries during the period of six years from 2008 to 13 by considering the following objectives: duration of the procedure, and intra-operative and postoperative complications. Results The average time taken for this procedure was 9 min. The complications encountered were superficial skin wound infection in a total of three patients (7%), partial extubation in one case (2%), cuff leakage in one case (2%) and dislodgement of the tube in one case (2%). Conclusion The results of the present study have provided the evidence of Stoll's technique as a safest choice both for Altemir's and tracheostomy in justifiable circumstances because of simple, quick technique associated with negligible complications. So, anesthetist should consider this underutilized technique in complex facial surgeries and it is a valuable option in patients, who underwent tracheostomy in previous surgeries. [ABSTRACT FROM AUTHOR]

The rare-earth ions (Eu 3+ , Dy 3+ ) doped Y 6 WO 12 phosphors were prepared by a citrate-based sol–gel method. The morphologies and structural properties of the as-prepared and doped samples were analyzed by scanning electron microscope images and X-ray diffraction patterns. The luminescent properties were studied by examining the excitation and emission spectra of the samples. The Eu 3+ and Dy 3+ ions doped samples exhibited their characteristic emission bands in the visible region under ultraviolet light excitation. The temperature-dependent photoluminescence (PL) properties of the samples were also investigated. The PL spectra of the synthesized samples by the sol–gel method were compared with those of the bulk sample prepared by a solid-state reaction. Similarly, the Commission International de I’Eclairage chromaticity coordinates and the decay times of Y 6 WO 12 :Eu 3+ (3 mol%) and Y 6 WO 12 :Dy 3+ (2 mol%) phosphors were studied. [ABSTRACT FROM AUTHOR]

The AgLa(PO3)4 phosphors activated with trivalent rare-earth (Eu3+, Tb3+) ions were prepared by a sol-gel synthesis method. The crystal structure of the compound was studied by X-ray diffraction patterns and found to be crystallized in the monoclinic system with a space group P21/c, indicating the calculated lattice parameters of a = 10.08 Å, b = 13.12 Å, and c = 7.314 Å. The Fourier-transform infrared spectrum, photoluminescence excitation/emission spectra, and decay curves were examined to study the optical properties. The analysis of the Eu3+ ions related emission spectrum revealed the presence of highly symmetric sites for the activator ions. The Tb3+ ions related emission spectrum exhibited a 5D3 emission due to the prolonged calcination at high temperatures, which reduces the residual hydroxyl ions. The optical properties show that this host material is suitable for phosphor materials and laser crystals. [ABSTRACT FROM AUTHOR]

Abstract We report the synthesis and luminescence properties of the rare-earth ions doped Ba 2 LaV 3 O 11 phosphors. The Dy3+ and Eu3+ ions single doped and Dy3+/Eu3+ ions co-doped Ba 2 LaV3O 11 phosphors were synthesized via a citrate-based sol-gel method. The surface morphology, phase purity, photoluminescence properties and thermal stability of the synthesized phosphors were determined from the X-ray diffractometer, field-emission scanning electron microscope and spectrofluorometer, respectively. The obtained results indicate that the prepared phosphor material was crystallized in monoclinic phase with the space group P 2 1 / c (14) and the diffraction peaks were well matched with the standard JCPDS (#40-0105) card values. Under charge transfer band excitation wavelengths, the Eu3+ (277 nm) and Dy3+ (274 nm) single doped phosphor samples exhibited characteristic red and yellow emissions, respectively. Meanwhile, the Dy3+/Eu3+ co-doped phosphor samples showed near white-light emission. Graphical abstract Image 1 Highlights • Rare-earth ions doped Ba 2 LaV 3 O 11 phosphors were synthesized by a citrate-based sol-gel method. • Eu3+, Dy3+ single and co-doped phosphors showed green, red, yellow and warm white emissions, respectively. • The energy transfer mechanism among the (VO 4)3-, Eu3+ and Dy3+ was discussed. • The prepared single and co-doped phosphors can be utilized as luminescent materials for WLEDs. [ABSTRACT FROM AUTHOR]

