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PURPOSE OF REVIEW: This review aimed to identify and describe evidence published in the past 3 years from trials of psychosocial support programs for children and adolescents affected by natural disasters. RECENT FINDINGS: Previous reviews have indicated these programs are beneficial overall. Positive impacts were documented in school-based programs conducted by trained teachers and paraprofessionals with stronger effects achieved by more qualified professionals. The review found supporting evidence for positive impacts of post-disaster psychosocial programs. However, the strength of evidence is limited due to heterogeneity in interventions and evaluations. The stepped care model was found to be useful in differentiating between programs and level of available evidence. Hobfoll's five essential elements of mass trauma intervention provide an additional means of guiding program content and assessments, particularly for universal programs. Identified gaps in evidence included groups likely to be at most risk: preschool children, ethnically diverse groups, those with disability, and social disadvantage. There were promising indications of program benefits for groups with repeated exposure to natural disasters.

PURPOSE: Rapid advances in technology create opportunities for adolescents to influence practice and policy in health and other domains. Technology can support the scaling of Youth-Led Participatory Action Research (YPAR), in which adolescents conduct research to improve issues that affect them. We present the first known published systematic review of the use of technology to scale YPAR. METHODS: A systematic review of the empirical literature was conducted from 2000 to 2018 using databases PsycARTICLES, PsycINFO, and PubMed. The review included peer-reviewed articles of YPAR studies involving adolescents (aged 10-19 years) using technology for scaling. Appraisal of papers included the role of technology and consistency with YPAR principles. RESULTS: Nine peer-reviewed YPAR publications focusing on a range of health issues with adolescents aged 11-19 years were identified. Technology included Facebook (most common), Twitter, Instagram, Skype, e-mail, blogs, and personalized mapping applications. Overall, technology was primarily used for adolescent participants to gather data. The appraisal revealed the complexities inherent in conducting YPAR using technology across multiple sites, with different adults in supportive roles and varying levels of opportunities for adolescent engagement. CONCLUSIONS: This review provides insights at the intersection of youth-led research and technology, highlighting opportunities in a changing technological landscape and the challenges of YPAR at scale.

Phosphors of (Y0.75Gd0.25)(2)O-3:Eu3+ (5 at.%) have been prepared through soft chemistry routes. Conversion of the starting nitrates mixture into oxide is performed through two approaches: (a) hydrothermal treatment (HT) at 200 degrees C/3 h of an ammonium hydrogen carbonate precipitated mixture and (b) by thermally decomposition of pure nitrate precursor solution at 900 degrees C in dispersed phase (aerosol) within a tubular flow reactor by spray pyrolysis process (SP). The powders are additionally thermally treated at different temperatures: 600, 1000, and 1100 degrees C for either 3 or 12 h. HT-derived particles present exclusively one-dimensional morphology (nanorods) up to the temperatures of 600 degrees C, while the leaf-like particles start to grow afterward. SP-derived particles maintain their spherical shape up to the temperatures of 1100 degrees C. These submicron sized spheres were actually composed of randomly aggregated nanoparticles. All powders exhibits cubic Ia-3 structure (Y0.75Gd0.25)(2)O-3:Eu and have improved optical characteristics due to their nanocrystalline nature. The detailed study of the influence of structural and morphological powder characteristics on their emission properties is performed based on the results of X-ray powder diffractometry, scanning electron microscopy, X-ray energy dispersive spectroscopy, transmission electron microscopy, and photoluminescence measurements.

Phosphors of (Y0.75Gd0.25)(2)O-3:Eu3+ (5 at.%) have been prepared through soft chemistry routes. Conversion of the starting nitrates mixture into oxide is performed through two approaches: (a) hydrothermal treatment (HT) at 200 degrees C/3 h of an ammonium hydrogen carbonate precipitated mixture and (b) by thermally decomposition of pure nitrate precursor solution at 900 degrees C in dispersed phase (aerosol) within a tubular flow reactor by spray pyrolysis process (SP). The powders are additionally thermally treated at different temperatures: 600, 1000, and 1100 degrees C for either 3 or 12 h. HT-derived particles present exclusively one-dimensional morphology (nanorods) up to the temperatures of 600 degrees C, while the leaf-like particles start to grow afterward. SP-derived particles maintain their spherical shape up to the temperatures of 1100 degrees C. These submicron sized spheres were actually composed of randomly aggregated nanoparticles. All powders exhibits cubic Ia-3 structure (Y0.75Gd0.25)(2)O-3:Eu and have improved optical characteristics due to their nanocrystalline nature. The detailed study of the influence of structural and morphological powder characteristics on their emission properties is performed based on the results of X-ray powder diffractometry, scanning electron microscopy, X-ray energy dispersive spectroscopy, transmission electron microscopy, and photoluminescence measurements.

