Photoacoustic for thermal diffusivity determination of fish scale: A methodology for environmental integrity monitoring.

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.

Intraspecific Cuticular Chemical Profile Variation in the Social Wasp Mischocyttarus consimilis (Hymenoptera, Vespidae).

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.

Comparison of optical spectroscopy techniques for monitoring the stages of thermoxidation of soybean biodiesel.

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.

Spectral refractive index technique for monitoring the beer mashing process.

During beer production, the mashing process is fundamental for extraction of the main sugars from the starch. The quantification of these fermentable sugars during the process provides a measure of the alcoholic content of the final beer. Therefore, monitoring of the sugar composition during beer production is very important for obtaining a quality product. This paper demonstrates the potential of white light interferometry (WLI) for monitoring the extraction of sugars in different mashing processes, by observing the refractive index of the mixture. All the mashings presented linear increases of the refractive index during the temperature steps, which were influenced by the concentrations of sugars produced in each step. Cauchy parameters obtained by refractive index interpretation showed the influence of carbohydrates on absorption in the infrared region, and amino acids on absorption in the ultraviolet region. Strong correlation was obtained between the refractive index and °Bx values, indicating that the WLI technique is a potential analytical method for monitoring the mashing process during beer production.

Near-near-infrared thermal lens spectroscopy to assess overtones and combination bands of sulfentrazone pesticide.

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.

Integrated Analyses of Cuticular Hydrocarbons, Chromosome and mtDNA in the Neotropical Social Wasp Mischocyttarus consimilis Zikán (Hymenoptera, Vespidae).

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.

Variation in Venoms of Polybia Paulista Von Ihering and Polybia Occidentalis Olivier (Hymenoptera: Vespidae), Assessed by the FTIR-PAS Technique.

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.

Measurements of refractive indices and thermo-optical coefficients using a white-light Michelson interferometer.

A dispersive white-light Michelson interferometer was used to determine the wavelength dependence of the refractive index (n) in the visible range from 425 to 775 nm and the thermo-optical coefficient (dn/dT) of fused silica (FS) and borosilicate glass (BK7). For FS, the values obtained for n and dn/dT at 546 nm were 1.46079 and 11.3×10-6 K-1, respectively, while the values for BK7 glass were 1.51825 and 2.2×10-6 K-1, respectively, which is in good agreement with the literature. The accuracy of the methodology used for n was almost 10-6, enabling precise spectroscopic characterization of materials across a wide spectral range.

In situ structural analysis of calcium aluminosilicate glasses under high pressure.

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.

Morphological and Chemical Characterization of the Invasive Ants in Hives of Apis mellifera scutellata Lepeletier (Hymenoptera: Apidae).

Apiculture in Brazil is quite profitable and has great potential for expansion because of the favorable climate and abundancy of plant diversity. However, the occurrence of pests, diseases, and parasites hinders the growth and profitability of beekeeping. In the interior of the state of São Paulo, apiaries are attacked by ants, especially the species Camponotus atriceps (Smith) (Hymenoptera: Formicidae), which use the substances produced by Apis mellifera scutellata (Lepeletier) (Hymenoptera: Apidae), like honey, wax, pollen, and offspring as a source of nourishment for the adult and immature ants, and kill or expel the adult bees during the invasion. This study aimed to understand the invasion of C. atriceps in hives of A. m. scutellata. The individuals were classified into castes and subcastes according to morphometric analyses, and their cuticular chemical compounds were identified using Photoacoustic Fourier transform infrared spectroscopy (FTIR-PAS). The morphometric analyses were able to classify the individuals into reproductive castes (queen and gynes), workers (minor and small ants), and the soldier subcaste (medium and major ants). Identification of cuticular hydrocarbons of these individuals revealed that the eight beehives were invaded by only three colonies of C. atriceps; one of the colonies invaded only one beehive, and the other two colonies underwent a process called sociotomy and were responsible for the invasion of the other seven beehives. The lack of preventive measures and the nocturnal behavior of the ants favored the invasion and attack on the bees.

Fluorescence analysis of iodinated acetophenone derivatives.

In the present paper the synthesis and optical characterization of iodinated acetophenone, 4-hydroxy-3-iodoacetophenone and 4-hydroxy-3,5-diiodoacetophenone obtained from 4-hydroxyacetophenone, were carried out. The optical features of iodinated molecules were determined by performing the UV-Vis absorption, fluorescence and thermal lens spectroscopies. The results showed that the optical properties of the 4-hydroxyacetophenone is altered when the iodine atom is inserted, as substituent, in the aromatic ring. Although it was determined that the optical feature was changed when one iodine atom was inserted in the aromatic ring (4-hydroxy-3-iodoacetophenone), the results revealed that emission behavior was strongly altered when two iodine atoms (4-hydroxy-3,5-diiodoacetophenone) were acting as substituents: the fluorescence quantum efficiency increases approximately 60%.

