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Current oral squamous cell carcinoma chemotherapies demonstrate off-target toxicity, which could be reduced by local delivery. Curcumin acts via many cellular targets to give anti-cancer properties; however the bioavailability is hindered by its physicochemical characteristics. The incorporation of curcumin into emulgel systems could be a promising approach for its solubilization and delivery. The aim of this work was to develop emulgel systems containing curcumin for the treatment of oral cancer. The emulgels containing curcumin were prepared with poloxamer 407, acrylic acid derivatives, oil phase (sesame oil or isopropyl myristate). The more stable system was evaluated for mechanical and rheological properties, as well as, the in vitro drug release profile, permeation and cytotoxic potential to oral mucosa models. The flow-throw system evidenced that the formulations could keep 5 min over porcine oral mucosa. Emulgel showed pseudoplastic behavior and a gelation temperature of 33 °C, which ensure their higher consistency. In addition, 70% of the incorporated curcumin was released within 24 h in an in vitro drug release study and could permeate porcine oral mucosa. Monolayers cultures and tissue-engineered models showed the selectivity of the drug and systems for tumor cells. The physicochemical properties, subsequent release and permeation of curcumin to selectivity kill cancer cells could be improved by the incorporation into emulgel systems.

Fish oil (FO) is a natural source of omega-3 fatty acids, with well-established beneficial effects in inflammatory diseases when FO is orally administered. This study investigated the effects of a topically applied FO preparation (FOP) on phenol-induced ear edema and evaluated the percutaneous penetration of FOP in ear tissue. After applying phenol, groups of mice received FOP on the ear. After 1 h, ear tissue was collected to determine the percent inhibition of edema, myeloperoxidase activity, and to perform photoacoustic spectroscopy (PAS). Treatment with FOP did not reduce edema, but reduced myeloperoxidase activity. The FOP decreased the area of bands that characterize inflamed tissue and penetrated into the tissue. These results indicated an inhibitory effect of FOP on leukocyte recruitment in phenol-induced ear edema. These data support the applicability of PAS as a non-destructive method for evaluating the inflammatory response, percutaneous penetration and antiinflammatory activity of compounds.

We present a detailed spectroscopic study of photoluminescence in calcium aluminosilicate glasses doped with different concentrations of Pr 3 + (0.2, 0.5, 1.0 and 2.0 wt%). Optical transitions for the levels H 4 3 → P 0 , 1 , 2 3 ; I 6 1 ; D 2 1 ; G 4 1 ; 3 F 2 , 3 , 4 and H 6 3 have been observed using UV–Vis–NIR spectroscopy at room temperature. Emissions from levels P 0 3 and D 2 1 were detected and curves deviate from exponential behavior. Upconversion to UV was also observed when the samples were excited in the 3 P j level, populating 4f5d upper level — via energy transfer upconversion and/or excited state absorption — which decays emitting UV light. In addition, the unusual variation of the peak intensities of transitions P 0 3 → F 2 3 and P 0 3 → F 4 3 suggests they are hypersensitive, although the 3 P 0 → 3 F 4 electronic transition does not entirely obey all the classic selection rules.

Eu-doped calcium aluminosilicate glass and glass-ceramic were synthesized and studied by site-selective spectroscopy. Using both broadband excitation and fluorescence line narrowing techniques, the D 0 5 → F 1 7 emission transition was studied under resonant excitation at different wavelengths within the F 0 7 → D 0 5 band. In order to explore the local structure of the systems, crystal-field analysis was applied assuming C 2 v site symmetry. Moreover, from the emission spectra of glass and glass-ceramic systems, Judd-Ofelt parameters Ω t (t = 2, 4) were considered. Transition probability (A), stimulated emission cross-section ( σ ), radiative lifetime ( τ R ) and branching ratios ( β ) due to the transition D 0 5 → F J 7 (J = 1, 2, 3 and 4) of Eu 3 + ions were evaluated in different local fields and their relative variations were discussed. The crystallization process, which converted the glass into glass-ceramic, promoted an important enhancement in the quantum efficiency, which was improved from 45% to 60%.

Natural or synthetic biomaterials are increasingly being used to support bone tissue repair or substitution. The combination of natural calcium phosphates with biocompatible alloys is an important route towards the development of new biomaterials with bioperformance and mechanical responses to mimic those of human bones. This article evaluated the structural, physical, mechanical and biological properties of a new mechanical improved nanocomposite elaborated by association of fish biphasic calcium phosphate (BCP) and niobium pentoxide (Nb

SUMMARY Objectives: This study evaluated effects of Bioglass 45S5 (BG) and Biosilicate (BS) remineralization on the chemical composition and bond strength of control dentin (CD) and bleached dentin (BD) surfaces. Methods and Materials: Dentin bleaching treatment was performed using the walking bleaching technique with 0.01 g of sodium perborate and 0.5 mL of 3% hydrogen peroxide for 14 days. Remineralization treatment was carried out by rubbing a remineralization solution (0.015 g of BG or BS diluted in 1.35 mL of distilled water) on the etched dentin surface for 30 seconds. Micro-Raman spectroscopy (MRS) was used to quantitatively analyze the mineral matrix ratios of CD and BD (n=5) after remineralization treatment with BG and BS over 15 days of incubation in artificial saliva. The CD and BD discs (n=10) with and without remineralization treatment with BG and BS were restored using a two-step etch-and-rinse adhesive system (Optibond S, Kerr) and five layers of 1-mm-thick composite resin (Filtek Z250, 3M ESPE). The restored dentin discs were sectioned into nine bonded beams with cross-sectional areas of approximately 0.9 mm2 and tested for microtensile bond strength (μTBS). The dentin surface of one fractured beam per tooth was submitted to MRS to characterize the physicochemical composition (n=10) at the interface. The data were analyzed using one-way analysis of variance and the Tukey-Kramer post hoc test (p Results: MRS bioactive analyses revealed that both BG and BS promoted increased mineral matrix ratios in the CD and BD. Significantly higher μTBS values were found after CD treatment with BG (CD: 57 MPa±11; CD-BG: 78 MPa±15) and when BG and BS were applied to the BD (BD: 42 MPa±5; BD-BG: 71 MPa±14; BD-BS: 64 MPa±11) (p Conclusion: Remineralization of BD is an effective therapy to restore damage caused by dentin bleaching and acid conditioning. This approach not only increases dentin mineral compounds but also improves dentin's ability to interact chemically with the adhesive system.

