Abstract Controlled release systems can modify the release rate of drugs and direct them to specific sites of action, making them more effective and/or reducing the adverse effects. The objective of this study was investigated, poly(β-hydroxybutyrate) (PHB) and poly(ε-caprolactone) (PCL) nanospheres to improve the delivery of Simvastatin (SIM). Nanospheres were prepared by the emulsion/evaporation technique of the solvent, varying the amount of SIM added. The SIM quantification was performed using a validated high-performance liquid chromatography method. The average diameter and PDI of formulations without SIM were lower 250 nm and 0.3, respectively. Nanospheres containing 30% of SIM showed values of 265 nm and 0.09, respectively. The average zeta potential was -31.8 mV, suggesting the predominance of repulsive forces that prevent aggregation. In vitro release suggest transport occurs by diffusion. Morphological analysis demonstrated spherical particles and rough surfaces. In conclusion, data suggest that PHB/PCL nanospheres are promising delivery systems to SIM.

Sclareol (SC) is arousing great interest due to its cytostatic and cytotoxic activities in several cancer cell lines. However, its hydrophobicity is a limiting factor for its in vivo administration. One way to solve this problem is through nanoencapsulation. Therefore, solid lipid nanoparticles (SLN-SC) and nanostructured lipid carriers (NLC-SC) loaded with SC were produced and compared regarding their physicochemical properties. NLC-SC showed better SC encapsulation than SLN-SC and was chosen to be compared with free SC in human cancer cell lines (MDA-MB-231 and HCT-116). Free SC had slightly higher cytotoxicity than NLC-SC and produced subdiploid DNA content in both cell lines. On the other hand, NLC-SC led to subdiploid content in MDA-MB-231 cells and G2/M checkpoint arrest in HCT-116 cells. These findings suggest that SC encapsulation in NLC is a way to allow the in vivo administration of SC and might alter its biological properties

ABSTRACT The use of Ti-Ni memory alloys covers several fields of application such as medicine, dentistry, actuators, sensors among others. Because of the thermomechanical behavior of these materials, they are an object of continuous studies and their properties are related to the occurrence of thermoelastic martensitic phase transformations. The thermal analyzes were performed using dilatometry and differential scanning calorimetry to determine the temperatures that occurred transformations during the cooling and heating, as well as to evaluate the influence of the thermal treatments performed by dilatometry. The thermomechanical behavior was also evaluated by the internal friction that measured behavior damping considering the structural and microstructural changes. The calorimetry measurements indicated suppression of the R phase through decomposition of precipitates of Ti3N4after the thermal treatments, that were corroborated by dilatometry and microhardness. This phase was also studied by the technique of internal friction, which showed that the mechanical damping coefficient increased as a function of temperature, due to the movement of the defects induced by tension.

RESUMO Introdução A utilização de questionários sintoma-específicos no câncer de cabeça e pescoço (CCP) em conjunto com avaliações objetivas da deglutição pode ser sensível às mudanças na qualidade de vida (QV) decorrentes da disfagia, porém é uma ferramenta pouco utilizada como complemento de avaliações clínicas. Objetivo analisar a associação entre o questionário de disfagia M. D. Anderson (MDADI) com a videofluoroscopia (VF) da deglutição em pacientes tratados do CCP. Método Estudo retrospectivo, com revisão de prontuários, dados da VF e do questionário de disfagia MDADI. Foram incluídos indivíduos maiores de 18 anos, tratados do câncer de cavidade oral, orofaringe, hipofaringe e laringe, independentemente do tratamento curativo. Para o exame de VF, foram consideradas as deglutições de 5 e 20 ml na consistência néctar. O teste não paramétrico de Mann-Whitney foi utilizado para avaliar a associação entre o questionário MDADI e a VF. Resultados Casuística de 39 indivíduos, predomínio de homens, 34 (87,18%), e média de idade de 61 anos. Prevalência de câncer de cavidade oral, 16 (41,03%). Vinte e dois (56,4%) possuíam estádio clínico IV. Cirurgia isolada foi o tratamento mais prevalente, 16 (41,03%). Vinte indivíduos (51,28%) se alimentavam por via oral. A média total (MT) do MDADI foi de 63,36. Na correlação da VF com o MDADI, observou-se associação significante entre MT, domínio emocional (DE) e domínio físico (DFis) com penetração para 5 ml. Penetração e aspiração com 20 ml determinou prejuízo para questão global (p=0,018 e p=0,0053), DE (p=0,0012 e p=0,027), DFis (p=0,0002 e p=0,0051) e MT (p=0,0023 e p=0,0299), respectivamente. A presença de estase não determinou piora da QV. Conclusão Pacientes tratados do CCP que apresentam penetração/aspiração demonstram impacto na qualidade de vida nos DE e DFis.

