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Nanoemulsions are increasingly gaining importance in the development of topically applied medicine and cosmetic products because their small droplets favor the penetration rates of active compounds into the body. In this scenario, the measurements of their diffusion rates as well as eventual physicochemical changes in the target tissues are of utmost importance. It is also recognized that the use of natural surfactants can avoid allergic reactions as frequently observed for synthetic products. The natural saponins extracted from Sapindus Saponaria have the property of forming foam and are exploited as biocompatible and biodegradable, while cellulose nanocrystals are known to increase the stability of a formulation avoiding the coalescence of drops at the interface. Therefore, nanoemulsions combining natural saponins and cellulose nanocrystals are promising systems that may facilitate greater diffusion rates of molecules into the skin, being candidates to substitute synthetic formulations. This study applied the Photoacoustic Spectroscopy technique to measure the diffusion rates and the physicochemical properties of nanoemulsified formulations containing saponins and cellulose nanocrystals topically applied to the skin. The ex vivo study combined the first-time photoacoustic measurements performed in both ultraviolet-visible and mid-infrared spectral regions. The toxicity of these formulations in L929 cells was also evaluated. The results showed that the formulations were able to propagate throughout the skin to a depth of approximately 756 µm, reaching the dermal side. The non-observation of absorbing band shifting or new bands in the FTIR spectra suggests that there were no structural changes in the skin as well as in the formulations after the nanoemulsions administration. The cytotoxicity results showed that the increase of cellulose nanocrystals concentration decreased cellular toxicity. In conclusion, the results demonstrated the advantage of combining photoacoustic methods in the ultraviolet-visible and mid-infrared spectral regions to analyze drug diffusion and interaction with the skin tissues. Both methods complement each other, allowing the confirmation of the nanoemulsion diffusion through the skin and also suggesting there were no detectable physicochemical changes in the tissues. Formulations stabilized with saponins and cellulose nanocrystals showed great potential for the development of topically administered cosmetics and drugs.

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In this work the thermal diffusivity (D) of Astyanax lacustris fish scale is investigated aiming to use it for environmental integrity certification. The D values were obtained by a relatively simple procedure by a photoacoustic method. The chosen fish species is from wide occurrence in Brasil's basins. It has short migration, and it has also been used as environmental bioindicator. The results obtained in 195 scales sampled from three different streams in the Midwest region in Brazil gives an average value of D ~ 4 × 10-3 cm2/s. ANCOVA analysis demonstrated that D values are able to differentiate among the three basins and indicates that it is dependent on the scales thickness and water conductivity. This last one is strongly affected by biotic and abiotic actions, so that D values measured by photoacoustic method can be used for interpreting the environmental integrity from where the fishes were sampled.

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Objective: This study aimed to analyze the effects of isoflavones from Glycine max (L.) Merr (soy) used topically as a vaginal gel on the induction of vascularization of the vaginal tissue in postmenopausal women.Study design: A placebo-controlled, randomized, double-blind trial was conducted with 22 postmenopausal women, randomly allocated for treatment with Glycine max (L.) Merr isoflavone 4% vaginal gel daily for 12 weeks or with placebo gel for the same period.Main outcome measure: Vaginal microbiopsies were collected before and after the 12-week treatment. Immunohistochemistry analyses were performed to provide a blood vessel count per field in the vaginal tissue, pre and post intervention.Results: The isoflavone group exhibited a significant increase in blood vessels per field relative to baseline, whereas the placebo group showed no difference compared to baseline. There was a significant difference in the increase of the number of blood vessels between the isoflavone and placebo groups.Conclusion: The results showed that local administration of Glycine max (L.) Merr isoflavone gel promoted a significant improvement in the number of blood vessels in the vaginal tissue of postmenopausal women.

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Chemical compounds present on the cuticle of social insects are important in communication, as they are used in recognition of nestmates and sexual partners as well as in caste distinction, varying according to several factors, such as genetic and environmental. In this context, some studies have explored the cuticular chemical profile as a tool for assessing intra- and interspecific differences in social insects, although few studies have investigated this in social wasps. This study aimed to assess the differences in cuticular chemical profiles among different geographic samples of the wasp Mischocyttarus consimilis Zikán. Our hypothesis was that environmental factors are decisive to compose the cuticular chemical profiles of colonies of these social wasps and that there are differences regarding the geographic distribution among colonies. We used Fourier Transform Infrared-Photoacoustic Spectroscopy (FTIR-PAS) to assess the chemical profiles of samples. Our results show that despite there are differences between the cuticular chemical composition of the wasps' samples from different populations, there is no significant correlation compared to the spatial distribution of the colonies nor with the environment. Thus, our hypothesis was refuted, and we can infer that in this species neither exogenous nor genetic factors stand out to differentiate the chemical signature of their colonies, but a combination of both.