Fourier transform infrared photoacoustic spectroscopy as a potential tool in assessing the role of diet in cuticular chemical composition of Ectatomma brunneum.

The cuticular chemical composition plays a significant role in the recognition of nest mates in social insects, thus functioning as a chemical signature of the colony. The structure of cuticular chemicals is subject to interference from genetic and exogenous factors, including diet. In this study, various colonies of the Ectatomma brunneum ant were removed from their natural environment and housed in a laboratory to monitor the response of the cuticular chemical composition to dietary changes. Analyses were performed using gas chromatography and Fourier transform infrared photoacoustic spectroscopy, which has not been previously used for this type of analysis. The results indicate that this method is useful for analyzing biological and natural systems. We observed changes in the chemical signature with food traces in the first 30 days under feed control. Therefore, genetic information may not be the only criterion that can be used to describe the chemical signature of a species; environmental variations also influence recognition signals. Furthermore, these results reinforce the reliability of the Fourier transform infrared photoacoustic spectroscopy method.

Levantamento etnobotânico das plantas medicinais utilizadas pela comunidade de Inhamã, Pernambuco, Nordeste do Brasil / An ethnobotanical survey of medicinal plants used by the rural community of Inhamã, state of Pernambuco, Northeastern Brazil

Avaliou-se o conhecimento, uso, obtenção e indicação terapêutica de plantas utilizadas pela comunidade rural de Inhamã, situada no município de Abreu e Lima, PE, Brasil. Foram realizadas entrevistas semi-estruturadas com 75 moradores. Foram citadas 155 espécies, distribuídas em 112 gêneros e 59 famílias. Conforme a indicação terapêutica, as espécies foram agrupadas em sistemas corporais reconhecidos pela Organização Mundial de Saúde e o índice de importância relativa (IR) foi calculado para cada espécie. Destacaram-se pelo número de espécies, as famílias: Asteraceae, Fabaceae e Lamiaceae. As doenças mais citadas estiveram relacionadas aos sistemas respiratório e gastrointestinal. Ocimum gratissimum, alfavaca, apresentou o maior valor de IR (2,0), seguido por Lippia alba, erva cidreira (1,6), Mentha villosa, hortelã pequena (1,6) e Musa paradisiaca, banana (1,5), indicadas para tratamento de transtornos dos sistemas respiratório, digestório e nervoso. Apenas 11% das espécies citadas tiveram prescrições médicas. Inhamã diferencia-se de outras comunidades próximas a centros urbanos porque os moradores cultivam a maioria das espécies medicinais que consomem.

This study evaluated the extent of knowledge and use and the acquisition of medicinal plants in the rural community of Inhamã, located in the municipality of Abreu e Lima in the state of Pernambuco, Brazil. Medical indications for medicinal plants in this community were also characterized. We conducted semi-structured interviews with 75 community residents. A total of 155 plant species were reported, distributed among 112 genera and 59 families. Species were grouped by body system benefitted according to the code established by the World Health Organization, and relative importance (RI) was calculated for each species. The most represented families were Asteraceae, Fabaceae, and Lamiaceae. The majority of the disease symptoms reported was related to the respiratory and gastrointestinal systems. The Ocimum gratissimum, clove basil, presented the greatest RI value (2.0), followed by Lippia alba, bushy lippia (1.6), Mentha villosa, mint (1.6), and Musa paradisiaca, banana (1.5), all of which are used to treat ailments of the respiratory, gastrointestinal and nervous systems. Of the species reported, only 11% have medical indications. Inhamã differs from other communities located near urban centers, as the local residents cultivate the majority of the medicinal plants they use.

Resonant excited state absorption and relaxation mechanisms in Tb3+-doped calcium aluminosilicate glasses: an investigation by thermal mirror spectroscopy.

Resonant excited state absorption (ESA) and relaxation processes in Tb(3+)-doped aluminosilicate glasses are quantitatively evaluated. A model describing the excitation steps and upconversion emission is developed and applied to interpret the results from laser-induced surface deformation using thermal mirror spectroscopy. The fluorescence quantum efficiency of level (5)D(4) was found to be close to unity and concentration independent while, for the level (5)D(3), it decreases with Tb(3+) concentration. Emission spectroscopy measurements supported these results. ESA cross sections are found to be more than three orders of magnitude higher than the ground state absorption cross section.

Modeling the population lens effect in thermal lens spectrometry.

We report a theoretical model and experimental results for laser-induced lensing in solids. The model distinguishes and quantifies the contributions from population and thermal effects. Laser-induced lensing in ytterbium-doped fluorozirconate glass ZBLAN:Yb(3+) is measured, and the thermal and optical properties obtained from analyzing the data with the proposed model agree well with published values. Photothermal techniques are used extensively for the investigation of laser and laser-cooling materials, and the model developed here enables the interpretation of convoluted laser-induced lensing signals that have contributions from different sources.

