Electrochemical and electrochromic properties of poly(4,4 dimethoxy 3'-methyl 2,2':5',2 terthiophene)

This work describes the electrochemical, spectroelectrochemical and electrochromic properties of poly(4,4 dimethoxy 3'-methyl 2,2':5',2 terthiophene) thin films. The effect of temperature on the electropolymerization was studied by cyclic voltammetry measured in situ. The temperatures used were -10, 0, 10, 20, and 40 ºC. Results indicate that the electropolymerization temperature directly affect the degree of chain organization. The optical response time for bleaching was 0.8 s and for coloring 0.3 s (for films synthesized at 40 ºC, 60 nm thick). After 1400 electrochromic cycles, the chromatic contrast at 570 nm changes from 31 to 14%. The coloration efficiency was enhanced as a function of redox cycling. This was probably caused by a decrease in the injected charge necessary for the color change, suggesting that the electroactive losses occurring during the cycles are related to sites not responsible for electrochromic contrast.Este trabalho descreve o estudo das propriedades eletroquímicas, espectroeletroquímicas e eletrocrômicas de filmes finos de poli(4,4 dimetoxi 3'-metil 2,2':5',2 tertiofeno). A voltametria cíclica in situ foi usada para estudar o efeito da temperatura sobre a eletropolimerização. As temperaturas utilizadas na deposição eletroquímica foram -10, 0, 10, 20 e 40 ºC. Os resultados indicaram que a temperatura de eletropolimerização afeta diretamente o grau de ordenamento molecular do polímero. O tempo de resposta eletrocrômico foi de 0,8 s para clareamento e 0,3 s para escurecimento (para filmes sintetizados a 40 ºC, espessura de 60 nm). Após 1400 ciclos eletrocrômicos, o contraste óptico a 570 nm diminuiu de 31 para 14%. A eficiência eletrocrômica foi intensificada em função do número de ciclos eletrocrômicos. Este fato foi provavelmente causado pela diminuição da carga injetada, necessária para a mudança de cor, sugerindo que as perdas na eletroatividade estão associadas a sítios que não são responsáveis pela mudança de coloração.733738Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Superposition effect and clan structure in forward-backward multiplicity correlations

The main purpose of this paper is to discuss the link between forward-backward multiplicity correlations properties and the shape of the corresponding final charged particle multiplicity distribution in various classes of events in different collisions. It is shown that the same mechanism which explains the shoulder effect and the H_n vs. n oscillations in charged particle multiplicity distributions, i.e., the weighted superposition of different classes of events with negative binomial properties, reproduces within experimental errors also the forward-backward multiplicity correlation strength in e+e- annihilation at LEP energy and allows interesting predictions for pp collisions in the TeV energy region, to be tested at LHC, for instance with the ALICE detector. We limit ourselves at present to study substructures properties in hadron-hadron collisions and e+e- annihilation; they are examined as ancillary examples in the conviction that their understanding might be relevant also in other more complex cases.Comment: 16 page

The structure behind the Galactic bar traced by red clump stars in the VVV survey★

Red clump stars are commonly used to map the reddening and morphology of the inner regions of the Milky Way. We use the new photometric catalogues of the VISTA Variables in the V´ıa La´ctea survey to achieve twice the spatial resolution of previous reddening maps for Galactic longitudes − 10◦ < l < 10◦ and latitudes −1.5◦ < b < 1.5◦. We use these de- reddened catalogues to construct the Ks luminosity function around the red clump in the Galactic plane. We show that the secondary peak (fainter than the red clump) detected in these regions does not correspond to the bulge red-giant branch bump alone, as previously interpreted. Instead, this fainter clump corresponds largely to the over-density of red clump stars tracing the spiral arm structure behind the Galactic bar. This result suggests that studies aiming to characterize the bulge red-giant branch bump should avoid low galactic latitudes (|b| < 2◦), where the background red clump population contributes significant contamination. It furthermore highlights the need to include this structural component in future modelling of the Galactic bar

Association Of Inflammation, Dyslipidemia, Obesity And Physical Activity Status In Children

The aim of this study was to verify the association between inflammatory biomarkers, dyslipidemia, obesity and physical activity status in 10-years old children. Ninety-four children participated in this study and were classified into eutrophic (n=36), overweight (n=34) or obese (n=24) according to their body mass index (BMI). The genic expression of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and chemokine C-C motif ligand 2 (CCL-2) mRNA; the serum concentration of high-density lipoprotein cholesterol (HDL-c) and triglycerides; BMI, percentage of body fat (% BF) and waist circumference; and the number of steps per day were determined. The expression of IL-6, TNF-α and CCL-2 were associated (p 0.05) between pro-inflammatory biomarkers and number of steps per day was found.222182

Liprobe, a vital dye for lipid aggregates detection in imaging and high-content screens

Pathological lipid accumulation is a hallmark of several metabolic disorders, and detection of lipid aggregates is an essential step for initial diagnosis and drug screening purposes. However, low-cost, simple, and reliable detection fluorescent probes are not widely available. Here, six push-pull-push dyes were studied, and proved to be highly sensitive to the polarity of the medium, presenting potential to distinguish structures with different hydrophobic indexes. Importantly, in the presence of lipid aggregates their staining specificity highly increased and the fluorescence wavelength blue shifted. One of the compounds, named Liprobe, was physiologically inert in cells, as witnessed by mass-spectrometry and metabolic assays. Liprobe was not toxic to living zebrafish embryos, and differentially stained the muscle and bone tissues. In triglyceride solutions, a high correlation was observed between Liprobe’s 558 and 592 nm emissions and the 0–2.5 mg dl−1 triglyceride range. Confocal and cell-based high content screens revealed that this fluorophore was able to selectively detect lipid droplets and ceramide loads in normal and Farber’s disease human fibroblasts, respectively. Our results demonstrate that Liprobe is a suitable fluorescing probe for vital staining of lipid aggregates, compatible with a rapid and cheap high content screening assays for preliminary diagnosis of Farber’s disease and, potentially, of other lipidosis.publishe

