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Este artigo é um ensaio teórico que apresenta reflexões, ações e questionamentos que podem ser considerados na constituição de perspectivas epistemológicas para a formação docente partir da epistemologia da prática. Entende-se que a complexidade e a potencialidade de coordenação de conceitos oriundos de diferentes elucidações, bem como seus limites de aproximação, podem contribuir na constituição dessas perspectivas. Entre esses conceitos estão, por exemplo, os conceitos de professor reflexivo e investigativo, bem como de aprendizagem situada em contexto e igualmente de profissionalização docente.

We present the analysis of three faint clusters of the Small Magellanic Cloud RZ82, HW42 and RZ158. We employed the SOAR telescope instrument SAM with adaptive optics, allowing us to reach to V~23-24 mag, unprecedentedly, a depth sufficient to measure ages of up to about 10-12Gyr. All three clusters are resolved to their centres, and the resulting colour-magnitude diagrams (CMDs) allow us to derive ages of 3.9, 2.6, and 4.8Gyr respectively. These results are significantly younger than previous determinations (7.1, 5.0, and 8.3Gyr, respectively), based on integrated photometry or shallower CMDs. We rule out older ages for these clusters based on deep photometry and statistical isochrone fitting. We also estimate metallicities for the three clusters of [Fe/H]=-0.68, -0.57 and -0.90, respectively. These updated ages and metallicities are in good agreement with the age-metallicity relation for the bulk of SMC clusters. Total cluster masses ranging from ~7-11x10^3Mo were estimated from integrated flux, consistent with masses estimated for other SMC clusters of similar ages. These results reduce the number of SMC clusters known to be older than about 5 Gyr and highlight the need of deep and spatially resolved photometry to determine accurate ages for older, low-luminosity SMC star clusters., Accepted for publication as MNRAS letter, 5 pages, 5 figures

Quaternary fossils from limestone caves bear various diagenetic features due to the complex nature of sedimentary processes. However, few studies have addressed the problem of diagenetic changes in fossils from tropical-wet environments. We study Quaternary fossil bones from different sites of a tropical limestone cave in northeastern Brazil. These fossils show diverse diagenetic features. The approach encompassed the use of scanning electron microscopy, Raman spectroscopy, and X-ray diffraction to understand the modification of the fossil bone structure, chemical composition, and mineral assemblage during the diagenesis processes. We describe a model for fossil diagenesis in tropical limestone caves that involves early and advanced diagenetic stages, which produce two routes with different endmembers. The diagenesis in the cave alters the crystallinity and ordering of hydroxyapatite. The recrystallization of hydroxyapatite appears to be strongly influenced by dripping water that is rich in calcium carbonate, which leads to crystal formation with higher crystallinity. In the absence of calcium carbonate, hydroxyapatite diagenesis involves crystal growth but not necessarily dissolution of the original material, which enables remarkable preservation of the biological structure.

MicroRNAs (miRNAs) are short non-coding RNA molecules acting as important posttranscriptional gene and protein expression regulators in cancer. The study goal was to examine VEGFA (vascular endothelial growth factor A) expression in hepatocellular carcinoma (HCC) cell lines upon transfection miR-612, miR-637, or miR-874. Methods: MiR-612 mimics, miR-637 mimics, or miR-874 inhibitors were transfected using Lipofectamine RNAiMax in both HCC cell lines, HepG2 and HuH-7. Real-time PCR, Western blotting, and ELISA methods were used to evaluate VEGFA regulation by the miRNAs. Results: Gene and protein expression levels of VEGFA were down-expressed in both cell lines, HepG2 and HuH-7, transfected with miR-612 or miR-637. Transfection with miR-874 inhibitor showed an increase in VEGFA gene expression in HepG2 and HuH-7 cell lines; however, no regulation was observed on VEGFA protein expression by miR-874 inhibition. Correlation analysis between miRNAs and VEGFA protein expression showed that miR-637 and miR-874 expression present inversely correlated to VEGFA protein expression. Conclusions: VEGFA was down-regulated in response to hsa-miR-612 or hsa-miR-637 overexpression; however, the modulation of VEGFA by miR-874 was observed only at the gene expression and thus, needs further investigation.