Photodynamic therapy (PDT) may have topical indications. In those cases it is important for a topical photosensitizer to penetrate into the tissue to which it has been applied. This study aimed to compare the penetration of two different concentrations of erythrosine into intact and in vitro decayed dentin samples.This in vitro study evaluated erythrosine (0.3 and 5%) penetration into sound (intact) and decayed dentin. A total of 11 dentin discs were prepared and divided into two equal halves, in order to keep one half sound while the other half was submitted to sterilization and an in vitro demineralization model for 5 days. Before erythrosine application, the organic and inorganic composition of all samples was evaluated by Fourier Transform Raman spectroscopy, and after erythrosine application for 30 min, the penetration depth was determined by Photoacoustic spectroscopy technique.The results indicated that 0.3% erythrosine showed a higher penetration depth into sound dentin (p = 0.002); and 5% erythrosine higher penetration into decayed dentin (p 0.001). However considering clinical parameters, no statistically significant difference was found between any of the conditions tested.Erythrosine demonstrated ability to penetrate into dentin, irrespective of sound or decayed condition. Photoacoustic spectroscopy can be considered a method for estimating the penetration into hard tissues, and in conjunction with Raman spectroscopy, these are effective methods for evaluating the spectral response of dentin. Considering that erythrosine is capable of penetrating into decayed dentin, clinical trials are needed to test the effectiveness of this photosensitizer in Photodynamic therapy and Antimicrobial Photodynamic therapy.

Laser induced wavefront distortion is critical for designing and evaluation of optical components for high-power laser and can affect performance and stability of optical systems. The analysis of this effect involves a complex thermoelastic problem only solved in simplified conditions such as the plane-stress or plane-strain configurations. For more realistic descriptions, numerical solutions are required, although recent advances allowed for a unified model to describe the optical path change, regardless of the sample thickness, assuming a sample of infinite radius. In this work, we extend this result for the case of a thick-disk sample by solving the set of differential equations governing the thermoelastic response for the finite radius configuration. These results could represent a significant contribution for designing and characterization of laser systems with potential application in many photothermal methods for material characterization.

Efficient white-emitting phosphor-in-glass (PiG) was successfully synthesized by synergistic complexation of Ce3+-doped YAG phosphor and Eu 3 + -doped sodium calcium silicate glass. The crystalline phosphor was obtained via sol-gel route using polyvinyl alcohol (PVA), whereas glasses were prepared by melting-quenching method. Rare-earth ions were successfully incorporated into the YAG and glass host lattices without changing their original structures. Through adjusting the Eu3+-doped glass and Ce3+:YAG phosphorus contents in the PiG, it was possible to optimize the chromaticity emission from yellow-green to orange-red in CIE 1931 diagram. Combination of a violet LED and samples emissions, allowed to achieve the chromaticity parameters closer to an ideal white light source [CIE-(0.33, 0.33); CCT 5000K]. Moreover, adjusting the luminescence intensity ratio between the LED and the PiG emission provides a tuning route for smart white light devices.

The challenge of modifying the solar spectrum intensifies efforts in the pursuit of enhanced materials and optical systems. In this work, we present novel and efficient near infrared-emitting Eu2+ and Nd3+ co-doped sodium calcium silicate glasses. Optical absorption, excitation spectra, emission decay time, were measured and discussed as a function of Nd2O3 content. Laser power-dependent emission intensity was used to evaluate the transfer mechanism, and an energy level diagram was proposed. For the sample doped with optimized neodymium content, energy transfer efficiency reached 70%. For co-doped samples, the excitation spectrum was broadly intense and perfectly overlapped with the solar spectrum in the NUV region. Therefore, NUV/Visible can be efficiently converted into NIR, precisely where the C-Si response is maximal, through the Eu2+→Nd3+ pathway. This work’s outcomes made the focused materials worthy for solar cell applications, optimizing energy conversion lost by thermalization, into useful energy.

Thermoresponsive micellar gels of Pluronic F127® and Carbopol C934P® blends have recently received interest as a dermatological platform for photosensitizer delivery in infected wounds. In this context, Rose Bengal B is an appropriate photosensitizer for minimizing bacteria strains that cause secondary infections of various wound groups. In this work, we proposed a micellar platform containing Rose Bengal B, ainming to treat dermatological wounds. The easy administration, on-site retention, and sustained photosensitizer delivery performance are some of the benefits that the system can combine. Sol-gel transition temperature, mechanic, rheologic, permeability properties, and bioadhesion analyses of formulation in ex vivo systems were examinated, using porcine ear skin. The formulates have shown appropriate gelling properties for topical treatments, with phase transition around 25 °C. Mechanic and rheologic analyses identified pseudoplastic behavior and thixotropy properties. This information reveals reductions in viscosity with shear stress, allowing easier mixing, pumping, bottling, and packing. Besides, these analyses showed the systems' viscoelasticity, a determining condition for an adequate formulation performance after its administration. In addition to all these benefits, formulates showed bioadhesive properties and a considerable skin permeation capacity of micelles that contained Rose Bengal B.

Four alternative fuels (AF) were blended with ultralow sulfur diesel (ULSD) at five different proportions (10, 20, 30, 50, and 100 vol % AF) to create 20 binary mixtures in this work. Two renewable jet AFs and two renewable diesel AFs were investigated. Interactions between the components in the mixtures were analyzed by means of spectroscopy (Raman, near-infrared), thermophysical (thermal diffusivity, thermo-optic coefficient), and physical (density) techniques. Correlations among the data were investigated using principal component analysis and partial least-squares regression. Trends in Raman intensities and band positions as well as thermophysical properties showed that the AF/ULSD blends resembled two-component mixtures despite the known complexities of the constituents. Specifically, spectra combined according to the percentages of the components in each mixture; thermophysical and physical properties exhibited similar behavior. The spectra showed strong correlations with all three physical properties, creating the possibility for predicting the properties of similar AF/ULSD mixtures. These properties are governed by the chemical compositions of the fuels.

Nowadays the increase in life expectancy of the population has made diseases related to bone structure a worldwide public health problem. In the field of bone regeneration, calcium phosphate-based ceramics hold the greatest promise of efficiency and hydroxyapatite presents itself as reference material because, in addition to presenting a chemical composition similar to the mineral composition of bone tissue, it is biocompatible, osteoconductive, and osteoinductive, and can be reinforced with other more resistant materials, such as titanium, aluminum, zirconia, and niobium. In this scenario, fish bones represent an abundant and low-cost natural source of hydroxyapatite that is promising for the production of more resistant devices for bone regeneration. The objective of this work was to evaluate the physicochemical properties of the natural HAp, extracted from bones of Nile tilapia (Oreochromis niloticus) and of the HAp-Nb-1080 composite. Besides, the bioperformance of scaffoldings of both materials was evaluated in terms of bone regeneration. The granulometric, XRD, ATR-FTIR, micro-Raman, micro-CT and, SEM analyzes were performed to HAp and HAp-Nb-1080 powders characterization. The bone regeneration was studied 15, 30, and 45 days after implantation of 8 mm scaffolds in critical-size defects in rat calvaria. The results showed that fishbone HAp presented the molar ratio (Ca/P) of 1.66. The average particle sizes of the HAp and HAp-Nb-1080 powders were in the order of 1150 and 750 nm, respectively. After sintering the composite, three new crystalline phases were formed: β-tricalcium phosphate Ca3(PO4)2 (34%), fersmite (CaNb2O6) (33.5%), and phosphorus niobium oxide (PNb9O25) (32.6%), confirmed by ATR-FTIR, and micro-Raman analyzes. The scaffolds porosities were 57% to HAp and 59% to HAp-Nb-1080 composite. SEM results showed the presence of opened macro and microporosity as well as porous interconnectivity. The histological study showed bone formation inside porous in all analyzed time interval after the implantation. In this study, we demonstrated that the HAp-Nb-1080 composite presented physicochemical characteristics that satisfy the requirements for a mechanically reinforced biomaterial for bone regeneration.