Highlights • BTO was synthesized by a facile, eco-friendly, and cost-effective solid-state reaction. • Performance of PNG is improved by Ag-NWs and BTO embadded composites. • Particularly, the risky and high-field poling process was avoided. • The PNG is employed to effectively harvest the energy from automotive vehicle motions. • The flexibility of PNG was also examined and used to detect human hand movement. Abstract Piezoelectric nanogenerators (PNGs) is one of the promising technologies to convert mechanical energies into electricity for driving various mobile/portable electronic devices. Generally, the electrical output performance of PNGs is enhanced by electrical poling or annealing treatment, which involves high voltage and temperature techniques. Herein, we successfully demonstrated a flexible PNG designed by the barium titanate embedded polyvinylidene difluoride (i.e., BaTiO 3 /PVDF) composite film and attained a significant output performance with avoiding electrical poling process. These barium titanate micro stone-like architectures (BTO-MSs) were synthesized by a facile, eco-friendly, and cost-effective solid-state reaction. In addition, the output performance of PNG is further improved by dispersing the silver nanowires (Ag-NWs) as a conducting supplement filler along with the BTO-MSs into the PVDF matrix. Resultantly, the PNG with Ag-NWs/BTO/PVDF composite film exhibited a high open-circuit voltage (V OC) of ∼ 14 V and short-circuit current (I SC) of ∼ 0.96 μA compared to the PNG with only BTO/PVDF (V OC /I SC ∼ 11 V/0.78 μA) upon the application of a low pushing force of 3 N, cyclic pushing-releasing frequency of 5 Hz. Additionally, the effect of external load resistance, pushing force, and frequency on the electrical output performance of PNGs was investigated, including its mechanical stability and durability. Finally, an optimized PNG was employed to efficiently harvest/detect the mechanical energy from automotive vehicle motion and human body movements. [ABSTRACT FROM AUTHOR]

Upconversion Sr 2 (Gd .98- x Er .02 Yb x ) 8 Si 6 O 26 (SGSO:2Er 3+ / x Yb 3+ ) phosphor materials were synthesized using a citrate sol-gel process. X-ray diffraction patterns confirmed their hexagonal structure. Field emission scanning electron microscopy images of SGSO:2Er 3+ / x Yb 3+ phosphors depicted submicron particles. The enhanced upconversion luminescence properties of SGSO:2Er 3+ / x Yb 3+ phosphors were analysed as a function of Yb 3+ ion concentration and laser power. The energy transfer induced enhanced emission of the Er 3+ / Yb 3+ ions co-doped SGSO phosphors was ascribed to multi-phonon relaxation. The calculated chromaticity coordinates of the SGSO:2Er 3+ / x Yb 3+ phosphors showed emissions could be tuned by changing Yb 3+ ion concentration. Optimized sample exhibited the chromaticity coordinate values near to the ultra-high definition television standard green emission coordinates. [ABSTRACT FROM AUTHOR]

We synthesized the trivalent europium ions (Eu 3+ ) doped lanthanum aluminate (LaAlO 3 , LAO) nanophosphors by a solvothermal method. Their structural, morphological, and luminescent properties were systematically investigated. The obtained nanoparticles possessed single nanocrystallinity with a rhombohedral structure. For the excitation originating from the charge transfer band (O 2- to Eu 3+ ions) under 320 nm illumination, the featured emissions of Eu 3+ ions were detected in all the compounds. The optimum doping concentration of Eu 3+ ions in LAO was about 9 mol% and the concentration quenching was dominated by dipole-dipole interaction. Furthermore, the Judd-Ofelt (J-O) theory was used to estimate the J-O intensity parameters. Based on the temperature-dependent PL emission spectra, the thermal stability was analyzed and the activation energy was obtained to be 0.234 eV. Meanwhile, the decay time, color coordinate/purity, and cathodoluminescence behaviors of the synthesized nanophosphors were also studied. These characteristics make the Eu 3+ -doped LAO nanoparticles a promising red-emitting phosphor for both ultraviolet-based white light-emitting diodes and field-emission displays. [ABSTRACT FROM AUTHOR]