The structure of the Small Magellanic Cloud (SMC) is very complex, in particular in the periphery that suffers more from the interactions with the Large Magellanic Cloud (LMC). A wealth of observational evidence has been accumulated revealing tidal tails and bridges made up of gas, stars and star clusters. Nevertheless, a full picture of the SMC outskirts is only recently starting to emerge with a 6D phase-space map plus age and metallicity using star clusters as tracers. In this work, we continue our analysis of another outer region of the SMC, the so-called West Halo, and combined it with the previously analysed Northern Bridge. We use both structures to define the Bridge and Counter-bridge trailing and leading tidal tails. These two structures are moving away from each other, roughly in the SMC-LMC direction. The West Halo form a ring around the SMC inner regions that goes up to the background of the Northern Bridge shaping an extended layer of the Counter-bridge. Four old Bridge clusters were identified at distances larger than 8 kpc from the SMC centre moving towards the LMC, which is consistent with the SMC-LMC closest distance of 7.5 kpc when the Magellanic Bridge was formed about 150Myr ago; this shows that the Magellanic Bridge was not formed only by pulled gas, but it also removed older stars from the SMC during its formation. We also found age and metallicity radial gradients using projected distances on sky, which are vanished when we use the real 3D distances., 14 pages, 8 figures + appendix. Accepted for publication in MNRAS

We present a study of the internal structure of 82 star clusters located at the outer regions of the Large Magellanic Cloud and the Small Magellanic Cloud using data of the VISCACHA Survey. Through the construction of the minimum spanning tree, which analyzes the relative position of stars within a given cluster, it was possible to characterize the internal structure and explore the fractal or subclustered distribution for each cluster. We computed the parameters m (which is the average length of the connected segments normalized by the area), s (which is the mean points separation in units of cluster radius), and Q (the ratio of these components). These parameters are useful to distinguish between radial, homogeneous, and substructured distributions of stars. The dependence of these parameters with the different characteristics of the clusters, such as their ages and spatial distribution, was also studied. We found that most of the studied clusters present a homogeneous stellar distribution or a distribution with a radial concentration. Our results are consistent with the models, suggesting that more dynamically evolved clusters seem to have larger Q values, confirming previous results from numerical simulations. There also seems to be a correlation between the internal structure of the clusters and their galactocentric distances, in the sense that for both galaxies, the more distant clusters have larger Q values. We also paid particular attention to the effects of contamination by non-member field stars and its consequences finding that field star decontamination is crucial for these kinds of studies., Comment: 9 pages, 11 figures, accepted for publication in MNRAS

A novel pigment of β-LiAlSi2O6:Cr ceramic was developed by a partial proteic sol-gel process, using gelatin as a ligand. X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and visible and near-infrared diffuse reflectance spectroscopy (vis-NIR DRS) were performed. XRD results confirmed that the crystal structure of the lattice corresponded to β-LiAlSi2O6 (or β‑spodumene), and the addition Cr3+ ions by doping did not interfere in the formation of this crystalline phase. EDS confirmed the homogeneous existence of Cr3+ dopant in β‑LiAlSi2O6 particles. From the vis‑NIR DRS, selective absorption of visible light wavelengths was identified in the bands of 425 nm and 600 nm, resulting in the perception of a yellowish-green color when β-LiAlSi2O6 is doped with Cr3+. CIE-XYZ colorimetric coordinates were generated to characterize the resulting colors. The obtained results demonstrated the viability of β‑LiAlSi2O6:Cr synthesis by a proteic sol‑gel route and its great potential for obtaining a yellowish-green ceramic pigment.

A tomografia computadorizada (TC) representa uma grande porcentagem da dose de radiação em exposições médicas. Portanto, otimizar a proteção do paciente tem sido uma prática com uma discussão importante. Este estudo tem como objetivo estimar a dose absorvida em órgãos e tecidos relevantes em tomografias computadorizadas de crânio em pacientes adultos com base na modulação automática da corrente do tubo (mA) e do produto atual-tempo (mAs) e índice de kerma no ar volumétrico (C VOL) Para tanto, esses parâmetros foram coletados durante três bimestres em duas instituições com amplo atendimento em Petrolina / PE. Um do setor privado, denominado instituição A e outro do setor público, denominado instituição B. A avaliação da dose foi realizada por meio do software de simulação CALDose_XCT. Os resultados mostraram que os valores médios de mA e mAs por bimestre foram menores na instituição A, onde o controle automático de exposição (AEC) foi ativado, seguindo as orientações de boas práticas em tomografias. O C VOL apresentou valores médios dentro dos níveis recomendados, embora na instituição B esse parâmetro tenha apresentado maior magnitude. Nas simulações, a instituição B apresentou maiores doses absorvidas nas estruturas relevantes, corroborando com a menor otimização de mA, mAs e C VOL. Este trabalho mostrou a existência de ligação entre os parâmetros radiológicos e a dose absorvida no paciente, sugerindo a realização de estudos de otimização em exames de TC de crânio.