The photocatalysts of rGO supported on TiO2 were obtained in situ by a sequence of an improved Hummers' method and an eco-friendly hydrothermal procedure. The XRD diffractograms did not present the signals corresponding with the rGO. However, they were detected in micro-Raman because of the characterized signals of D and G bands observed. From TEM, the rGO sheets were visualized covering the surface of TiO2. The photocatalytic experiments were conducted in a real-time monitoring UV-LED mini-reactor (3.0 mL, 5 W and λmax of 365 nm) with small aliquots of sample and catalysts. The catalysts were employed to photodegrade the organic dyes: methylene blue (MB) and tartrazine (TAR), as models or recalcitrant pollutants. The photocatalytic kinetic curves were described by first order kinetic model. Both dyes were completely degraded by all photocatalysts with up to 250 min of irradiation. All supported rGOTiO2 catalysts presented faster kinetics than the TiO2. For MB degradation, 1rGOTiO2 was 6× faster and for TAR degradation 1rGOTiO2 was 3× faster than TiO2. The main action of 1rGOTiO2 was attributed to the better charge transfer by the higher sp2 carbon domains. This result indicates that rGOTiO2 are promising photocatalysts for the degradation of recalcitrant organic pollutants.

Dermatological formulations can enable a more efficient therapy by directly delivering the active ingredient to the action site. Photodynamic therapy is a promising technique to eliminate the microorganism in wounds. The present work aims to obtention a dermatological bioadhesive and stimuli-responsive platform that efficiently solubilizes aluminum phthalocyanine hydroxide (AlPcOH) photosensitizer. A better formulation for dermatological application was obtained after evaluation of the formulation polymeric composition and mechanical characterization. Ex-vivo permeation and complete rheological assays were carried out. The photodynamic potential of AlPcOH was evaluated quantitatively and qualitatively. AlPcOH was shown to be incorporated mostly in monomeric form when subjected to the solid dispersion method. Satisfactory results were achieved for the formulation composed of 0.05, 20, and 0.20 % w/w of AlPcOH, F127 and Carbopol. This formulation was easily administered and presented adequate retention at the application site. Furthermore, the system showed a gelation temperature of 29.1 °C, ensuring the preparation, filling, and administration in the bodýs temperature. The nanostructured thermo-responsive platform promoted AlPcOH skin permeation effects and demonstrated a high capacity to generate reactive oxygen species (ФΔ1O2 for AlPcOH of 0.68 in ethanol). All the information provided in this study supports the potential of the AlPcOH-containing platform designed to treat wounds aggravated by microbial infections. It suggests future in vitro and in vivo applications of the platform developed.

Paracoccidioides brasiliensis (Pb) can disseminate through the lymphatic and hematogenic pathways. As a result the spleen and other lymphoid organs are targets of paracoccidioidomycosis. There are few studies describing this disease in the spleen and more detailed descriptions are required. This study combines Histopathology and Fourier Transform Raman Spectroscopy (FT-Raman) methods to study spleen infected by Pb. The Swiss mice were euthanized after 1, 2, 4 and 8 weeks of infection with Pb, and their spleens were removed for ex vivo analyzes. Histopathological evaluation revealed that the red pulp was the area most affected, presenting the highest concentration of yeasts, inflammatory cells and cells in apoptosis, with no observation of typical granuloma formation. The main physical-chemical changes were detected in the spectral ranges between 1730-1590 cm-1 and 1390-1280 cm-1 attributed to amide I and vibrational deformation mode of CH3 and CH2 molecules, respectively. The amide I was correlated to total protein content and CH3 and CH2 molecules to collagen of the spleen. The association between histological and physical-chemical methods enabled detection of several alterations in the spleen, including apoptosis, contributing to a better understanding of paracoccidioidomycosis, a tropical neglected disease.

In this work, laser-induced Thermal Lens Temperature Scanning technique (TL-TS) is applied to evaluate oxidative stability and time of transesterification during biodiesel synthesis. Samples collected at different time intervals during the transesterification process of sunflower (SF) and soybean (SB) oils were submitted to fast oxidation through temperature scanning (between 22 and 190 °C), and simultaneously measured with the TL-TS technique. Temperature dependence of Thermal Lens effect amplitude showed the occurrence of oxidation, with the onset (Tonset) changing with the transesterification stages from 149 to 169 °C for sunflower and from 120 to 142 °C for soybean samples. The characteristic evolution of Tonset with reaction duration was estimated to be ∼7 min for sunflower and ∼10 min for soybean samples. The thermal diffusivity values were shown to be sensitive to rapid changes at transition temperatures, which could be related to molecular ruptures. Additional measurements were performed with DSC, TG and FTIR, to validate the information obtained by the TL-TS technique. In conclusion, the results showed the TL-TS technique as a promising tool for oxidative stability evaluation and determination of both chosen working temperature and minimal time interval for the solution to reach an optimized transesterification stage, thus contributing for reduction of costs, quality control and consequently for certification of biodiesel fuels.

Biodiesel susceptibility to oxidation is one of the major problems concerning its use as an alternative to diesel fuel. Although well-characterized, the oxidation process cannot be completely prevented since it can be affected by a large number of factors, such as fuel composition, storage conditions, contaminants, temperature, and the presence of air and light. In this work, we propose Fourier transform infrared spectroscopy (FTIR) in association with principal components analysis (PCA) and hierarchical cluster analysis (HCA) as a method for monitoring the extent of oxidation degree of biodiesel in the low rate phase, before the end of the induction period, in which the changes in the physical properties such as viscosity, mass density, and chain composition of the sample remain almost undetectable. A detailed investigation of thermo-oxidation of biodiesel is reported for a mixture of 50/50 (%) of soybean oil and animal fat biodiesels. The biodiesel degradation was accelerated when maintaining the temper...