ABSTRACT Introduction The use of symptom-specific questionnaires on head and neck cancer (HNC), together with objective swallowing measures, can be sensitive to changes in quality of life (QoL) resulting from dysphagia, but this tool is not broadly used as a complement to clinical evaluations. Purpose To analyze the correlation between the M. D. Anderson Dysphagia Inventory (MDADI) questionnaire and videofluoroscopy (VF) in patients treated for head and neck cancer. Methods This is a retrospective study with review of clinical data, VF and MDADI results. The study sample was composed of adult patients (>18 y.o.) treated for tumors at the oral cavity, oropharynx, hypopharynx, and larynx, regardless of treatment type. For the VF examination, swallowing of 5 and 20 ml of nectar-thick liquids were considered. The Mann-Whitney nonparametric test was applied to evaluate the correlations between the MDADI and VF. Results Thirty-nine patients, mostly men (87.18%), with mean age of 61 years participated in the study. Most patients (16) presented oral cavity tumors (41.03%). Twenty-two patients were in advanced clinical stage (IV). Surgery was the most prevalent treatment (41.03%). Approximately half of the participants (20) received oral feeding. The total mean (TM) on the MDADI was 63.36. Comparison between VF and MDADI data showed significant correlation between TM, emotional domain (ED), and physical domain (PD) with penetration during the swallowing of 5 ml. Penetration and aspiration with 20 ml determined worse QoL on the global (p=0.018 and p=0.0053), emotional (p=0.0012 and p=0.027) and physical (p=0.0002 and p=0.0051) domains, and TM (p=0.0023 and p=0.0299), respectively. The presence of stasis did not determine worse QoL. Conclusion Patients treated for HNC who presented penetration/aspiration showed worse QoL on the emotional and physical domains of the MDADI.

Microstructural characterization of steels is normally performed using optical and scanning electron microscopy which allows identifying the most important phases and constituents in steels. Nevertheless, the microstructural complexity of some constituents during continuous cooling hinders the characterization of them; especially bainitic and martensitic microstructures provide rich morphology characteristics tough to solve properly. In this sense, atomic force microscopy was applied in order to provide complementary information to optical and scanning electronic microscopy in continuous cooling microstructural constituents of a low carbon and a Nb microalloyed low carbon steels. The samples were austenitized, some of them were quenched directly from austenitization temperature and others were cooling to Ar3 and Ar1 temperatures and then quenched. The samples quenched from austenitization temperature showed predominantly bainitic and martensitic microstructures, some microstructural characteristics were only elucidated with the combination between scanning electron microscopy and atomic force microscopy. On the other hand, the samples quenched from Ar3 temperature showed polygonal ferrite and martensite morphologies. Atomic force microscopy has also indicated the occurrence of bainitic ferrite. Concerning samples quenched from Ar1 temperature, the microstructure was essentially ferrite and fine perlite.