Context. RR Lyrae stars are useful standard candles allowing one to derive accurate distances for old star clusters. Based on the recent catalogues from OGLE-IV and Gaia Early Data Release 3 (EDR3), the distances can be improved for a few bulge globular clusters. Aims. The aim of this work is to derive an accurate distance for the following six moderately metal-poor, relatively high-reddening bulge globular clusters: NGC 6266, NGC 6441, NGC 6626, NGC 6638, NGC 6642, and NGC 6717. Methods. We combined newly available OGLE-IV catalogues of variable stars containing mean I magnitudes, with Clement's previous catalogues containing mean V magnitudes, and with precise proper motions from Gaia EDR3. Astrometric membership probabilities were computed for each RR Lyrae, in order to select those compatible with the cluster proper motions. Applying luminosity-metallicity relations derived from BaSTI $\alpha$-enhanced models (He-enhanced for NGC 6441 and canonical He for the other clusters), we updated the distances with relatively low uncertainties. Results. Distances were derived with the I and V bands, with a $5-8\%$ precision. We obtained 6.6 kpc, 13.1 kpc, 5.6 kpc, 9.6 kpc, 8.2 kpc, and 7.3 kpc for NGC 6266, NGC 6441, NGC 6626, NGC 6638, NGC 6642, and NGC 6717, respectively. The results are in excellent agreement with the literature for all sample clusters, considering the uncertainties. Conclusions. The present method of distance derivation, based on recent data of member RR Lyrae stars, updated BaSTI models, and robust statistical methods, proved to be consistent. A larger sample of clusters will be investigated in a future work., Comment: 11 pages, 7 figures. Accepted for publication in A&A

From Obsidian silicate, in its natural form, pellets were manufactured adding Teflon to the material in powder. These pellets were exposed to the gamma radiation beams of a 60Co source in a dose interval from 10 Gy to 10 kGy. The Obsidian in powder was investigated in relation to its physical and chemical characteristics, by means of the X-ray diffraction, scanning electronic microscopy and energy-dispersive X-ray spectroscopy techniques. After the irradiation procedure, the signal of the samples was evaluated by means of three techniques: thermoluminescence (TL), optically stimulated luminescence (OSL) and thermally stimulated exoelectron emission (TSEE). The objective of this work was to verify the TL, OSL and TSEE response of the Obsidian+Teflon pellets after exposure to high doses of gamma radiation. Different response characterization tests were performed, as TL and TSEE emission curves, OSL signal decay, reproducibility, dose-response curves, lower detection limits and fading. From these results, it can be observed that the Obsidian+Teflon pellets present good conditions to be used as high dose gamma radiation detectors; the results obtained with the OSL technique were the most adequate in terms of response in function of absorbed dose. The fading of the signals, varying from about 26% (TSEE) to 44% (OSL), in a time interval of 360 h post-irradiation, also showed favorable results for the use of this material as radiation detector, when the measurements are taken after a defined time interval.

In the present work we analyzed seven globular clusters selected from their location in the Galactic bulge and with metallicity values in the range $-1.30\lesssim\rm{[Fe/H]}\lesssim-0.50$. The aim of this work is first to derive cluster ages assuming single stellar populations, and secondly, to identify the stars from first (1G) and second generations (2G) from the main sequence, subgiant and red giant branches, and to derive their age differences. Based on a combination of UV and optical filters used in this project, we apply the Gaussian mixture models to distinguish the multiple stellar populations. Applying statistical isochrone fitting, we derive self-consistent ages, distances, metallicities, and reddening values for the sample clusters. An average of $12.3\pm0.4$ Gyr was obtained both using Dartmouth and BaSTI (accounting atomic diffusion effects) isochrones, without a clear distinction between the moderately metal-poor and the more metal-rich bulge clusters, except for NGC 6717 and the inner halo NGC 6362 with $\sim 13.5$ Gyr. We derived a weighted mean age difference between the multiple populations hosted by each globular cluster of $41\pm170$ Myr adopting canonical He abundances; whereas for higher He in 2G stars, this difference reduces to $17\pm170$ Myr, but with individual uncertainties of $500$ Myr., 25 pages, 16 figures and 7 tables. Accepted for publication in ApJ