SUMMARY The purpose of this study was to evaluate the chemical bonds of a self-etch 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) adhesive to natural noncarious cervical lesions (NCCLs) and compare them with those occurring in sclerotic dentin in artificially prepared defects (APDs). Four human teeth with natural NCCLs on the buccal surface were selected. Artificial defects matching the natural lesions were prepared on the lingual surface of the same teeth serving as control. Micro-Raman (MR) spectroscopy was used to quantify mineral content in natural NCCLs and in APDs. Fourier transform infrared-photoacoustic spectroscopy (FTIR-PAS) readouts were taken before and after adhesive application to analyze the protein matrix/mineral (M:M) ratio and chemical interactions between 10-MDP adhesive and dentin. The MR and FTIR-PAS spectra collected from natural NCCLs demonstrated a larger area of the band (961 cm−1, PO4) and lower M:M ratio, respectively, characterizing a hypermineralized dentin, compared with APDs. FTIR-PAS demonstrated emergence of a peak (1179 cm−1, P=O) in spectra after adhesive treatment, demonstrating a more intense chemical interaction in natural NCCLs. The results demonstrated that chemical bonding of 10-MDP adhesive to natural NCCLs is more intense, due to the hypermineralized surface, and suggest that it is unnecessary to remove the hypermineralized layer with burs, as this may decrease the chemical bonding potential of 10-MDP.

Bioactive ferroelectric composites based on polyvinylidene fluoride, hydroxyapatite and β-tricalcium phosphate have been synthesized and their structural, microstructural, bioactive, and ferroelectric properties are characterized. Structural and FTIR investigations showed the presence of the polar polyvinylidene fluoride (β2) phase, while ferroelectric characterizations revealed remnant polarizations and coercive field, around 0.04 μC/cm2 and 28 kV/cm, respectively, for these biocompatible samples. Structural and microstructural analysis of samples previously immersed in simulated body fluid for 7 days revealed a large apatite phase growth (1.45 μm) on the composites' surfaces as a strong indication of their elevated bioactivity and potentialities for bone tissue engineering.

Made available in DSpace on 2018-11-26T17:16:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundacao de Apoio ao Desenvolvimento do Ensino, Ciencia e Tecnologia do Estado de Mato Grosso do Sul (FUNDECT) In this work, the combination of three different thermal lens spectroscopic methodologies was used to better determine the fluorescence quantum yield and to observe the concentration quenching in Yb3+-doped binary tellurite glasses (in mol%, 80TeO(2) 20Li(2)O and 80TeO(2) - 20WO(3)). The samples were synthesized by the conventional melt-quenching method and then studied using optical spectroscopy and thermal lens spectroscopy (Us). These characterizations enabled investigation of the radiative and nonradiative processes involved in the ytterbium doped systems. High fluorescence quantum yield was obtained for low Yb3+ doping (>90%), and in both glasses the Yb3+ presented concentration quenching mainly caused by impurities, host-ion interaction and OH- vibrations. The observations suggested that there is a possibility of doping the glasses with higher Yb concentration (>1.6 x 1021 ions/cm(3)) with low reduction of the quantum yield. (C) 2016 Elsevier B.V. All rights reserved. Univ Estadual Mato Grosso do Sul, Grp Espectroscopia Opt & Fototerm, Programa Posgrad Recursos Nat, CP 351, Dourados, MS, Brazil Univ Estadual Paulista, Dept Fis & Quim, Av Brasil 56, BR-15385000 Ilha Solteira, SP, Brazil Fundacao Univ Fed Grande Dourados, Fac Ciencias Exatas & Tecnol, Dourados, MS, Brazil Univ Estadual Maringa, Dept Fis, Av Colombo 5790, BR-87020900 Maringa, PR, Brazil Univ Sao Paulo, Inst Fis Sao Carlos, CP 369, BR-13560970 Sao Carlos, SP, Brazil Univ Estadual Paulista, Dept Fis & Quim, Av Brasil 56, BR-15385000 Ilha Solteira, SP, Brazil FAPESP: 2013/19747-9 Fundacao de Apoio ao Desenvolvimento do Ensino, Ciencia e Tecnologia do Estado de Mato Grosso do Sul (FUNDECT): 59/300.031/2015 Fundacao de Apoio ao Desenvolvimento do Ensino, Ciencia e Tecnologia do Estado de Mato Grosso do Sul (FUNDECT): 23/200.735/2014

Poincianella pluviosa has already been described as capable of healing skin wounds. In an attempt to prolong contact of the drug with the wound, it was proposed in this study to evaluate wound healing using a crude extract (CE) of P. pluviosa incorporated in carboxymethylcellulose polymer films. The chromatographic profile of the semipurified fraction of P. pluviosa was evaluated by ultra-high performance liquid chromatography (UHPLC), confirming the compounds gallic acid, geraniin, and ellagic acid. The films were evaluated for their physical and mechanical properties, water vapor permeability, moisture absorption capacity, and FTIR spectroscopy. For in vivo experiments, wounds were made on the back of rats and treated daily for 4, 7, 10, or 14 days with film containing CE or control film. At the end of each period, skin permeation analysis and histological analysis were made using re-epithelialisation, cell proliferation, and collagen formation. Statistical significance was determined by GraphPad Prism using t test and Mann-Whitney test. Anti-staphylococcal activity was evaluated with standard strains of Staphylococcus aureus, methicillin-resistant, and coagulase negative. It was demonstrated that the presence of CE in the films increased the capacity to absorb water and decreased resistance and permeability. The CE of the film permeated the skin, reaching the dermis and was able to influence re-epithelisation, cell proliferation, and collagen formation. Satisfactory results were observed against S. aureus strains, particularly coagulase negative. Films with CE of P. pluviosa can be an alternative in the wound healing, protecting against opportunistic infections and giving comfort to the patient.

Mucoadhesive nanostructured systems comprising poloxamer 407 and Carbopol 974P® have already demonstrated good mucoadhesion, as well as improved mechanical and rheological properties. Curcumin displays excellent biological activity, mainly in oral squamous cancer; however, its physicochemical characteristics hinder its application. Therefore, the aim of this study was to develop nanostructured formulations containing curcumin for oral cancer therapy. The photophysical interactions between curcumin and the formulations were elucidated by incorporation kinetics and location studies. They revealed that the drug was quickly incorporated and located in the hydrophobic portion of nanometer-sized polymeric micelles. Moreover, the systems displayed plastic behavior with rheopexy characteristics at 37 °C, viscoelastic properties and a gelation temperature of 36 °C, which ensures increased retention after application in the oral cavity. The mucoadhesion results confirmed the previous findings with the nanostructured systems showing a residence time of 20 min in porcine oral mucosa under flow system conditions. Curcumin was released after 8 h and could permeate through the porcine oral mucosa. Cytotoxicity testing revealed that the formulations were selective to cancer cells over healthy cells. Therefore, these systems could improve the physicochemical characteristics of curcumin by providing improved release and permeation, while selectivity targeting cancer cells.