TNF-α mediated upregulation of Na1.7 currents in rat dorsal root ganglion neurons is independent of CRMP2 SUMOylation

Clinical and preclinical studies have shown that patients with Diabetic Neuropathy Pain (DNP) present with increased tumor necrosis factor alpha (TNF-α) serum concentration, whereas studies with diabetic animals have shown that TNF-α induces an increase in NaV1.7 sodium channel expression. This is expected to result in sensitization of nociceptor neuron terminals, and therefore the development of DNP. For further study of this mechanism, dissociated dorsal root ganglion (DRG) neurons were exposed to TNF-α for 6 h, at a concentration equivalent to that measured in STZ-induced diabetic rats that developed hyperalgesia. Tetrodotoxin sensitive (TTXs), resistant (TTXr) and total sodium current was studied in these DRG neurons. Total sodium current was also studied in DRG neurons expressing the collapsin response mediator protein 2 (CRMP2) SUMO-incompetent mutant protein (CRMP2-K374A), which causes a significant reduction in NaV1.7 membrane cell expression levels. Our results show that TNF-α exposure increased the density of the total, TTXs and TTXr sodium current in DRG neurons. Furthermore, TNF-α shifted the steady state activation and inactivation curves of the total and TTXs sodium current. DRG neurons expressing the CRMP2-K374A mutant also exhibited total sodium current increases after exposure to TNF-α, indicating that these effects were independent of SUMOylation of CRMP2. In conclusion, TNF-α sensitizes DRG neurons via augmentation of whole cell sodium current. This may underlie the pronociceptive effects of TNF-α and suggests a molecular mechanism responsible for pain hypersensitivity in diabetic neuropathy patients.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

CD81 promotes a migratory phenotype in neuronal-like cells

Tetraspanins, such as CD81, can form lateral associations with each other and with other transmembrane proteins. These interactions may underlie CD81 functions in multiple cellular processes, such as adhesion, morphology, migration, and differentiation. Since CD81's role in neuronal cells' migration has not been established, we here evaluated effects of CD81 on the migratory phenotype of SH-SY5Y neuroblastoma cells. CD81 was found enriched at SH-SY5Y cell's membrane, co-localizing with its interactor filamentous-actin (F-actin) in migratory relevant structures of the leading edge (filopodia, stress fibers, and adhesion sites). CD81 overexpression increased the number of cells with a migratory phenotype, in a potentially phosphatidylinositol 3 kinase (PI3K)-Ak strain transforming (AKT) mediated manner. Indeed, CD81 also co-localized with AKT, a CD81-interactor and actin remodeling agent, at the inner leaflet of the plasma membrane. Pharmacologic inhibition of PI3K, the canonical AKT activator, led both to a decrease in the acquisition of a migratory phenotype and to a redistribution of intracellular CD81 and F-actin into cytoplasmic agglomerates. These findings suggest that in neuronal-like cells CD81 bridges active AKT and actin, promoting the actin remodeling that leads to a motile cell morphology. Further studies on this CD81-mediated mechanism will improve our knowledge on important physiological and pathological processes such as cell migration and differentiation, and tumor metastasis.This work was supported by Fundação para a Ciência e Tecnologia (Portuguese Ministry of Science and Technology), Centro 2020 and Portugal2020, the COMPETE program, QREN, and the European Union (FEDER program) via the Institute for Biomedicine iBiMED UID/BIM/ 04501/2013, fellowship SFRH/BD/90996/2012, project PTDC/CVT-CVT/ 32261/2017, and the support of the LiM facility of iBiMED, a member of the Portuguese Platform of BioImaging (PPBI- POCI-01-0145-FEDER-022122).publishe

DIAGNÓSTICO AMBIENTAL DE DOIS CURSOS HÍDRICOS URBANOS DE GOIÂNIA COM INDICADORES BIÓTICOS

O presente diagn&oacute;stico foi realizado no munic&iacute;pio de Goi&acirc;nia em 16 de setembro de 2006 (per&iacute;odo deestiagem), onde foram demarcados 8 esta&ccedil;&otilde;es de amostragem , sendo coletados 4 pontos do C&oacute;rrego Botafogo e 4no C&oacute;rrego Samambaia, ao longo destas oito esta&ccedil;&otilde;es, mensurando algumas vari&aacute;veis f&iacute;sico-qu&iacute;micas. J&aacute; aestrutura da comunidade de insetos aqu&aacute;ticos dos referidos cursos h&iacute;dricos, foi representada por quatorze fam&iacute;liasdistribu&iacute;das nas seguintes ordens: D&iacute;ptera Ephemeroptera, Cole&oacute;ptera, Trichoptera, Odonata, Collembola,Lepidoptera e Megaloptera, com representa&ccedil;&otilde;es de cinco filos: Arthropoda, Annelida, Molusca, Crust&aacute;cea, ePlatyhelminthes. As vari&aacute;veis f&iacute;sico-qu&iacute;micas demonstraram maior comprometimento da qualidade no C&oacute;rregoBotafogo, apresentando o C&oacute;rrego Samambaia melhores condi&ccedil;&otilde;es para estes par&acirc;metros