Matrizes de hidroxiapatita (HAp) dopadas com os ions lantanideos Eu3+, Ce3+ e Gd3+, [Ca10-xLnx(PO4)6(OH)2], foram obtidas pelo metodo da precipitacao com o objetivo de estudar suas propriedades fotofisicas. A partir de analises de Microscopia Eletronica de Varredura observou-se que amostras dopadas com ions lantanideos (Ln3+) apresentaram similaridade com a morfologia da HAp pura, por outro lado nos difratogramas de Raios X a partir do refinamento Rietveld verificou-se que a matriz aparece como fase majoritaria (≈ 70%) enquanto (≈ 30%) de uma fase secundaria de tricalcio fosfato (TCP) foi conferida em funcao das diferentes dopagens. Isotermas de adsorcao obtidas pela tecnica BET indicaram que todos os materiais sintetizados sao classificados como mesoporosos. Os espectros de emissao dos materiais exibem bandas caracteristicas dos ions Ln3+ incorporados a estrutura da matriz em 573 nm (5D0→F0), 600 nm (5D0→F1), 628 nm (5D0→F2), e 698 nm (5D0→F4) para HAp/Eu, 337-360 nm (5d→4f) para HAp/Ce e em 425 nm para HAp/Gd. Palavras-chave: Hidroxiapatita; Composito; Luminescente; Biomaterial; Propriedades.

Context. The interactions between the SMC and LMC created the Magellanic Bridge, a stream of gas and stars pulled out of the SMC towards the LMC about 150 Myr ago. The tidal counterpart of this structure, which should include a trailing arm, has been predicted by models but no compelling observational evidence has confirmed the Counter-Bridge so far. Aims. The main goal of this work is to find the stellar counterpart of the Magellanic Bridge and Counter-Bridge. We use star clusters in the SMC outskirts as they provide 6D phase-space vector, age and metallicity that help characterise the outskirts of the SMC. Methods. Distances, ages and photometric metallicities are derived from fitting isochrones to the colour-magnitude diagrams from the VISCACHA survey. Radial velocities and spectroscopic metallicities are derived from the spectroscopic follow-up using GMOS in the CaII triplet region. Results. Among the seven clusters analysed in this work, five belong to the Magellanic Bridge and one belongs to the Counter-Bridge and the other to the transition region. Conclusions. The existence of the tidal counterpart of the Magellanic Bridge is evidenced by star clusters. The stellar component of the Magellanic Bridge and Counter-Bridge are confirmed in the SMC outskirts. These results are an important constraint for models that seek to reconstruct the history of the orbit and interactions between LMC-SMC and constrain their future interaction including with the Milky Way., Comment: 10 pages, 7 figures. Astronomy and Astrophysics Letter, accepted. For associated video file (fig.A.4), see https://drive.google.com/file/d/1mSx3z6vDjHUneEeVq1i-MHwXZ1O0pZ-f

TiO2/ZnO hierarchical heteronanostructures were produced following a two-step procedure in which the hydrothermal growth of nanorods takes place on the surface of decorated electrospun fibers. The reaction product was a 3D-nanorod arrangement of a single-phase hexagonal wurtzite deposited onto the surface of a TiO2-decorated 1D-polymer nanoporous structure. The resulting composite was characterized as a potential candidate for photocatalytic applications, due to the available surface area and the high concentration of charge carriers, which minimizes the recombination of electrons and holes during photocatalytic processes. Photodegradation tests using rhodamine B (under visible-light irradiation) were performed to explore the photocatalytic activity of the nanostructures. Dye photodegradation ratio was determined to be 90% after 70 min, which indicates that TiO2/ZnO hierarchical heteronanostructures are potential photocatalysts.

O controle da população de cães e gatos é uma preocupaçãopara a saúde pública. Este relato descreve as atividades realizadasno Projeto de Extensão da Faculdade de Ciências Agrárias eVeterinárias da Universidade Estadual Paulista "Júlio de MesquitaFilho" (UNESP) de Jaboticabal, localizada no Estado de São Paulo,Brasil, que visou à esterilização cirúrgica de cães e gatos, comações sociais aliadas ao ensino e pesquisa. Em 2007, ano de implantaçãodo projeto, foram esterilizados 129 animais; já no anode 2014, entre os meses de janeiro e outubro, foram esterilizados1.538 animais, o que demonstra a evolução e aceitação do programapela sociedade local. Toda a atividade realizada colaboroupara a formação acadêmica e profissional dos alunos do projetode extensão, bem como residentes participantes do programa.Pode-se concluir que o desenvolvimento de programas para aesterilização de cães e gatos, em conjunto com instituições educacionais,aliando pesquisa às práticas de ensino e extensão, é umaopção viável para as práticas de ensino em Medicina Veterinária.