The thermal-wave resonant cavity (TWRC) technique has been used for thermal diffusivity measurements by many researchers. This study aims to reduce the uncertainty associated with TWRC signal processing (curve fitting) by means of numerical simulation and experimental verification. Simulations show that the plot of signal amplitude versus cavity length can be fitted to a simplified model reported previously when the initial fitting position is at least twice the thermal-wave diffusion length (2 μg), and that the uncertainty caused by different end positions is negligible in the range of 6–10 μg. Upon consideration of the simulation results, signal-to-noise ratio, and clearly defined amplitude curve shape, fitting ranges of about 2.2–8.0 μg and 2.2–8.7 μg were chosen for the experimental data. Thermal diffusivity values (1.438 ± 0.001) × 10−7 and (1.436 ± 0.001) × 10−7 m2 s−1, respectively, were obtained for distilled water, in excellent agreement with the accepted literature value. The ratio of standard deviation to the mean value is smaller than 0.07%, one order of magnitude lower than typical results reported in the literature. Similar simulation results were obtained for air and methanol as intra-cavity samples.

The small energy difference between the fundamental level and the first opposite parity configuration of Pr3+-doped hosts is particularly challenging for the characterization of radiative transitions using the Judd-Ofelt theory, although modified versions of the theory have been proposed in the past for the investigation of praseodymium doped materials. Here, we present a detailed spectroscopic investigation on two sets of calcium aluminosilicate glasses, with 34 wt% of SiO2 (CAS) and with 7 wt% of SiO2 (LSCAS), doped with different concentrations of Pr3+ (0.5, 1.0 and 2.0 wt%). We use the standard Judd-Ofelt theory to characterize the glasses and the results and derived spectroscopic quantities — such as transition probabilities, radiative lifetimes and branching ratios — are compared to results obtained by the modified Judd-Ofelt theories. The analysis showed that the modified theories could lead to smaller values of root mean square deviations. However, a better agreement between experimental data and the standard theory was achieved when the derived spectroscopic quantities are taken into account. Moreover, the branching ratios of the P 0 3 → H 4 3 and D 2 1 → H 4 3 transitions were over 60% for both glass hosts, suggesting its potential use as solid-state laser devices.

Aim: To evaluate and characterize the etiopathogenesis of the fusarial onychomycosis in an ex vivo study through fragments of sterile human nail, without the addition of any nutritional source. Materials & methods: The infection and invasion of Fusarium oxysporum in the nail were evaluated by scanning electron microscopy (SEM), CFU, matrix, histopathology and Fourier Transform Infrared Spectrometer coupled to an equipment with diamond accessory (FTIR-ATR). Results: F. oxysporum infected and invaded across the nail, regardless of application face. However, the dorsal nail surface was the strongest barrier, while the ventral was more vulnerable to infection and invasion process. The fungal–nail interaction resulted in the formation of a dense biofilm. Conclusion: F. oxysporum infect and invade the healthy human nail, resulting in biofilm formation. Therefore, F. oxysporum is likely a primary onychomycosis agent.

The constant demand to accurately measure the temperature sheds light on luminescent materials that have dependence on their thermodynamic quantities. Several materials have been applied as sensors to measure temperature for different applications, however, very few showed high precision and sensitivity. This work reports the Eu 2 + /Eu 3 + -doped low-silica calcium aluminosilicate glass as a potential candidate for high sensitive ratiometric thermometer. The glass was analyzed close to the physiological temperature range, between 288.15 – 333.15 K. Since this glassy matrix provides the presence of two europium valences, two different approaches are presented. The first takes into account the temperature dependence of 5 D 0 → 7 F 4 emission for two different excitation wavelengths, and the second one is based on the interplay between Eu 2 + and Eu 3 + emissions. Both ratiometric approaches presented high reproducibility and relative sensitivity values, from 1.2 to 1.6 %/K and from 0.75 to 0.95 %/K, for the first and second approach, respectively.

We report on the thermoelastic properties of Ni 2 MnGa shape-memory alloys across the martensitic to austenitic phase transition using the time-resolved pump–probe photothermal mirror technique. Quantitative information on the thermo-mechanical characteristics of the sample are obtained and compared to specific heat measurements and differential scanning calorimetry (DSC) analysis. The thermal diffusivity varied remarkably within the martensitic–austenitic transition range. Both the amplitude signal and the thermal diffusivity present, in addition to the strong martensite to austenite phase transition, a clear evidence of a subtle second-order type phase transition close to 80 ° C. This magnetic transition is also observed in the calorimetric analysis. The transformation temperatures suggest the non-stoichiometric composition of sample, which is also revealed by non-symmetrical shapes of DSC peaks. The possible variation of the local chemical composition could be a result of gallium loss during the sample preparation or local inhomogeneity in the martensitic transformation.

International audience; In this report, Ti3+, 4+/Eu2+, 3+ co-doped OH− free low silica calcium aluminosilicate glasses (LSCAS) were synthesized and their optical properties investigated aiming applications as phosphors for white light generation. This research explores the possibility of combining the broad emission bands in the visible of these glasses co-doped with Ti3+,4+/Eu2+ ions with those in the red emitted by Eu3+, in addition to the high luminescence quantum yield they present. The excitation and emission results show that exciting the samples at 300 nm, a broad emission band is generated, embracing very well the visible region. The emission spectra were analyzed by (x-y) CIE-1931 chromaticity diagram and the color rendering index (CRI) presented Ra values up to 80, with the correlate color temperature (CCT) varying from 4995 to 6609 K. The luminescence quantum yield determined by Thermal Lens Spectroscopy showed values of 38 and 42% for the samples with (in wt%) 0.1Eu2O3-2.0TiO2 and 0.5Eu2O3-2.0TiO2, respectively. Finally, the energy transfer processes between these luminescent ions were discussed, highlighting the potential of the Eu–Ti LSCAS glasses as candidates for the development of devices for white light generation.

It now well known in laser materials, that a refractive index change appears when the active ions are pumped from ground to excited state due to the polarizability difference between ground and excited states (metastable). In this paper this effect was investigated in Tb3+ doped glasses: calcium alumino phosphate (CAP), low-silica calcium aluminosilicate (LSCAS) and calcium aluminosilicate (CAS). The measurements were performed using the time resolved Z-scan technique, with an Ar+ laser at 488 nm, close to the resonance of 7F6→5D4 absorption line, where 5D4 is a metastable state. We obtained for low-silica calcium aluminosilicate glass Δαp~10−24 cm3 which is the highest value ever reported for a RE doped material.

Thermophysical measurements and Raman spectroscopy were utilized to investigate 17 hydrocarbon distillates derived from Canadian oil sands in this work. Thermal lens and optical interferometer techniques were used to determine the thermal diffusivity ( D ) and temperature coefficient of the refractive index ( dn/dT ), respectively. It was found that D and dn/dT are closely correlated with the cetane numbers, distillation temperatures, monocyclic aromatics contents, and kinematic viscosities of the fuels. Raman spectra yielded information on the chemical compositions of the distillates, with aromatic contents proving to be particularly relevant. Multivariate analysis elucidated the relationships among the samples, their properties according to ASTM analyses, and the influence of composition on D and dn/dT .

