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1.
Healthcare (Basel) ; 11(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37372813

RESUMO

Evidence suggests that adolescents respond positively to simple, early interventions, including psychosocial support and educational interventions, even when offered in non-clinical settings. Cinematherapy can help manage life challenges, develop new skills, increase awareness, and offer new ways of thinking about specific problems. This pilot trial was conducted in Italy, aiming to investigate the effects of a six-week filmmaking course on the psychological well-being of adolescents (N = 52) with emotional/behavioural problems and neurodevelopmental disorders. At the end of the project, most participants showed improvements mostly in social skills, such as social cognition (p = 0.049), communication (p = 0.009), and motivation (p = 0.03), detected using the SRS Social Responsiveness Scale. In addition, social awareness (p = 0.001) increased in all patients. Statistically significant differences resulted in four sub-scales of Youth Self-Report Scale: withdrawn/depressed (p = 0.007), social problems (p = 0.003), thought problems (p < 0.001), and rule-breaking behaviour (p = 0.03); these results showed a decrease in emotional and behavioural problems. This study is an innovative therapeutic and educational approach based on the filmmaking art. This research can offer an empirical basis for the effectiveness of alternative therapeutic tools in child and adolescent psychiatric disorders. At the same time, it can be replicated in broader contexts (e.g., school and communities) to promote children's psychological well-being.

2.
Tumori ; 109(3): 342-343, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36964669

Assuntos
Chuva , Humanos
3.
Small ; 17(49): e2101666, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34309208

RESUMO

Methods for the fabrication of thin films with well controlled structure and properties are of great importance for the development of functional devices for a large range of applications. SILAR, the acronym for Successive Ionic Layer Adsorption and Reaction, is an evolution and combination of two other deposition methods, the Atomic Layer Deposition and Chemical Bath Deposition. Due to a relative simplicity and low cost, this method has gained increasing interest in the scientific community. There are, however, several aspects related to the influence of the many parameters involved, which deserve further deepening. In this review article, the basis of the method, its application to the fabrication of thin films, the importance of experimental parameters, and some recent advances in the application of oxide films are reviewed. At first the fundamental theoretical bases and experimental concepts of SILAR are discussed. Then, the fabrication of chalcogenides and metal oxides is reviewed, with special emphasis to metal oxides, trying to extract general information on the effect of experimental parameters on structural, morphological and functional properties. Finally, recent advances in the application of oxide films prepared by SILAR are described, focusing on supercapacitors, transparent electrodes, solar cells, and photoelectrochemical devices.

4.
Nanomaterials (Basel) ; 10(8)2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32751278

RESUMO

Solution processed TiO2 anatase film was used as sensitive layer for H2 detection for two plasmonic sensor configurations: A grating-coupled surface plasmon resonance sensor and a localized surface plasmon resonance sensor with gold nanoparticles. The main purpose of this paper is to elucidate the different H2 response observed for the two types of sensors which can be explained considering the hydrogen dissociation taking place on TiO2 at high temperature and the photocatalytic activity of the gold nanoparticles.

5.
PDA J Pharm Sci Technol ; 72(6): 553-565, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29954923

RESUMO

Delamination, which is the formation of flakes in drug products owing to specific and localized corrosion of glass vials, is a rare but serious problems, on which the FDA (U.S. Food and Drug Administration) put a warning to the pharma industry in 2011. The Technical Committee (TC) TC12 of the International Commission on Glass (ICG) was created in 2012 with the aim to study the problems related to pharma packaging. The first task of TC12 was to address the problem of predicting the propensity of glass vials to delamination, leaving the study of the mechanism(s) of flake formation as a possible future activity. This paper reports on the results obtained in a round robin test, which involved all the labs of the companies represented in the TC.Five types of vials with different expected delamination propensities were tested using a protocol that includes autoclaving at 121°C of vials filled with NaCl solution adjusted to pH 8 with NaOH solution, a coloration test, and ICP-OES determination of Si, B, and Al.Although there was no flake formation, the results showed that the combination of strong coloration at the bottom of the vials and high silicon concentration in the solution is correlated to an observable morphological modification/corrosion of the inner surface of vials in the bottom region. The test protocol is therefore useful for checking the quality of the vials with respect to the propensity to corrosion. Regarding delamination, no direct correlation with the testing results could be obtained yet. The method allows catching differences in the corrosion behavior, mainly between sets of vials with comparable surface:volume.LAY ABSTRACT: The U.S. Food and Drug Administration (FDA) warned the pharma industry about glass delamination inside primary packaging containers. Delamination is a type of glass corrosion that produces glass flakes, which could seriously affect patient health.Fortunately, delamination is a very rare event. On the other hand, it is very difficult to predict its occurrence. In 2012, the International Commission on Glass (ICG) created a Technical Committee (TC) on pharma packaging-with the initial goal to study an easy and reliable test for predicting the propensity of vials to delamination-involving the most important glass vial producers and pharma companies. This paper reports on the results obtained in a round robin test on different types of vials with different expected propensities to delamination. A specific testing protocol was adopted. In none of the vials, including those with an expected high propensity, glass flakes were observed, demonstrating that delamination is a rare event. However, the test is able to predict the occurrence of morphological modification/corrosion of the inner surface of vials in the bottom region. Therefore, the testing protocol is proposed as a method to evaluate differences in the corrosion behavior mainly between sets of vials with comparable surface:volume.