In this work, the response of the natural material Opal was studied in relation to its thermoluminescence (TL) and optically stimulated luminescence (OSL), after exposure to the gamma radiation of a 60 Co source. The structure of the powdered Opal was verified using the X-ray diffraction, scanning electronic microscopy and energy-dispersive X-ray spectroscopy techniques. The material, in its stone form, was turned into powder and mixed to Teflon (also in powder) in three different concentrations, and then pellets were manufactured. The aim of this work was to evaluate the response of these pellets in high-doses of gamma radiation beams, and to observe their possible application as dosimeters, using the TL and OSL techniques. The dosimetric properties of the samples were analyzed by means of different tests, as: TL emission curves and OSL signal decay curves, reproducibility of TL and OSL response, minimum detectable dose, TL and OSL dose–response curves (5 Gy–10 kGy), and fading. The results obtained in this work, for the TL and OSL phenomena, demonstrated that the pellets of Opal + Teflon present an adequate performance e possibility of use as dosimeters in beams of high-dose gamma radiation.

The Spectrolite, from the silicate family, a variety of Labradorite, was already studied in relation to its thermoluminescence (TL) and optically stimulated luminescence (OSL) responses, in high-dose gamma radiation fields; the results indicated their good application as gamma radiation detectors. In the present work, the analyses performed to investigate powdered Spectrolite are presented, by means of the XRD, SEM and EDX techniques. The luminescent behavior of Spectrolite + Teflon samples, in the concentration of 1:1, was studied in beta radiation beams (90Sr + 90Y), using the luminescent phenomena of TL and OSL. The results showed adequate TL and OSL reproducibility of the samples; the dose–response curves for both techniques presented a linear behavior in a range from 0.5 Gy to 1 kGy, and the fading showed that after 150 h there were 46.7% and 31.6% of the remaining signal of samples for TL and OSL responses, respectively. Therefore, the Spectrolite + Teflon pellets may be used in beta radiation dosimetry.

Calcium Fluoride is one of the oldest known thermoluminescent materials and is considered to be one of the most sensitive. This work presents the dosimetric properties results of CaF2:Tm produced by combustion synthesis. The X-ray diffraction confirmed that CaF2 was successfully produced. TL emission spectra, obtained using a Hammamatsu optical spectrometer, have the same lines of commercial CaF2:Tm, although transitions 3P0→3F4 (455 nm) and 1G4→3H6 (482 nm) are shown to be proportionally more intense. The deconvolution technique was employed and seven glow peaks were found similar to the commercial CaF2:Tm. A linear dose response curve was obtained for the range 0.1 mGy to 100 Gy, with the onset of a supralinear behavior at 50 Gy up to 100 Gy. The minimum measurable dose for gamma was around 100 μGy for a 6.0 mm diameter by 1.0 mm in thickness pellet. No significant fading was observed in 60 days of storage, within experimental uncertainties, showing that the main dosimetric peak is stable.

Ainda que o vidro seja um dos materiais mais antigos preparados pelo homem, ele apareceu apenas no século XX como um material que possui propriedades excelentes em áreas distintas. É um sólido amorfo com ausência de ordem a longo alcance e periodicidade, que possui transição vítrea. Pode ser obtido por várias formas, porém em grande parte é obtido pelo processo de fusão seguido do resfriamento rápido do fundido. Neste processo, a viscosidade determina as condições de fusão dos óxidos formadores do vidro, taxa de desvitrificação, etc. Este trabalho tem como objetivo avaliar a variação na viscosidade do vidro LKB (Li2CO3 – K2CO3 – H3BO3) quando adicionado óxido de alumínio (Al2O3) em diferentes proporções. A análise será efetuada utilizando o software SciGlass 7.0. Para tanto, quatro composições de vidros boratos foram desenvolvidas e estudadas. O cálculo da viscosidade em função da temperatura foi obtido para cada tipo de vidro a partir da composição dos óxidos em % mol. Resultados preliminares mostraram que a adição do óxido de alumínio aumenta a viscosidade na matriz LKB. Além disso, foi possível preparar amostras vítreas com alta transparência e homogeneidade em todos os casos a partir da correlação entre a viscosidade e a temperatura.