Age-related changes in the surface pheromones of the wasp Mischocyttarus consimilis (Hymenoptera: Vespidae).

One of the most important attributes that allowed the evolution and maintenance of sociality in insects is their ability to distinguish members of their own colonies. The capacity for individual recognition in social insects is mediated by chemical signals that are acquired soon after the adult emerges, and vary according to the tasks performed by individuals in their colonies. We determined the time when adults of the wasp Mischocyttarus consimilis acquire the chemical signature of their colonies, as well as the variation in the cuticular hydrocarbon profiles of the exoskeleton of individuals, according to their functions in the colony. The method used was Fourier transform infrared photoacoustic spectroscopy directly on the gaster of each individual. Young wasps take three to four days to acquire the colony's chemical signature, with a small change on the fifth day, when the cuticular hydrocarbon profile of the workers is more similar to that of the queens than that of the males, probably because they are of the same sex, but primarily because of the similarity of tasks executed by these two groups of females in the colonies.

Thermal lens spectroscopy for the differentiation of biodiesel-diesel blends.

Thermal lens (TL) spectroscopy was applied to biofuels to test its potential to distinguish diesel from biodiesel in blended fuels. Both the heat and mass diffusion effects observed using a TL procedure provide significant information about biodiesel concentrations in blended fuels. The results indicate that the mass diffusivity decreases 32% between diesel and the blend with 10% biodiesel added to the diesel. This simple TL procedure has the potential to be used for in loco analyses to certify the mixture and quality of biodiesel-diesel blends.

Tunable color temperature of Ce3+/Eu2+, 3+ co-doped low silica aluminosilicate glasses for white lighting.

In this paper we report results of tunable lighting in Ce(3+)/Eu(2+,3+) doped low silica calcium aluminosilicate glass. Optical spectroscopy experiments indicate that there is a red color compensation from Eu(2+) and Eu(3+) to the green emission from Ce(3+), resulting in a broad and tunable emission spectra depending on the excitation wavelength. This result analysed in the CIE 1976 color diagram shows a close distance from the Plank emission and a correlated color temperature, varying from 5200 to 3500K. This indicates that our system can be easily excited by GaN based blue LEDs, being an interesting phosphor for white lighting devices.

Levantamento etnobotânico de plantas medicinais em área de caatinga no município de São José de Espinharas, Paraíba, Brasil / Ethnobotanical survey of medicinal plants in a caatinga area in São José de Espinharas Municipality, Paraíba State, Brazil

Este trabalho teve como objetivo realizar levantamento das plantas medicinais utilizadas pela comunidade de São José de Espinharas, a fim de registrar e preservar o conhecimento popular. A metodologia usada foi de entrevistas semi-estruturadas, com observações participantes, coleta e identificação do material botânico e preparação de exsicatas, resultando em lista de 82 espécies de 38 famílias diferentes. São fornecidas as informações nomenclatura popular e botânica, uso terapêutico, parte utilizada, forma de uso, modo de preparo e doenças tratadas. As raízes (30 por cento) foram ás partes mais utilizadas e a forma de preparo foi lambedor (32 por cento). O conhecimento sobre os usos e modos de preparo provém em geral, dos familiares (85 por cento). Com esses resultados, verifica-se a interação da população local com a flora e utilização relacionada a aspectos sociais, econômicos, culturais e às mudanças ambientais.

The aim of this study was to perform a survey of medicinal plants used by the community of São José de Espinharas, Paraíba State, Brazil, in order to record and preserve the folk knowledge. The adopted methodology was based on semi-structured interviews, with participating observations, botanical material collection and identification, and voucher preparation, resulting in a list of 82 species of 38 different families. The following information was provided: folk and botanical nomenclature, therapeutic application, used plant part, forms of use, method of preparation and treated diseases. Roots (30 percent) constituted the part most frequently used and syrup (32 percent) was the predominant method of preparation. The knowledge of uses and methods of preparation are generally handed down in the family (85 percent). Based on those results, there is an interaction of the local population with the flora and its use is related to social, economical and cultural aspects and environmental changes.

High values of gain cross section and luminescence quantum efficiency in OH(-)-free Ti3+-doped low-silica calcium aluminosilicate glass.

We recently reported that Ti(3+)-doped low-silica calcium aluminosilicate glass presents long luminescence lifetime (170 micros) and broad emission band (190 nm) shifted toward the visible region when compared with those from Ti(3+):sapphire single crystal and Ti(3+)-doped glasses [Phys. Rev. Lett.100, 027402 (2008)]. Here we demonstrate that this glass also shows high values of both gain cross section (approximately 4.7 x 10(-19) cm(2)) and luminescence quantum efficiency (approximately 70%). By comparing these values with those for Ti(3+):sapphire crystal, we can conclude that the studied Ti(3+)-doped glass is a promising system for tunable solid-state lasers.