Cellulose nanofibers (CNF) have been applied in composite systems due to the abundance of raw material, excellent mechanical and thermal properties. In this work, CNF was prepared from agroindustrial waste and used in specified amounts in polyvinyl alcohol (PVA) composites. The FTIR spectra of CNF, chemically purified cellulose (CPC) and Cassava Agro-industrial Waste (CAW) indicate the removal of hemicellulose and lignin. The increase of the crystallinity phase in CNF was observed, by XRD analysis and neither is observed the transition from cellulose I to II. Thermogravimetric analysis showed displacement that the initial degradation of the CNF over 43 °C degradation proceeds at single step. The chemical and dimensional homogeneity of CNF can be observed with the calculation of the crystalline phase content obtained by deconvoluted dTG curve and XRD spectra, obtaining 80% crystallinity by both techniques. SEM micrographs showed fibers with diameters of 22.30 ± 1.52 nm. An increase in the mechanical properties of PVA was observed with the addition of CNF. With 2.5% CNF in the PVA, the elastic module increased by approximately three times, with the addition of 10% CNF, a saturated system with poor mechanical properties was observed.

RESUMO: O histograma em escala de cinza (HEC) possibilita a mensuração da quantidade e distribuição da frequência de tonalidades de cinza, fornecendo informações quantitativas, tanto sobre a ecogenicidade quanto a ecotextura dos tecidos. Havendo a necessidade de diminuir a subjetividade das imagens ultrassonográficas do ligamento nucal (LN), esse trabalho propôs avaliar o LN por imagens ultrassonograficas modo-B pelo HEC em diferentes idades de cavalos da raça Quarto de Milha. Utilizou 15 cavalos da raça Quarto de Milha saudáveis os quais foram classificados por idade em três grupos diferentes: “baby” (1), “sobreano” (2) e “adulto” (3). Os animais foram submetidos a contenção química para a realização do exame ultrassonográfico. Posteriormente, a ferramenta HEC foi empregada em cada imagem para análise estatística. Houve diferença significativa entre as variáveis “Mean” e “Mode” entre os grupos. O Grupo 1 diferenciou significativamente quando comparado ao Grupo 2 e 3. O Grupo 2 apresentou ecogenicidade superior ao Grupo 1 e 3. Quanto à altura do LN não teve variação considerável entre os grupos. O HEC indicou que a ecogenicidade do LN em cavalos Quarto de Milha varia conforme a idade.

ABSTRACT: The gray scale histogram (GSH) makes it possible to measure the amount and distribution of gray shade frequencies, providing quantitative information on both echogenicity and echotexture of tissues. There is a need to diminish the subjectivity of the ultrasound images of the nuchal ligament (NL). This work proposes to evaluate the NL by ultrasound B-mode GSH images in different ages of Quarter horses. It used 15 healthy Quarter horses, which were classified by age into three different groups: “baby” (1), “sobreano” (2) and “adult” (3). The animals were submitted to chemical restraint for the ultrasound examination. Subsequently, the GSH tool was used in each image for statistical analysis. There was a significant difference between Mean and Mode between groups. Group 1 differed significantly when compared to Group 2 and 3. Group 2 presented superior echogenicity to Group 1 and 3. The height of the NL did not vary considerably between groups. GSH indicated that the echogenicity of NL in Quarter horses varies with age.

ABSTRACT The fruits of guava, Psidium guajava L., Myrtaceae, are cultivated as food and used in agroindustries, generating byproducts or waste that represent environmental problems and require adequate destination. However, these byproducts present high levels of secondary metabolites and have been awakened interest regarding to its reusing. The extract was standardized in ellagic acid concentration by high performance liquid chromatography. The additivation capacity in the in vitro photoprotective efficacy of guava byproduct extract standardized in ellagic acid was verified as a result of its incorporation in cosmetic formulations, comparing it with a standard product. The extract presented synergy with the chemical UV filter (ethylhexyl methoxycinnamate), enhancing the solar protection factor of the phytocosmetic in 17.99%. Besides that, it was possible to show its antioxidant activity and the presence of secondary metabolites such as phenols and flavonoids. According to the results, it is possible to claim that the extract from the guava's agroindustrial byproducts present potential to be studied and reused, applying on the development of innovative products intended to the photoprotection care.

O objetivo deste trabalho foi avaliar a distância genética entre 37 acessos da espécie cultivada Psidium guajava, L. (goiaba) e de araçás do gênero Psidium do banco de germoplasma da Universidade Estadual do Norte Fluminense (UENF), via marcadores moleculares ISSR. Nos 17 marcadores selecionados, foram obtidas 216 bandas polimórficas. Pelo método de agrupamento UPGMA, houve a formação de cinco principais grupos. Os acessos de araçá da espécie P. cattleyanum Sabine , ficaram alocados nos grupos I e II. No grupo II, foi observada, dentro da espécie P cattleyanum, maior proximidade com a goiabeira. No grupo III, ficou alocado o acesso da espécie P. guineense Sw (araçá-do-campo) e dentre os araçás, foi o que ficou mais próximo da goiaba. Os genótipos de goiabeira ficaram alocados do grupo IV e V, confirmando sua alta divergência. Os marcadores moleculares foram eficientes em estimar a distância genética intra e interespecífica.

The objective of this study was to evaluate the genetic distance among 37 accessions of cultivated species Psidium guajava, L. (guava) and Araçás to the genus Psidium to the germplasm colection of the Universidade Estadual Norte Fluminense (UENF) by ISSR molecular markers. In the 17 selected markers, 216 polymorphic bands were obtained. By UPGMA method there was the formation of five main clusters. Accessions of araçá species, P. cattleyanum Sabine, were allocated in groups I and II. In group II was observed within the species P cattleyanum, closer to the guava. In group III was allocated the genotypes of the species P. guineense Sw (araçá-do-campo) and among the araçás, was the most closest to the guava. The guava genotypes were allocated to Group IV and V, confirming their high divergence. Molecular markers were efficient in evaluating intra and interspecific genetic distance for these species.