Nitrogen use efficiency (NUE) has implications for production performance, economic efficiency and for the emission of contaminants to the environment. Thus, the objective of this study was to evaluate whether high-concentrate diets with different levels (10 and 13% crude protein) and protein source can affect the NUE and nitrogen (N) excretion. The protein sources tested were urea, dried distillers grains (DDG) and corn gluten meal. Our hypothesis is that reducing the level of N in the diet associated with the use of rumen undegradable protein (RUP) could increase the NUE in high-concentrate diets. The hypotheses were tested using 6 cannulated Nellore steers, rumen, duodenum and ileum arranged in 6×6 Latin square designed in factorial (2 nitrogen levels and 3 protein sources) balanced for residues. The concentration of N in samples was analyzed using the Dumas combustion method. The statistical analysis was performed using the MIXED procedure of the statistical package SAS. The N intake and retention was not affected by level and protein source (P > 0.05). Fecal N excretion was not affected by the levels and protein sources tested (P > 0.05). However, there was effect of protein source (P < 0.001) and tendency to protein level in the diet (P < 0.10) on urinary N excretion. In the treatments containing the urea source, there was an increase in the urinary N excretion (46.8 g.dia-1) compared to the Gluten and DDG sources with 28.8 and 27.0 g of N excreted in the urine per day, respectively. The NUE was affected by the protein source (P < 0.05). Diets containing urea had lower NUE (31.8%) compared to corn gluten meal and DDG sources with NUE of 40.3 and 41.2%, respectively. Using RUP (DDG or Gluten) in high-concentrate diets can be a nutritional strategy for increase NUE and this response is partly attributable to decreased urinary N excretion.

This work presents the results on the Blue Stimulation Luminescence (BSL) and Infra-Red Stimulation Luminescence (IRSL) of CaF2:Tm produced by the Solution Combustion Synthesis (SCS) method. XRD confirmed the formation of calcium fluoride. BSL showed a dose independent signal due to excitation-emission of Tm bands which was not observed for IRSL. A linear dose response curves was obtained for both Blue-OSL and IR-OSL. IRSL was found approximately three times higher sensitivity than Blue-OSL. The minimum measurable dose (MMD) for BSL was found to be around 1.0 mGy. For IRSL a MMD of around 100 μGy was obtained. The results demonstrated that CaF2:Tm produced by SCS has a strong potential for OSL dosimetry.

The Distance Education is becoming more popular in today's society, involving a number of people increased, generating the need for actions in the area are accompanied by an intense reflection. In this article, we will be fomented some reflections on the use of Information and Communication Technologies and Distance Education geared to the Physics Teaching. In general talk about the motivations, conditions and possible contributions of Distance Education in Physics Teaching.

We analyse the nature of a sample of stellar overdensities that we found projected on the Carina complex. This study is based on 2MASS photometry and involves the photometry decontamination of field stars, elaboration of intrinsic colour-magnitude diagrams J$\times$(J-Ks), colour-colour diagrams (J-H)$\times$(H-Ks) and radial density profiles, in order to determine the structure and the main astrophysical parameters of the best candidates. The verification of an overdensity as an embedded cluster requires a CMD consistent with a PMS content and MS stars, if any. From these results, we are able to verify if they are, in fact, embedded clusters. The results were, in general, rewarding: in a sample of 101 overdensities, the analysis provided 15 candidates, of which three were previously catalogued as clusters (CCCP-Cl$\,$16, Treasure Chest and FSR$\,$1555), and the 12 remaining are discoveries that provided significant results, with ages not above 4.5$\,$Myr and distances compatible with the studied complex. The resulting values for the differential reddening of most candidates were relatively high, confirming that these clusters are still (partially or fully) embedded in the surrounding gas and dust, as a rule within a shell. Histograms with the distribution of the masses, ages and distances were also produced, to give an overview of the results. We conclude that all the 12 newly found embedded clusters are related to the Carina complex., 10 pages, 14 figures, accepted for publication in MNRAS

The aim of this work is to evaluate the influence of gamma radiation on a material constituted by a photonic complex used in a UV dosimetry device embedded in a polymeric composite with multiwalled carbon nanotubes (MWCNT). Films of CNT-free and MWCNT-containing composites were exposed to a gamma radiation beam of 60 Co. Characterization was performed by X-ray powder diffraction (XRD), thermogravimetric curves (TGA), and luminescence spectroscopy. The results indicate that the presented self-standing hybrid films show improvements to act as a better light conversion molecular device (LCMD) for UV dosimetry applications. Best results are attained after 50 kGy of gamma irradiation ( 60 Co) for CNT-free composites, and 5 kGy for MWCNT-containing films.