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The thermoxidation of biodiesel was monitored using different spectroscopic techniques: UV-Vis and MIR absorption, Raman spectroscopy, and visible fluorescence. As the oxidation progressed, the UV-Vis absorption spectra showed an increase in the spectral range between 34,000 and 26,000 cm-1, while two main fluorescence bands (under ultraviolet excitation) were observed at around 21,000 and 15,000 cm-1. The UV-Vis absorption and fluorescence intensities presented opposite behavior during the processes, irrespective of the temperature used (90, 140, or 190 °C). These effects could be explained by the consumption of natural antioxidants, followed by the formation of primary oxidation compounds. The Raman and MIR absorption results indicated the existence of a cis-trans isomerization effect, followed by the formation of hydroperoxides during the oxidation, with the behavior being the same as that revealed by the UV-Vis absorption and fluorescence analyses. The comparison, under the same conditions, of different spectroscopy techniques that can be used to monitor the stages of thermoxidation of soybean biofuel provides important information for selection of an appropriate technique for evaluating biodiesel integrity.

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We assessed the presence of independent evolving lineages of the trahira, Hoplias malabaricus, one of the few freshwater fish species having wide distribution in the Neotropics which is the region with the highest global diversity of freshwater fish. To achieve that goal, 58 mitochondrial sequences of cytochrome c oxidase subunit I (COI; DNA barcoding) were generated from collected samples and 85 obtained from public databases, which were analyzed in comparison to chromosomal and geological data. The magnitude of genetic diversity found among different sampling sites was greater than 2%. Molecular species delimitation methods indicated the existence of a least four distinct lineages. The recognised cytotypes did not form monophyletic groups, suggesting that the karyotypic macrostructure could be a homoplastic character. The haplotype relationships suggested secondary contacts between the ecoregions of Northern and Northeastern Brazil that were shaped by coastal routes between adjacent watersheds during the Pleistocene epoch and probable exchanges of their ichthyofaunas. Our results indicated that multiple factors have driven the diversification of H. malabaricus, from ancient geological events linked to the reactivation of tectonic faults to more recent occurrences related to eustatic changes in ocean levels. Ultimately, the magnitude of its genetic diversity suggests the necessity of revising its taxonomic status.

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Thermal lens spectroscopy (TLS) in the near-near-infrared region was used to explore the absorptions of overtones and combination bands of sulfentrazone (SFZ) herbicide diluted in methanol. This spectroscopic region was chosen in order to guarantee that only thermal lens effect is noted during the experimental procedure. The results showed that it was possible to detect very low concentrations (~2ng/µL) of SFZ in methanol by determining its thermal diffusivity or the absorption coefficient due to the 3ν(NH)+1δ(CH) combination band. This minimum SFZ concentration is the limit observed by chromatography method. The findings demonstrated that the TLS can be used for precise and accurate assessment of pesticides in ecosystems. Besides, the 3ν(NH)+1δ(CH) combination band at 960nm can be used as a marker for SFZ in methanol.

RESUMO

In the present work, we explored multiple data from different biological levels such as cuticular hydrocarbons, chromosomal features, and mtDNA sequences in the Neotropical social wasp Mischocyttarus consimilis (J.F. Zikán). Particularly, we explored the genetic and chemical differentiation level within and between populations of this insect. Our dataset revealed shallow intraspecific differentiation in M. consimilis. The similarity among the analyzed samples can probably be due to the geographical proximity where the colonies were sampled, and we argue that Paraná River did not contribute effectively as a historical barrier to this wasp.

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Wasps are able to synthesize toxic compounds known as venoms, which form a part of a mechanism to overcome prey and also to defend their colonies. Study of the compounds that constitute these substances is essential in order to understand how this defense mechanism evolved, since there is evidence that the venoms can vary both intra- and interspecifically. Some studies have used liquid and gas chromatography as a reliable technique to analyze these compounds. However, the use of Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) to analyze the variations in venom's chemical profile has been proposed recently. This study evaluated whether the FTIR-PAS technique is effective for assessing the role of environmental factors on intra- and interspecific differences in the venom of the wasps Polybia paulista Von Ihering and Polybia occidentalis Olivier by FTIR-PAS. The colonies were collected in three municipalities of Mato Grosso do Sul, Brazil, in different types of environments. The results showed that the venoms of P. paulista and P. occidentalis differed significantly in profile. In addition, the intraspecific differences in the venom's chemical profile of P. paulista are related to the type of environment where they nested, regardless of the geographical distance between the nests. The FTIR-PAS technique proved to be reliable and effective to evaluate the variations in the venom's chemical profile in social wasps.

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In situ micro-Raman spectroscopy was used to investigate the structural evolution of OH(-)-free calcium aluminosilicate glasses, under high pressure and at room temperature. Evaluation was made of the role of the SiO2 concentration in percalcic join systems, for Al/(Al + Si) in the approximate range from 0.9 to 0.2. Under high pressure, the intensity of the main band related to the bending mode of bridging oxygen ([Formula: see text][T-O-T], where T = Si or Al) decreased gradually, suggesting that the bonds were severely altered or even destroyed. In Si-rich glasses, compression induced a transformation of Q (n) species to Q (n-1). In the case of Al-rich glass, the Al in the smallest Q (n) units evolved from tetrahedral to higher-coordinated Al (([5])Al and ([6])Al). Permanent structural changes were observed in samples recovered from the highest pressure of around 15 GPa and, particularly for Si-rich samples, the recovered structure showed an increase of three-membered rings in the Si/Al tetrahedral network.