Cerium-doped yttrium aluminum garnet (YAG:Ce3+) powder phosphor is synthesized via spray pyrolysis of polymeric precursor solution obtained by dissolving the corresponding nitrates in ethylenediaminetetraacetic acid (EDTA). Ultrasonically generated aerosol droplets are decomposed at 600 degrees C in argon atmosphere. Following the initial attempt in providing pure YAG:Ce3+, phase generation the particles were additionally thermally treated for 3 h in air at 1000 and 1100 degrees C. The powder morphology is followed with scanning electron microscopy (SEM), while inner particle structure is analysed by analytical and high-resolution transmission electron microscopy (TEM). Phase identification is performed by X-ray powder diffraction (XRPD) based on which a structural refinement through Rietveld method was done. The spherical submicronic particles have grained sub-structure comprising clustered garnet monocrystals sized below 100 nm. The YAG:Ce3+ emission shows wide peak in the range 470-600 nm with the maximum near 520 nm. (C) 2009 Elsevier Ltd. All rights reserved.

Red emitting Y2O3:Eu3+ (5 and 10 at.%) submicronic particles were synthesized through ultrasonic spray pyrolysis method from the pure nitrate solutions at 900 degrees C. The employed synthesis conditions (gradual increase of temperature within triple zone reactor and extended residence time) assured formation of spherical, dense, non-agglomerated particles that are nanostructured (crystallite size similar to 20 nm). The as-prepared powders were additionally thermally treated at temperatures up to 1200 degrees C. A bcc la-3 cubic phase presence and exceptional powder morphological features were maintained with heating and are followed with particle structural changes (crystallite growth up to 130 nm). Emission spectra were studied after excitation with 393 nm wavelength and together with the decay lifetimes for Eu3+ ion D-5(0) and D-5(1) levels revealed the effect of powder nanocrystalline nature on its luminescent properties. The emission spectra showed typical Eu3+ D-5(0)- GT F-7(i) (i = 0, 1, 2, 3, 4) transitions with dominant red emission at 611 nm, while the lifetime measurements revealed the quenching effect with the rise of dopant concentration and its more consistent distribution into host lattice due to the thermal treatment. (C) 2010 Elsevier B.V. All rights reserved.

Cerium-doped yttrium aluminum garnet (YAG:Ce3+) powder phosphor is synthesized via spray pyrolysis of polymeric precursor solution obtained by dissolving the corresponding nitrates in ethylenediaminetetraacetic acid (EDTA). Ultrasonically generated aerosol droplets are decomposed at 600 degrees C in argon atmosphere. Following the initial attempt in providing pure YAG:Ce3+, phase generation the particles were additionally thermally treated for 3 h in air at 1000 and 1100 degrees C. The powder morphology is followed with scanning electron microscopy (SEM), while inner particle structure is analysed by analytical and high-resolution transmission electron microscopy (TEM). Phase identification is performed by X-ray powder diffraction (XRPD) based on which a structural refinement through Rietveld method was done. The spherical submicronic particles have grained sub-structure comprising clustered garnet monocrystals sized below 100 nm. The YAG:Ce3+ emission shows wide peak in the range 470-600 nm with the maximum near 520 nm. (C) 2009 Elsevier Ltd. All rights reserved.

[ES] Los óxidos de gadolinio y de ytrio dopados con europio (Gd2O3:Eu, Y2O3:Eu) presentan propiedades luminiscentes. Dichas propiedades mejoran con la utilización de materiales nanoestructurados, con geometría esférica y estrecha distribución de tamaño de partícula. Además, las propiedades luminiscentes son favorecidas cuando se tiene una distribución homogénea de los centros dopantes en la matriz del material anfitrión. En este estudio se presenta la síntesis y caracterización de óxidos de gadolinio y de ytrio dopados con diferentes proporciones de Eu. Se sintetizaron partículas nanoestructuradas mediante la técnica de Spray Pirólisis en un horno tubular a distintas temperaturas, las cuales fueron sometidas posteriormente a diferentes tratamientos isotérmicos. La caracterización morfológica, química y estructural de las nanopartículas se realizó por microscopia electrónica de barrido (MEB-EDS), microscopía electrónica de transmisión (MET) y difracción de rayos-X (DRX)., [EN] Gadolinium and Ytrium oxides doped with europium (Gd2O3:Eu, Y2O3:Eu) have luminiscent properties. Such properties are improved with the use of nanostructured materials with spherical geometry and narrow particle size distribution. Besides, luminescent properties enhance with a homogeneous distribution of dopant centers in the host matrix material. In this paper the synthesis and characterization of gadolinium and yttrium doped with different proportions of Europium are shown. Nanostructured particles were synthesized through Spray Pyrolysis route in a tubular furnace at different temperatures, and subjected to different post-thermal treatments. Scanning electron microscopy (SEM-EDS), transmission electron microscopy (TEM) and X-ray diffractometry (XRD) were used for the morphological, chemical and structural characterization of the nanoparticles.