Seeking to study innovative solar cell compositions with the goal to reach the highest energy efficiency level attainable, the aim of this study was to develop a route to obtain a solar cell composed by hybrid perovskite (CH3NH3PbI3) using a sequential deposition method through the techniques of spin-coating and immersion. Initially, the deposition of PbI2 thin film of was performed on a FTO/glass substrate coated with TiO2, which was subsequently converted into perovskite crystals through spin coating using a CH3NH3I solution. The influence of the PbI2 layer thickness on the formation of CH3NH3PbI3 crystals was evaluated. The hydrophilic characteristic of TiO2 affects the distribution of the crystals nucleation sites, since PbI2 possesses a non-polar liquid characteristic. The characterization of the perovskite thin films showed that thickness affects directly the bandgap and the surface morphology, revealing the presence of dendritic structures and acicular crystals. Both growth and coverage increased for thinner layers of PbI2. It was also possible to observe an increased uniformity in the film for smaller PbI2 layers.

A experimentação é sem dúvida um dos grandes pilares da Física e uma importante forma de fomentar o processo de ensino-aprendizagem contextualizado e dinâmico. Entretanto, a experimentação por si só, sem uma reflexão profunda do fenômeno, sem dar a oportunidade do discente questioná-lo e construir a visão do mundo pode ser uma pseudo-aprendizagem. De maneira geral pontuaremos sobre as motivações, as condições e possíveis contribuições da experimentação no Ensino de Física.

Tumor growth and progression depend on angiogenesis, a process of new blood vessels formation from a preexisting vascular endothelium. Tumors promote angiogenesis by secreting or activating angiogenic factors that stimulate endothelial proliferation and migration and capillary morphogenesis. The newly formed blood vessels provide nutrients and oxygen to the tumor, increasing its growth. Thus, angiogenesis plays a key role in cancer progression and development of metastases. An important growth factor that promotes angiogenesis and participates in a variety of physiological and pathological processes is the vascular endothelial growth factor (VEGF-A or VEGF). Overexpression of VEGF results in increased angiogenesis in normal and pathological conditions. The existence of an alternative site of splicing at the 3' untranslated region of the mRNA results in the expression of isoforms with a C-terminal region which are downregulated in tumors and may have differential inhibitory effects. This suggests that control of splicing can be an important regulatory mechanism of angiogenesis in cancer.

This work examines a borate glass produced with oxides of potassium and lithium, known as LKB. The suitability of borate glasses for thermoluminescent (TL) dosimetry has been reported in previous studies. In particular, borate glasses doped with different elements showed good characteristics in terms of linearity, sensitivity and effective atomic number. However, borate glasses are also known to have high hygroscopicity, which can reduce the sensitivity of a dosimeter. Contrary to previous studies, in this work, Mg was used as one of the main components of the glass composition. Mg is known to improve the stability of the glass, since it reduces the mobility of the alkali ions and can thus reduce the hygroscopicity of the LKB glass. Three compositions containing 0, 5 and 11 mol% of magnesium oxide were examined in order to determine the effect of magnesium specifically on luminescence, high-temperature resistance and hygroscopicity of LKB glass. The LKB glass with 11 mol% of Mg showed favorable characteristics for the production of dosimeters.

Introduction Transcutaneous electrical nerve stimulation (TENS) is an established method for pain relief in dysmenorrhea. A feasible advantage would be the study of a portable device. The purpose of the study was to evaluate the effectiveness and safety of a new portable TENS device (TANYX®) for menstruation cramps. Materials and Methods Forty women were evaluated in a double-blind, prospective, randomized fashion, divided into sham and active groups. TENS was applied medially at the suprapubic region, for 30-min duration at eight-hour intervals, up to seven days. The placebo group (PG) received sham device. The TENS group (TG) applied an active 85 Hz frequency TENS. Efficacy measures were pain relief evaluated on a visual analog scale (VAS) and diclofenac intake, and quality of life represented by: 1) capacity to get out of the bed, 2) food or drink intake, 3) missing routine daily activities such as work or school, and 4) quality of sleep. Results The active TENS device induced a prompt onset of pain relief in a strictly segmental manner nearby the dermatomes where the TENS was applied at the skin, and there was a drop in mean pain score from 8 to 2 cm (p < 0.001). Diclofenac consumption was also significantly reduced (p < 0.01), compared with the PG. Quality of life improved significantly in TG when compared with PG (p < 0.05). Three months after the beginning of the study, 14/20 of the women were still using the active device regularly. No adverse effects were observed. Conclusions The portable, disposable, active TENS device induced a prompt onset of pain relief and improved the quality of life, without adverse effects, in patients with painful cramps associated with dysmenorrhea.