Succinoglycans are heteropolysaccharides synthesized by bacteria. It possesses thickening and texturizing properties, making it useful in a number of applications in food, pharmaceutical and chemical industries. Agrobacterium radiobacter NBRC 12665 cells were immobilized in the loofa sponge matrix and used to produce succinoglycan. Production of the biopolymer using the substrates sugar cane molasses, sucrose, glucose and lactose at concentrations of 2.5%, 5.0% and 7.5% for eight days was analyzed. The best results were obtained using sugar cane molasses (14.0 g/L) and lactose (12 g/L) at 7.5% with immobilized cells. Under optimum conditions, it was possible to re-use the matrix to produce succinoglycan in five consecutive eight day operating cycles. Scanning electron microscopy and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the immobilization of the microorganism in the loofa sponge. FTIR of the biopolymer revealed the presence of residues of carbohydrate and carboxylic groups. The use of mixed ions exchange resin for removal of the succinoglycan pigments from molasses resulted in a depigmentation of 74% in the color of the biopolymer and 65% in its turbidity. Succinoglycans obtained from lactose and sugar cane molasses exhibited molecular weights of 2.734 y 106 g/mol and 2.326 y 106 g/mol, respectively. Rheological analysis of the succinoglycans in terms of concentration (0.5⿿2.0%), temperature (5⿿75 °C) and pH (2.5⿿10.0) revealed non-Newtonian and shear thinning behavior of the biopolymer. The technique of immobilization in loofa sponge and use of sugar cane molasses as a low cost carbon source produced significant and effective results for the industrial production of succinoglycan.

The network structure pressure dependence of a modified soda lime silicate glass, containing CaF2 and lower SiO2 content, was investigated by micro-Raman spectroscopy. The glass structure was first analyzed under normal pressure conditions in terms of network depolymerization, by comparing with commercial soda lime glass. Using calculation of non-bridging oxygens per tetrahedron (NBO/T), it was found that while commercial soda lime glasses have Q4 and Q3 units, the studied glass system presents a depolymerized structure and it is composed, on average, of Qn with n = 3 and 2. Changes due to high hydrostatic pressure were evaluated by using a diamond anvil cell up to 19 GPa. Raman scattering was used to calculate Si–O–Si angular population according to the network central force, which showed a progressive angle closure with pressure. The Raman spectrum of recovered sample, after compression/decompression cycle, showed negligible changes, suggesting that initial amorphous phase of modified glass is highly stable. The glass showed very high incompressibility, compared to aluminates, silicates, lanthanum borogermanate, or even regular soda lime glasses, suggesting that its bulk modulus is relative high. Polymerized glasses have great space vacancies within the network structure, on the contrary it was observed that the studied glass presents a densely packed structure reflecting on high incompressibility, which decreased the magnitude of permanent densification.

We demonstrate the Soret effect in a lyotropic liquid crystal at different temperatures across the isotropic phase detected by the time-resolved thermal lens technique. We investigate thermo-optical and mass diffusion properties of the sample and present quantitative characterization of Soret, mass and thermal diffusion coefficients. The results reveal that the temperature gradient induced in the experiments causes the migration of micelles from hotter to colder regions in the sample. The increase of the mass diffusion coefficient with temperature is related to the decrease of the radius of the micelles in the solution.

We demonstrate the influence of edge effects on the photothermal-induced phase shift measured by a homodyne quadrature laser interferometer and compare the experiments with rigorous theoretical descriptions of thermoelastic surface displacement of metals. The finite geometry of the samples is crucial in determining how the temperature is distributed across the material and how this affects the interferometer phase shift measurements. The optical path change due to the surface thermoelastic deformation and thermal lens in the surrounding air is decoded from the interferometric signal using analytical and numerical tools. The boundary/edge effects are found to be relevant to properly describe the interferometric signals. The tools developed in this study provide a framework for the study of finite size effects in heat transport in opaque materials and are applicable to describe not only the phase shift sensed by the interferometer but also to contribute to the photothermal-based technologies employing similar detection mechanisms. Prikažemo vpliv robnih učinkov na fototermalno inducirani fazni premik, ki ga merimo s homodinskim kvadraturnim laserskim interferometrom in poskuse primerjamo z eksaktnimi teoretičnimi opisi termoelastičnih površinskih premikov kovin. Končna geometrija vzorcev je ključnega pomena pri določanju, kako se temperatura porazdeli po materialu in kako to vpliva na merjenje faznega premika interferometra. Razliko optične poti zaradi površinske termoelastične deformacije in termalne leče v okoliškem zraku dekodiramo iz interferometričnega signala s pomočjo analitičnih in numeričnih orodij. Mejni/robni učinki so pomembni za pravilen opis interferometričnih signalov. Orodja, razvita v tej študiji, nudijo okvir za preučevanje učinkov zaradi končnih dimenzij pri prenosu toplote v neprozornih materialih in niso uporabna le za opisovanje faznega premika, ki ga zazna interferometer, temveč prispevajo tudi k fototermalnim tehnologijam, ki uporabljajo podobne mehanizme zaznavanja.

The secondary metabolites produced by Fusarium can cause disease and death when consumed and produce biological responses even in the absence of the microorganism. The IL-6, TNF-α and TGF-β1 cytokines immune reactivity was associated with histopathological and physico-chemical changes in skin of immune competent rats after administration of Fusarium oxysporum crude extract. Rats were intradermally injected with 50 μl of 0.5 mg/ml crude extract and were euthanized at 3, 6, 12 and 24 h after injection. The inflammatory response was quantified by enzyme myeloperoxidase activity and by immunohistochemical method to detect the IL-6, TNF-α and TGF-β1. Physico-chemical analysis was performed using FT-Raman Spectroscopy. The inflammatory response was most intense at 6 and 12 h after crude extract administration and the most significant histopathological changes were observed in the dermis. Myeloperoxidase activity was intense from 3 to 24 h after injection. The immunostaining of pro-inflammatory cytokines IL-6 and TNF-α peaked at 6 h. Immunostaining for TGF-β1 was highest at 12 and 24 h. FT-Raman spectral analysis showed both, the most intense Fusarium interaction with the skin at 6 h, as revealed by the changes in the stretching of –CH bands (3100–2800 cm−1) in the dermis, and skin recovery trending after 12 h after crude extract injection. The results showed that secondary metabolites stimulated histopathologic changes and inflammatory responses even in the absence of the fungus, increasing myeloperoxidase activity and pro-inflammatory cytokine expression besides promoting physico-chemical changes.