Assuntos
Indústria Farmacêutica/métodos , Embalagem de Medicamentos/normas , Armazenamento de Medicamentos , Vidro/química , Corrosão , Concentração de Íons de Hidrogênio , Preparações Farmacêuticas/análise , Estados Unidos , United States Food and Drug Administration
6.
ACS Appl Mater Interfaces ; 8(44): 30440-30448, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27750418

RESUMO

Highly doped wide band gap metal oxide nanocrystals have recently been proposed as building blocks for applications as transparent electrodes, electrochromics, plasmonics, and optoelectronics in general. Here we demonstrate the application of gallium-doped zinc oxide (GZO) nanocrystals as novel plasmonic and chemiresistive sensors for the detection of hazardous gases including hydrogen (H2) and nitrogen dioxide (NO2). GZO nanocrystals with a tunable surface plasmon resonance in the near-infrared are obtained using a colloidal heat-up synthesis. Thanks to the strong sensitivity of the plasmon resonances to chemical and electrical changes occurring at the surface of the nanocrystals, such optical features can be used to detect the presence of toxic gases. By monitoring the changes in the dopant-induced plasmon resonance in the near-infrared, we demonstrate that GZO thin films prepared depositing an assembly of highly doped GZO colloids are able to optically detect both oxidizing and reducing gases at mild (<100 °C) operating temperatures. Combined optical and electrical measurements show that trivalent dopants within ZnO nanocrystals enhance the gas sensing response compared to undoped ZnO. Moreover, improved sub-ppm of NO2 gas sensitivity is achieved by activating the sensors response through combined purple-blue (λ = 430 nm) light irradiation and mild heating at 75 °C. In addition, these thin films based on degenerately doped semiconductors are highly transparent in the visible range, enabling the fabrication of "invisible" gas sensors. The use of highly doped semiconductive nanocrystals for both IR plasmonic and chemiresistive sensors represent a marked advancement toward the development of highly sensitive and selective devices.

7.
Nanoscale ; 6(3): 1560-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24322302

RESUMO

The preparation of palladium alloy nanoparticles is of great interest for many applications, especially in catalysis. Starting from presynthesized nanoparticles of a less noble metal, a transmetallation reaction involving a redox process at the nanoparticle surface can be exploited to modify the nanoparticle composition and crystalline phase. As an example, monodispersed ε-cobalt and face-centered cubic copper nanoparticles were synthesized in organic solvents at high temperature and the as-formed nanoparticles were reacted with palladium(ii) hexafluoroacetylacetonate resulting in the formation of alloyed nanoparticles whose composition closely follows the reactant ratio. The oxidative state of the nanoparticle surface greatly affects the success of the transmetallation reaction and a reduction treatment was necessary to achieve the desired final product. Electron microscopy and X-ray diffraction showed that for cobalt a limiting palladium content for the ε-phase alloy is found, above which an fcc alloy nucleates, while for copper the fcc crystalline phase is preserved throughout the whole composition range.

8.
J Am Chem Soc ; 135(9): 3439-48, 2013 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-23394063

RESUMO

We present a new colloidal synthesis of gallium-doped zinc oxide nanocrystals that are transparent in the visible and absorb in the near-infrared. Thermal decomposition of zinc stearate and gallium nitrate after hot injection of the precursors in a mixture of organic amines leads to nanocrystals with tunable properties according to gallium amount. Substitutional Ga(3+) ions trigger a plasmonic resonance in the infrared region resulting from an increase in the free electrons concentration. These nanocrystals can be deposited by spin coating, drop casting, and spray coating resulting in homogeneous and high-quality thin films. The optical transmission of the Ga-ZnO nanoparticle assemblies in the visible is greater than 90%, and at the same time, the near-infrared absorption of the nanocrystals is maintained in the films as well. Several strategies to improve the films electrical and optical properties have been presented, such as UV treatments to remove the organic compounds responsible for the observed interparticle resistance and reducing atmosphere treatments on both colloidal solutions and thin films to increase the free carriers concentration, enhancing electrical conductivity and infrared absorption. The electrical resistance of the nanoparticle assemblies is about 30 kΩ/sq for the as-deposited, UV-exposed films, and it drops down to 300 Ω/sq after annealing in forming gas at 450 °C, comparable with state of the art tin-doped indium oxide coatings deposited from nanocrystal inks.


