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101.
Ana Júlia C. da Silva Fred A.R. Nogueira Odilon A.S. Araújo José Ginaldo da Silva Junior Marcelo Navarro Josealdo Tonholo Adriana S. Ribeiro 《Synthetic Metals》2009,159(21-22):2269-2272
12-Pyrrol-1′-yl dodecanoic acid was prepared and electrochemically polymerized on ITO electrodes by three different methods. The electrochemical and morphological properties of poly(12-pyrrol-1′-yl dodecanoic acid) films were investigated by cyclic voltammetry, galvanostatic charge–discharge curves and AFM, which characteristics varied as function of deposition method. Films deposited by potentiodynamic and galvanostatic methods showed capacitive properties and are promising for application in polymeric capacitors. 相似文献
102.
Although Brazil is the largest raw coffee producer and exporter in the world, a large amount of its Arabica coffee production is considered inappropriate for exportation. This by-product of coffee industry is called PVA due to the presence of black (P), green (V) and sour (A) defective beans, which are known to contribute considerably for cup quality decrease. Data on the volatile composition of Brazilian defective coffee beans are scarce. In this study, we evaluated the volatile composition of defective coffee beans (two lots) compared to good quality beans from the respective lots. Potential defective beans’ markers were identified. In the raw samples, 2-methylpyrazine and 2-furylmethanol acetate were identified only in black-immature beans and butyrolactone only in sour beans, while benzaldehyde and 2,3,5,6-tetramethylpyrazine showed to be potential markers of defective beans in general. In the roasted PVA beans, pyrazine, 2,3-butanediol meso, 2-methyl-5-(1-propenyl)pyrazine, hexanoic acid, 4-ethyl-guayacol and isopropyl p-cresol sulfide also showed to be potential defective coffee beans’ markers. 相似文献
103.
Alicia Ballester Adriana Guijarro Beatriz Bravo Javier Hernndez Rodolfo Murillas Marta I. Gallego Sara Ballester 《International journal of molecular sciences》2022,23(6)
The Hedgehog (Hh) pathway is essential for the embryonic development and homeostatic maintenance of many adult tissues and organs. It has also been associated with some functions of the innate and adaptive immune system. However, its involvement in the immune response has not been well determined. Here we study the role of Hh signalling in the modulation of the immune response by using the Ptch-1-LacZ+/− mouse model (hereinafter referred to as ptch+/−), in which the hemizygous inactivation of Patched-1, the Hh receptor gene, causes the constitutive activation of Hh response genes. The in vitro TCR stimulation of spleen and lymph node (LN) T cells showed increased levels of Th2 cytokines (IL-4 and IL-10) in ptch+/−cells compared to control cells from wild-type (wt) littermates, suggesting that the Th2 phenotype is favoured by Hh pathway activation. In addition, CD4+ cells secreted less IL-17, and the establishment of the Th1 phenotype was impaired in ptch+/− mice. Consistently, in response to an inflammatory challenge by the induction of experimental autoimmune encephalomyelitis (EAE), ptch+/− mice showed milder clinical scores and more minor spinal cord damage than wt mice. These results demonstrate a role for the Hh/ptch pathway in immune response modulation and highlight the usefulness of the ptch+/− mouse model for the study of T-cell-mediated diseases and for the search for new therapeutic strategies in inflammatory diseases. 相似文献
104.
105.
Adriana Yoshiga Luís Filipe C.P. Lima Duclerc F. Parra Rodrigo Shinzato Ademar B. Lugão 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,265(1):130-134
It is well-known that polypropylene (PP) is difficult to process as a consequence of its linear structure. It is also known that grafting of long-chain branches on PP backbone using ionizing radiation is an effective approach to achieve high melt strength polypropylene (HMS PP). Chain-scission and, in minor extend, crosslinking and grafting are the predominant reaction in order to branch PP backbone. However, if multifunctional monomers are used to promote the grafting reaction, crosslinking can surpass chain scission and grafting, reducing drawability. Therefore, in an effort to enhance the processability and so the drawability, it has been found helpful to add a small amount of polybutene-1. Gamma irradiation technique was used to induce chemical changes in blends of PP and polybutene in acetylene atmosphere (crosslinker promoter) and in HMSPP/polybutene blends. The samples were irradiated with a 60Co source with doses of 12.5 and 20 kGy in the presence of acetylene. In this work, two different methods of blends processing were compared regarding rheological and mechanical properties. Effects on the strength and elongation at the yield point and at rupture were observed by mechanical tests and showed decrease of tensile strength and increase of elongation at rupture for samples obtained by irradiation of blends. The results from rheology demonstrated an increase in melt strength and drawability of blends. 相似文献
106.