Microsponges (MS) have shown great potential for the incorporation of relatively higher amounts of drugs. This is due to the presence of both surface pores and interconnected channels that provide a greater contact area for the absorption of active agents. However, the use of MS for carrying hydrophobic drugs is limited because the preparation methodology can totally remove hydrophilic drugs. Therefore, this work aimed to investigate possible changes in the proportion of organic solvents used to produce MS containing water-soluble drugs. A modified quasi-emulsion solvent diffusion technique was used to formulate MS with ethylcellulose and Eudragit RS 100 (MS-EE) or ethylcellulose and HPMCphthalate (MS-EH) using different combinations of ethanol/dichloromethane ratios. The effects of the polymeric composition and organic solvent ratio were evaluated on the morphology, size, swelling, yield, drug content, entrapment efficiency and in vitro release of methylene blue (MB), a hydrophilic drug model. Both polymer combinations resulted in spherical and porous particles. MS-EE was larger (8–13 μm) and displayed higher product yield (62–77%), but MS-EH showed a higher drug entrapment (11–41%), which was higher with an increase in the amount of ethanol amount used. Only MS-EH displayed in vitro MB release during 24 h (70%). ATR-FTIR and FT-Raman analyses did not demonstrate chemical interactions between MB and the polymers. Differential scanning calorimetry, thermogravimetry, and x-ray diffraction confirmed the molecular dispersion of MB in the MS polymer matrix. Ex vivo permeation studies by Franz cells and photoacoustic spectroscopy showed that MB could diffuse out from the polymer matrix and permeate both pig skin and mucosa. The particles were shown to be good carriers for MB and they provided controlled drug release and permeation through skin and mucous tissue; however, the MS particles themselves are not able to permeate these membranes. The use of ethanol in the solvent system constitutes a good strategy to obtain MS of ethylcellulose and HPMCphthalate for delivery of MB and suggests that MS is worthy of investigation as carrier for delivery other hydrophilic drugs.

OH−-free calcium aluminosilicate (CAS) glasses present interesting properties for optical and photonic device applications. Optical properties have direct relation with SiO2 content in the glass composition. However, there is an interval (10–25 wt%) of SiO2 content which was not capable forming glassy-phase in previous works. In this study, the glass-forming ability was investigated as a function of the SiO2 content within this specific interval. The proposal was to use glass frits as precursor material to overcome this difficulty. Glass frits were produced from CAS glasses with 7 and 34 wt% of SiO2. These compositions were chosen by having a well established production procedure. Using glass frits, samples with concentration of 10, 15, 20 and 25 wt% of SiO2 were produced. With the exception of 25 wt%, all the samples vitrified, X-ray diffraction measurements reveal the amorphous nature of the prepared glasses. Raman spectroscopy and differential thermal analysis show that the samples present formation of a single phase in each sample, and these phases are between the limit phases obtained in the 7 and 34 wt% samples. In addition, mechanical, thermal, optical and thermo-optical properties of the samples were accessed. The results show that glass frits method is an alternative solution for the glass production, and, the process does not affect the sample properties comparing with the standard procedure.

At the present time there is no doubt that almost every country is experiencing a revolutionary change in the used devices for artificial lighting whether for public, for domestic or for work place illumination. This movement is taking place towards the substitution of fluorescent lamps to LED-phosphor based devices under the justification of reduction in energy consumption and mitigation of the contamination of environment produced by the mercury of fluorescent lamps. In this aspect, despite of the great effort of worldwide scientists to obtain a white lighting source with the emitting spectrum similar to that of the sunlight, it is recognized that there is still a challenge to be faced of getting luminescent materials with broad band excitation in the UV–Vis regions and large emission in the visible in order to allow tunable white lighting generation. Motivated by this interest, in this paper, Eu2+,3+/Pr3+ co-doped calcium aluminosilicate glasses were synthesized and spectroscopically investigated aiming at the development of smart white lighting devices. A prototype was developed to study the sample with excitation at 445 nm light emission diode (LED). The results indicate high color rendering index (CRI Ra ∼92–95) and tunable correlated color temperature (CCT from 5700 to 6600 K), covering the whole spectral daylight range. By using a second 405 nm LED together with the 445 nm one, the calculated Du’v’ values are suitable for indoor illumination. In this configuration, by adjusting the LEDs intensities it is possible to tune the CCT close to the white lighting region with CRI Ra nearly 95. These characteristics demonstrate that the Eu2+,3+/Pr3+ co-doped OH− calcium aluminosilicate glass is a strong candidate for smart white lighting with LEDs.

We propose a combined pump-probe optical method to investigate heat diffusion properties of solids. We demonstrate single-shot simultaneous laser-induced thermoelastic surface displacement of metals detected by concurrent measurements using photothermal mirror and interferometry. Both methods probe the surface displacement by analyzing the wavefront distortions of the probe beams reflected from the surface of the sample. Thermoelastic properties are retrieved by transient analysis in combination with numerical description of the thermoelastic displacement and temperature rise in the sample and in the surrounding air. This technique presents a capability for material characterization that can be extended to experiments for quantitative surface mapping.

SUMMARY Objectives: To characterize the chemical interactions and analyze the interface of adhesive systems containing 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) and N-methacryloyl glycine (methacrylamide) functional monomers with the dentin in noncarious cervical lesions (NCCLs) compared with artificial defects (ADs). Methods and Materials: Twenty human teeth with natural NCCLs on the buccal surface were used. Class V cavities, similar to NCCLs, were created on the lingual surface to serve as controls. Teeth were randomly allocated to two groups according to the functional monomer in the adhesive (N=10): G1, 10-MDP; and G2, methacrylamide. NCCLs and ADs were characterized by their mineral composition (MC) and degree of demineralization (DD) using micro-Raman spectroscopy, adhesive/dentin chemical interactions (CIs) were assessed with infrared photoacoustic spectroscopy, and interface morphology was evaluated with scanning electron and light microscopy. MC, CI, and DD data were submitted to Shapiro-Wilk and Student t-tests (p Results: Compared with ADs, dentin in NCCLs was hypermineralized (p Conclusions: Results suggest that the G1 adhesive could be applied directly on the superficial sclerotic layer in NCCLs. In contrast, previous cavity preparation should be conducted to improve the micromechanical interaction of G2 with the dentin.