Aims: The ATP-binding cassette transporters, ABCA1 and ABCG1, are LXR-target genes that play an important role in reverse cholesterol transport. We examined the effects of inhibitors of the cholesterol absorption (ezetimibe) and synthesis (statins) on expression of these transporters in HepG2 cells and peripheral blood mononuclear cells (PBMCs) of individuals with primary (and nonfamilial) hypercholesterolemia (HC). Materials & methods: A total of 48 HC individuals were treated with atorvastatin (10 mg/day/4 weeks) and 23 were treated with ezetimibe (10 mg/day/4 weeks), followed by simvastatin (10 mg/day/8 weeks) and simvastatin plus ezetimibe (10 mg of each/day/4 weeks). Gene expression was examined in statin- or ezetimibe-treated and control HepG2 cells as well as PBMCs using real-time PCR. Results: In PBMCs, statins and ezetimibe downregulated ABCA1 and ABCG1 mRNA expression but did not modulate NR1H2 (LXR-β) and NR1H3 (LXR-α) levels. Positive correlations of ABCA1 with ABCG1 and of NR1H2 with NR1H3 expressions were found in all phases of the treatments. In HepG2 cells, ABCA1 mRNA levels remained unaltered while ABCG1 expression was increased by statin (1.0–10.0 µM) or ezetimibe (5.0 µM) treatments. Atorvastatin upregulated NR1H2 and NR1H3 only at 10.0 µM, meanwhile ezetimibe (1.0–5.0 µM) downregulated NR1H2 but did not change NR1H3 expression. Conclusion: Our findings reveal that lipid-lowering drugs downregulate ABCA1 and ABCG1 mRNA expression in PBMCs of HC individuals and exhibit differential effects on HepG2 cells. Moreover, they indicate that the ABCA1 and ABCG1 transcript levels were not correlated directly to LXR mRNA expression in both cell models treated with lipid-lowering drugs.

ABCA1 plays an important role in HDL metabolism. Single nucleotide polymorphisms (SNPs) in ABCA1 gene were associated with variation in plasma HDL-c.The effect of the ABCA1 SNPs C-14T, R219K and of a novel variant C-105T on serum lipids was investigated in 367 unrelated Brazilian individuals (224 hypercholesterolemic and 143 normolipidemic). The relation between ABCA1 SNPs and the lipid-lowering response to atorvastatin (10 mg/day/4 weeks) was also evaluated in 141 hypercholesterolemic (HC) individuals. The polymorphisms were detected by PCR-RFLP and confirmed by DNA sequencing.Linkage disequilibrium was found between the SNPs C-105T and C-14T in the HC group. HC individuals carrying -105CT/TT genotypes had higher serum HDL-c and lower triglyceride and VLDL-c concentrations as well as lower TG/HDL-c ratio compared to the -105CC carriers (p0.05). The R219K SNP was associated with reduced serum triglyceride, VLDL-c and TG/HDL-c ratio in the HC group (p0.05), and with an increased serum apoAI in NL individuals. The effects of ABCA1 SNPs on basal serum lipids of HC individuals were not modified by atorvastatin treatment.The ABCA1 SNPs R219K and C-105T were associated with a less atherogenic lipid profile but not with the lowering-cholesterol response to atorvastatin in a Brazilian population.

This work investigates the thermoluminescent (TL) dosimetric properties in natural spodumene, LiAlSi2O6, called kunzite, from Minas Gerais State, Brazil. The mineralogical and chemical composition of this material was identified by means X-ray fluorescence and X-ray diffraction. Some dosimetric properties were studied, such as thermoluminescent emission curves as function of gamma dose. The glow curves of annealed kunzite presented two very intense TL peaks at 215 ?C (peak II) and 350 ?C (peak III), after gamma irradiation, being both of first kinetic order. These two most prominent peaks analyzed do not presented a linear growth in the range of 50 to 5000 Gy in the range of doses studied. The peak II also presented a very short calculated lifetime, which means it is hardly can be used in dosimetry, while the peak III has a longer lifetime and could be used in some applications for high doses dosimetry.