Assuntos
Gálio/química , Tinta , Temperatura , Óxido de Zinco/química , Coloides/química , Tamanho da Partícula , Propriedades de Superfície
9.
Nanoscale ; 3(10): 4109-13, 2011 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-21912805

RESUMO

We report a facile production of an up-converted surface-emitting DFB laser, performed by exploiting the versatility of sol-gel chemistry, the intriguing properties of well designed graded CdSe-CdS-Cd(0.5)Zn(0.5)S-ZnS colloidal quantum dots, and the scalability of nanoimprinting. Our laser prototype operates in the visible region following efficient optical pumping by either direct one-photon excitation or through the up-conversion of near infrared (NIR) light. By achieving cavity mode Q-factors in excess of 650 and retaining high lasing stabilities in air, this work highlights the feasibility of creating integrated lasing devices through solution based methods.


Assuntos
Lasers , Pontos Quânticos , Compostos de Cádmio/química , Géis/química , Compostos de Selênio/química , Sulfetos/química , Compostos de Zinco/química
10.
ACS Appl Mater Interfaces ; 2(5): 1294-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20392071

RESUMO

The photocatalytic activity of TiO(2) films synthesized via the sol-gel process has been measured as a function of UV irradiation time and substrate temperature. Fourier-transform infrared spectroscopy has been used to address the chemical changes in stearic acid and block copolymer Pluronic F127 films deposited on the photocatalytic surface. When the temperature of the photocatalytic substrate was raised above 50 degrees C, the removal of stearic acid from the surface was strongly affected by a process involving evaporation, whereas Pluronic F127 revealed a superior stability. Our study shows that heat enhances the photocatalytic activity, suggesting the importance of an accurate temperature control in photocatalytic efficiency measurements.


Assuntos
Membranas Artificiais , Fotoquímica/métodos , Titânio/química , Titânio/efeitos da radiação , Catálise , Teste de Materiais , Transição de Fase , Temperatura , Raios Ultravioleta
11.
J Nanosci Nanotechnol ; 9(3): 1858-64, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19435050

RESUMO

Two different sol-gel hybrid organic-inorganic films doped with luminescent CdS or PbS quantum dots (QDs) have been successfully synthesized and patterned using nanolithographic techniques. The feasibility of applying X-ray lithography and RIE to pattern hybrid materials doped with highly luminescent nanoparticles has been demonstrated for GPTMS-GeO2 (G-GeO2) and MPTMS-ZrO2 (M-ZrO2) hybrids obtained form 3-glycidoxypropyltrymethoxysilane (GPTMS), methacryloxy-propil-trimethoxysilane (MPTMS), germanium ethoxide and zirconium propoxide. Semiconductor doped film have been obtained by mixing ZrO2-SiO2 or GeO2-SiO2 sol-gel hybrid organic-inorganic matrix solution with CdS or PbS colloidal doping solution to obtain up to 20% molar concentration of QDs inside the films. Patterns consisting of pillars with different aspect ratio have been obtained by X-ray lithography and reactive ion etching (RIE). Structural and optical characterization of films before and after the lithographic process pointed out that both matrices and QDs retain their original properties without been affected by X-rays irradiation and RIE in the conditions here described.

12.
Nanotechnology ; 19(17): 175306, 2008 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-21825670

RESUMO

New epoxy based sol-gel organic inorganic materials, showing lithographic resist-like properties without the addition of any photocatalysts, are presented. To obtain a material sensitive to radiation, specific sol-gel syntheses based on an organically modified alkoxide containing an epoxy ring, 3-glycidoxypropyltrimethoxysilane (GPTMS), have been developed. The synthesis and the patternability of hybrid materials have been obtained controlling the inorganic crosslinking degree and with an almost total absence of organic polymerization. Two examples of directly patternable hybrid films, called GB and GGe, have been synthesized using acidic (GGe) and basic (GB) conditions and obtaining different compositions. After electron beam lithography (EBL) or x-ray synchrotron radiation lithography (XRL) the polymerization of the organic component of the sol-gel film occurs, generating a hardening of the structure after post-exposure baking. The exposed polymerized material becomes insoluble, determining a negative resist-like behaviour of the film: the lithographic process of nanopatterning results from the dissolution of the unexposed areas in proper solvents (developers). Spatial resolution of the order of 200 nm is reported and a contrast of 2.2 is achieved. The novelty of this work is that epoxy based materials, which have enhanced thermomechanical stability with respect to the more usual acrylic based resins, are directly nanopatterned for the first time by electron beam (EB) and/or x-ray beam radiation exposure without the aid of catalysts for polymerization. In contrast to common resists that are sacrificial layers of the fabrication process, direct patternable sol-gel hybrids constitute the final material of the devices. In fact, an example of doping with a light emitting dye is reported together with the achievement of directly patterned structures by EBL and XRL.