A descrição microestrutural de aços é feita frequentemente por meio das técnicas de microscopia óptica e eletrônica de varredura, que permitem identificar as principais fases e constituintes presentes. A complexidade microestrutural dos constituintes formados em maiores taxas de resfriamento, durante o resfriamento contínuo, dificulta a caracterização destes. Em especial, as microestruturas bainíticas e martensíticas fornecem características morfológicas de difícil visualização. A microscopia de força atômica foi usada visando complementar a microscopia óptica e eletrônica de varredura na descrição dos produtos do resfriamento contínuo de um aço baixo carbono com e sem adição de Nb. As amostras foram austenitizadas, algumas temperadas, enquanto outras resfriadas até Ar3 e Ar1 e, então, temperadas. A microscopia de força atômica permitiu determinar que, para ambos os aços, as amostras temperadas, a partir da temperatura de austenitização, apresentaram microestrutura predominantemente martensítica e bainítica. Por outro lado, as amostras interrompidas na Ar3 apresentaram ferrita poligonal e martensita e a formação de ferrita bainítica. Para as amostras temperadas a partir da Ar1, a microestrutura foi essencialmente ferrita e perlita fina.

The influences of the chemical composition and heating rate have been studied in 300 and 350 maraging steels using dilatometry. For these tests, heating was carried out with heating rates of 1, 10 and 28 °C/s. The results have shown that the precipitation mechanism for both materials in the studied range is by lattice diffusion. Furthermore, Co and Ti contents influence strongly the precipitation. The lattice diffusion mechanism in the martensite reversion is influenced by Ni and Co contents and heating rate. For small heating rates ( ~1 °C/s) this mechanism prevails in the 300 maraging steel while for the 350 maraging steel has a minor importance. The mechanism of martensite reversion for 350 maraging steel in the studied range is mainly by shear mechanism. For higher heating rates (~28 ºC/s) the shear mechanism prevails in both maraging steels.

High quality KMo4O6 single crystals with tetragonal structure (space group P4/mbm) have been prepared by fused salt electrolysis. The crystals were studied by scanning electron microscopy (SEM), X-ray diffractometry, electrical resistivity, and magnetization measurements. X-ray powder diffraction patterns and SEM have given some information on the growth of single crystals. Electrical resistivity as a function of temperature shows that the KMo4O6 compound is a bad metal with resistivity change of approximately 30% in the temperature range from 2 to 300K. A metal-insulator transition (MIT), observed at approximately 110K, has been also confirmed for this material. Magnetization as a function of temperature agrees with previous report, however a magnetic ordering has been observed in M(H) curves in the whole temperature range.

The aim of this work was to characterize thin interference films grown on the surface of AISI 304 stainless steel for decorative purposes. Films were grown in a sulphochromic solution at room temperature by an alternating pulse current method. The morphology and chemical state of the elements in the films were investigated by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), glow discharge optical emission spectrometry (GDOES), and infrared Fourier transform spectroscopy (FTIR). Depth-sensing indentation (DSI) experiments and wear abrasion tests were employed to assess the mechanical resistance of the films. The coloration process resulted in porous thin films which increased the surface roughness of the substrate. The interference films mainly consisted of hydrated chromium oxide containing iron. Increasing film thickness produced different colors and affected the mechanical properties of the coating-substrate system. Thicker films, such as those producing gold and green colors, were softer but more abrasion resistant.

Equal Channel Angular Pressing (ECAP) is the most prominent SPD (Severe Plastic Deformation) method for the production of ultrafine and nanostructured metals, and has been extensively employed and analyzed. This technique was applied to a Pb-4%Sb alloy at room temperature, in order to study its effect on a low melting point and multiphase metallic material. The material was subjected to effective strains higher than 9, after 8 passes of processing, where dynamic and static recrystallization are expected during and after each pass. This eliminates any grain refinement and allows the analysis only of the microstructural effects associated with second phase redistribution and eventual precipitate dissolution. ECAP followed route C, which eliminates structural alignment after each even ECAP pass, facilitating the study of the microstructural evolution. It is shown that three ECAP passes are necessary to completely break the lamellar structure of the as cast strucure and that antimony dissolves into the lead rich matrix. Dynamic recrystallization and structural changes reduce the material strength and change the flow curve format.