Noble metal embedded glasses have been studied as promising candidates for a variety of technological applications, mainly due to their ability to enhance rare earth luminescence properties. In this work, Ag:Eu-co-doped calcium boroaluminate glasses were prepared and submitted to further heat treatment to form different Ag species. The optical and luminescence properties were investigated in terms of heat treatment times. Absorption spectra showed a successful Eu and Ag ion incorporation in the host, as well as Ag nanoparticle precipitation induced by heat treatment. Upon UV-light excitation, the co-doped glasses exhibited an intense wide emission band centered at about 500 nm, attributed to molecule-like silver species, which combined with the Eu

Objective To investigate the chemical interactions between a high-viscosity glass ionomer cement (GIC) (KetacTM Molar Easymix, 3M ESPE, Seefeld, Bavaria, Germany) and human dentin. It was also analyzed the dynamics of GIC setting mechanism based on the time intervals required for the GIC and the GIC mixed with dentin to achieve stability. Material and Methods Each constituent of GIC – powder (P) and liquid (L) – and powdered dentin (D), as well as the associations P+L, D+L, and P+L+D in the concentrations of 29%, 50%, 65%, 78%, 82%, and 92% of GIC were analyzed with Fourier transform infrared (FTIR) and Raman spectroscopy. Results New optical absorption bands and/or Raman bands, which were not present in P, L, or D, were observed in the associations. The concentrations of 29% and 50% of GIC showed higher interaction, revealing that the amount of dentin influences the formation of new optical absorption or scattering bands. FTIR bands showed that the setting time to achieve bond stability was longer for the high-viscosity GIC (38±7 min) than for the sample with 29% of GIC (28±4 min). Conclusions The analysis revealed the formation of new compounds or molecular rearrangements resulting from the chemical interactions between GIC and dentin. Moreover, this study provides an effective method to evaluate the dynamics of the setting mechanism of GICs.

Objective To evaluate the influence of external energy sources on the dynamic setting process of glass-ionomer restorative materials. Methods Eighteen brands of GIC were studied: Bioglass R (Biodinâmica; G1), Chemfil Rock (Dentsply; G2), Equia Forte (GC; G3), Gold Label 2 (GC; G4), Gold Label 9 (GC; G5), Glass Ionomer Cement Type II — (Shofu; G6), Ionglass R (Maquira; G7), Ion Z (FGM; G8), Ionomaster (Wilcos; G9), Ionofil Plus (Voco; G10), Ionostar Plus (Voco; G11), Ketac Molar easymix (3M ESPE; G12), Magic Glass R (Vigodent; G13), Maxxion R (FGM; G14), Riva Self Cure (SDI; G15), Vidrion R (SS White; G16), Vitro Fil R (Nova DFL; G17) and Vitro Molar (Nova DFL; G18). LED, halogen light or ultrasound (n = 20 for each set) applied for 30 s was used to activate setting, and a control group of each material was allowed to set without activation. Samples were analyzed by FTIR spectroscopy using the ratio of intensities of bands at 1637 cm−1 (carboxylate) and 1720 cm−1 (carbonyl) as a function of time. Means and standard deviations were subjected to ANOVA and Tukey tests (p Results All three activation modes significantly reduced the time at which the carboxylate content became stable in G2, G4, G5, G6, G8, G10, G14, G16, G17 and G18. By contrast, in G1, G7, G12 and G15 no activation source had any significant effect (p > 0.05). Significance External activation sources, namely LED, halogen light and ultrasound, typically but not always increase the setting rate of restorative GICs.

Nowadays there exists a large variety of Ion Selective Electrodes with chalcogenide glasses as sensitive membrane. This short review paper will discuss the development of these sensors for the last almost fifty years. The glass compositions, response modelling, construction methods, parameters evaluation and applications are reviewed. Research breakthroughs and remaining problems on chalcogenide glass Ion Selective Electrodes are discussed.

Onychomycosis is a chronic fungal infection of nails, commonly caused by dermatophyte fungi, primarily species of Trichophyton. Because of the limited drug arsenal available to treat general fungal infections and the frequent failure of onychomycosis treatment, the search for new therapeutic sources is essential, and topical treatment with natural products for onychomycosis has been encouraged. Propolis, an adhesive resinous compound produced by honeybees (Apis mellifera), has shown multiple biological properties including significant antifungal and anti-biofilm activities in vitro. In spite of promising in vitro results, in vivo results have not been reported so far. This study assessed an ethanol propolis extract (PE) as a topical therapeutic option for onychomycosis, including its characterization in vitro and its applicability as a treatment for onychomycosis (from bench to clinic). The in vitro evaluation included analysis of the cytotoxicity and the antifungal activity against the planktonic cells and biofilm formed by Trichophyton spp. We also evaluated the capacity of PE to penetrate human nails. Patients with onychomycosis received topical PE treatments, with a 6-month follow-up period. The results of the in vitro assays showed that PE was non-toxic to the cell lines tested, and efficient against both the planktonic cells and the biofilm formed by Trichophyton spp. The results also showed that PE is able to penetrate the human nail. The results for PE applied topically to treat onychomycosis were promising, with complete mycological and clinical cure of onychomycosis in 56.25% of the patients. PE is an inexpensive commercially available option, easy to obtain and monitor. Our results indicated that PE is a promising natural compound for onychomycosis treatment, due to its ability to penetrate the nail without cytotoxicity, and its good antifungal performance against species such as Trichophyton spp. that are resistant to conventional antifungals, both in vitro and in patients.

Tb3+ doped materials exhibit strong emission in the green (5D4) and weak emission in the UV-blue (5D3) regions. The blue emission can occur from direct UV excitation or by excited state absorption, through 5D4 metastable level. In this paper, we investigate the effect of silica content on the spectroscopic properties of the Tb3+ doped calcium aluminosilicate glasses. The low silica calcium aluminosilicate glass (LSCAS) and calcium aluminosilicate glass (CAS) doped with 0.5 wt% of Tb3+ were prepared and characterized through absorption, excitation, Stokes emission, upconversion emission and 5D4 lifetime decay measurements. The green luminescence in the LSCAS glass presented a fast quenching. The silica influence on this behavior was discussed and a comprehensive interpretation is presented, correlating the Tb3+ luminescence behavior with the silica concentration. Additionally, we analyze the excited state absorption effect on fluorescence transients to 5D4 energy level lifetimes.

International audience; Noble metal embedded glasses have been studied as promising candidates for a variety of technological applications, mainly due to their ability to enhance rare earth luminescence properties. In this work, Ag:Eu-co-doped calcium boroaluminate glasses were prepared and submitted to further heat treatment to form different Ag species. The optical and luminescence properties were investigated in terms of heat treatment times. Absorption spectra showed a successful Eu and Ag ion incorporation in the host, as well as Ag nanoparticle precipitation induced by heat treatment. Upon UV-light excitation, the co-doped glasses exhibited an intense wide emission band centered at about 500 nm, attributed to molecule-like silver species, which combined with the Eu3+ characteristic emission reaches a white light resultant emission. A new excitation band for Eu3+ at 335 nm and a silver luminescence lifetime decrease suggest an energy transfer process from molecule-like Ag to Eu3+ as being responsible for the enhanced PL properties in these glasses. An appropriate combination of a violet LED with the sample emission provides a route to achieve the ideal white light CIE color parameters. The relevant quality color results qualify these glasses as phosphors with high potential for white light emitting devices.