13.
J Control Release ; 116(3): 295-303, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17097181

RESUMO

The potential of wet sol-gel derived silica gels as new matrices for the entrapment and sustained release of proteins was investigated. Model proteins, BSA, ribonuclease-A and avidin, with differing molecular weights and/or isoelectric points, were entrapped in two silica polymer formulations having different silica contents (4% and 12% wt/v). The conformational stability of the proteins after entrapment and their release after immersion into physiological conditions were measured. Circular dichroism analysis showed that protein conformation is maintained after entrapment and stability is enhanced. Protein-free formulations were injected intramuscularly into BALB/c mice to monitor the in vivo fate of the matrix, and the results showed that the gel is totally reabsorbed, without any apparent surrounding inflammation process. The time required for matrix bioerosion varied between one to three weeks, depending on its SiO(2) content. Erosion was also measured in vitro and the contribution of erosion and diffusion to the release of the embedded proteins was quantified. These data indicate that wet silica polymers obtained by the sol-gel route are promising matrices for the sustained release of protein drugs.


Assuntos
Portadores de Fármacos/química , Proteínas/química , Dióxido de Silício/química , Animais , Dicroísmo Circular , Preparações de Ação Retardada , Portadores de Fármacos/efeitos adversos , Portadores de Fármacos/farmacocinética , Composição de Medicamentos , Estabilidade de Medicamentos , Feminino , Ponto Isoelétrico , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular , Transição de Fase , Proteínas/efeitos adversos , Proteínas/farmacocinética , Sílica Gel , Dióxido de Silício/efeitos adversos , Dióxido de Silício/farmacocinética , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Solubilidade , Fatores de Tempo , Molhabilidade
14.
Tissue Eng ; 12(12): 3509-23, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17518687

RESUMO

A wide range of biochemical signals promoting cell functions (adhesion, migration, proliferation, and differentiation) and thereby improving the osseointegration process are currently investigated. Unfortunately, their application for the production of bioactive implantable devices is often hampered by their insolubility; instability; and limited availability of a large amount of inexpensive, high-purity samples. An attractive alternative is the use of short peptides carrying the minimum active sequence of the natural factors. Synthetic peptides mapped on fibronectin and vitronectin have been demonstrated to enhance cell adhesion both to polystyrene and acellular bone matrix; in particular, a nonapeptide sequence from human vitronectin works via an osteoblast-specific adhesion mechanism. In this study, we incorporated these peptides into a sol-gel silica dressing applied to coat sand-blasted and acid-attacked titanium samples; measured the kinetic of peptide release; and used titanium disks, coated with a peptide-enriched film, as substrates to determine the peptide concentration that maximizes cell adhesion in vitro. We also evaluated in vivo the capacity of the vitronectin-derived peptide to improve osteogenic activity: histologic analysis revealed markedly improved osteogenic activity around peptide-enriched samples. This article also discusses the role of surface characteristics and the importance of bioactive peptides.


Assuntos
Materiais Revestidos Biocompatíveis , Fibronectinas/metabolismo , Fragmentos de Peptídeos/metabolismo , Dióxido de Silício , Vitronectina/metabolismo , Animais , Células Cultivadas , Materiais Revestidos Biocompatíveis/administração & dosagem , Avaliação Pré-Clínica de Medicamentos , Fibronectinas/administração & dosagem , Fibronectinas/ultraestrutura , Masculino , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/síntese química , Coelhos , Ratos , Ratos Sprague-Dawley , Dióxido de Silício/administração & dosagem , Propriedades de Superfície , Vitronectina/administração & dosagem , Vitronectina/ultraestrutura
15.
J Synchrotron Radiat ; 12(Pt 6): 734-8, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16239741

RESUMO

Two examples of phase transition in self-assembled mesostructured hybrid thin films are reported. The materials have been synthesized using tetraethoxysilane as the silica source hydrolyzed with or without the addition of methyltriethoxysilane. The combined use of transmission electron microscopy, small-angle X-ray scattering and computer simulation has been introduced to achieve a clear identification of the organized phases. A structural study of the self-assembled mesophases as a function of thermal treatment has allowed the overall phase transition to be followed. The initial symmetries of mesophases in as-deposited films have been linked to those observed in samples after thermal treatment. The monodimensional shrinkage of silica films during calcination has induced a phase transition from face-centered orthorhombic to body-centered cubic. In hybrid films, instead, the phase transition has not involved a change in the unit cell but a contraction of the cell parameter normal to the substrate.

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