As genomes evolve over hundreds of millions years, the chromosomes become rearranged, with segments of some chromosomes inverted, while other chromosomes reciprocally exchange chunks from their ends. These rearrangements lead to the scrambling of the elements of one genome with respect to another descended from a common ancestor. Multidisciplinary work undertakes to mathematically model these processes and to develop statistical analyses and mathematical algorithms to understand the scrambling in the chromo... 相似文献
107.
In a quantitative meta-analysis, the effects of phonological awareness training on reading were shown. In a homogeneous set of U.S. studies with a randomized or matched design, the combined effect sizes for phonological awareness and reading were d?=?0.73 (r?=?.34, N?=?739) and d?=?0.70 (r?=?.33, N?=?745), respectively. Thus, experimentally manipulated phonological awareness explains about 12% of the variance in word-identification skills. The combined effect size for long-term studies of the influence of phonological awareness training on reading was much smaller, d?=?0.16 (r?=?.08, N?=?1,180). Programs combining a phonological and a letter training were more effective than a purely phonological training. Furthermore, training effects were stronger with posttests assessing simple decoding skills than with real-word-identification tests. In sum, phonological awareness is an important but not a sufficient condition for early reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
109.
Ana Paula R. Harbach Mara C.R. da Costa Adriana L. Soares Ana M. Bridi M. Shimokomaki Caio A. da Silva Elza I. Ida 《Food chemistry》2007,100(4):1630-1633
The effects of dietary defatted corn germ meal (DCGM) containing phytic acid (PA) on pig health during development and on its Longissimus dorsi m. (LD) lipid oxidative stability has been evaluated. Rations of DCGM were prepared at the level of substitution of 0%, 10%, 20% and 40% and offered to twenty four animals of Landrace x Large White crossbreds throughout 25 days before slaughtering. Animals were sacrificed at an average weight of 91.24 kg (±0.950) and samples for meat lipid oxidation analysis were taken after seven days under refrigeration at 3 °C. Animals fed with DCGM did not show any significant difference, in comparison to the control, in carcass characteristics, such as cold carcass weight, backfat depth, muscle depth, lean meat percentage and carcass dress yielding (p 0.05). Finally, no difference in meat proximate chemical composition was detected solely arising from lipid oxidation since LD from DCGM-treated pigs revealed an inhibition of 63.0%. 相似文献
110.
Ana Isabel Haza Adriana Zabala Nuria Arranz Almudena García & Paloma Morales 《International Journal of Food Science & Technology》2005,40(4):437-449
Ten strains of lactic acid bacteria were isolated from a dry fermented sausage and tested for stimulation or inhibition of the viability of Vero and myeloma cells. They did not significantly affect the viability of Vero cells but two isolates (CBL/H and CBL/K) showed a strong and moderate inhibition of the myeloma cell viability (at 108 CFU mL?1, 17.6 and 33.2%, respectively, survival of myeloma cells). The isolates were identified as Lactobacillus sakei by DNA sequencing of the 16S rRNA products of a polymerase chain reaction. No protective effect was found, at the concentrations used, against cytotoxicity of N‐nitrosamines. To test the effect of L. sakei CBL/H and CBL/K on cytokine production [tumour necrosis factor alpha (TNF‐α), interleukin‐1β (IL‐1β) and interleukin‐8 (IL‐8)], the human macrophage cell line (THP‐1) was cultured in the presence and absence of lipopolysaccharide (LPS). Lactobacillus sakei CBL/H and CBL/K induced IL‐1β and IL‐8 release when cells were stimulated with and without LPS. However there was TNF‐α release only in the presence of the LPS. 相似文献