Epilepsy is a neurological disorder characterized by an enduring predisposition to generate and aggravate epileptic seizures affecting around 1% of global population making it a serious health concern. Despite the recent advances in epilepsy research, no disease-modifying treatment able to terminate epileptogenesis have been reported yet reflecting the complexity in understanding the disease pathogenesis. To overcome the current treatment gap against epilepsy, one effective approach is to explore anti-epileptic effects from a drug that are approved to treat non-epileptic diseases. In this regard, Metformin emerged as an ideal candidate which is a first line treatment option for type 2 diabetes mellitus (T2DM), has conferred neuroprotection in several in vivo neurological disorders such as Alzheimer's diseases (AD), Parkinson's disease (PD), Stroke, Huntington's diseases (HD) including epilepsy. In addition, Metformin has ameliorated cognitive alteration, learning and memory induced by epilepsy as well as in animal model of AD. Herein, we review the promising findings demonstrated upon Metformin treatment against animal model of epilepsy however, the precise underlying mechanism of anti-epileptic potential of Metformin is not well understood. However, there is a growing understanding that Metformin demonstrates its anti-epileptic effect mainly via ameliorating brain oxidative damage, activation of AMPK, inhibition of mTOR pathway, downregulation of α-synuclein, reducing apoptosis, downregulation of BDNF and TrkB level. These reflects that Metformin being non-anti-epileptic drug (AED) has a potential to ameliorate the cellular pathways that were impaired in epilepsy reflecting its therapeutical potential against epileptic seizure that might plausibly overcome the limitations of today epilepsy treatment. Unlabelled Image [ABSTRACT FROM AUTHOR]

• The pristine and neodymium-doped Mn 2 O 3 3D-microspheres were successfully synthesized. • The optimum Nd5%-Mn 2 O 3 3D-MSs exhibited remarkable high specific capacitance of 862.14 F g−1 and long cycle stability of 97.30% after 2000 cycles. • The assembled pouch-type HSCs significantly provide a maximum energy density of 32.26 Wh kg−1 at power density 800 W kg−1. • This work demonstrated that the mesoporous, oxygen vacancy and robust structure assist to achieve high energy density and long cycle life. Synthesis of high energy density and long durability electrode materials are huge urgency for futuristic hybrid supercapacitors (HSCs). In the present work, self-assembled three-dimensional (3D)-mesoporous regimented pristine and neodymium (Nd) doped α-Mn 2 O 3 microspheres (MSs) are prepared by simple hydrothermal method. Due to uniform morphology, presence of oxygen vacancies, mesoporous robust structure, and optimum doping (Nd5%-doped Mn 2 O 3 3D-MSs) offers a high specific capacitance of 862.14 F g−1 (431.07 C g−1) at 0.5 A g−1 with superior cycling retention of 97.30% after 2000 cycles. Additionally, a pouch-type HSC device is fabricated using Nd5%-Mn 2 O 3 3D-MSs as a battery-type positive electrode and activated carbon (AC) as a capacitive-type negative electrode. The fabricated device delivers a maximum energy density of 32.26 Wh kg−1 at a power density of 800 W kg−1 with superior cyclic retention and exhibit a little loss of 4.56% after 10,000 cycles. This superior performance is due to robust microstructures that can alleviate swelling and shrinking of active material at cycling test. Two pouch-type HSCs are connected in series to power light-emitting diodes (LEDs) for real-time applicability. Overall, this study demonstrates that rational doping, porous architecture, oxygen vacancies, and robust micro-nano structure greatly assist to achieve high energy density as well as long life HSCs devices. Image, graphical abstract [ABSTRACT FROM AUTHOR]