971 resultados para 004.19 Elaboratori ibridi e analogici
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Cell adhesion molecules (CAMs) are surface receptors present in eukaryotic cells that mediate cell-cell or cell-extracellular matrix interactions. Vascular endothelium stimulation in vitro that lead to the upregulation of CAMs was reported for the pathogenic spirochaetes, including rLIC10365 of Leptospira interrogans. In this study, we report the cloning of LIC10507, LIC10508, LIC10509 genes of L interrogans using Escherichia coli as a host system. The rational for selecting these sequences is due to their location in L. interrogans serovar Copenhageni genome that has a potential involvement in pathogenesis. The genes encode for predicted lipoproteins with no assigned functions. The purified recombinant proteins were capable to promote the upregulation of intercellular adhesion molecule 1 (ICAM-1) and E-selectin on monolayers of human umbilical vein endothelial cells (HUVECS). In addition, the coding sequences are expressed in the renal tubules of animal during bacterial experimental infection. The proteins are probably located at the outer membrane of the bacteria since they are detected in detergent-phase of L interrogans Triton X-114 extract. Altogether our data suggest a possible involvement of these proteins during bacterial infection and provide new insights into the role of this region in the pathogenesis of Leptospira. (C) 2008 Elsevier Ltd. All rights reserved.
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A method is developed to search for air showers initiated by photons using data recorded by the surface detector of the Auger Observatory. The approach is based on observables sensitive to the longitudinal shower development, the signal risetime and the curvature of the shower front. Applying this method to the data, tipper limits on the flux of photons of 3.8 x 10(-3), 2.5 x 10(-3), and 2.2 x 10(-3) km(-2) sr(-1) yr(-1) above 10(19) eV, 2 x 10(19) eV, and 4 x 10(19) eV are derived, with corresponding limits on the fraction of photons being 2.0%, 5.1%, and 31% (all limits at 95% c.l.). These photon limits disfavor certain exotic models of sources of cosmic rays. The results also show that the approach adopted by the Auger Observatory to calibrate the shower energy is not strongly biased by a contamination from photons. (C) 2008 Elsevier B.V. All rights reserved.
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Terbium (Tb) doped LaMgAl(11)O(19) phosphors have been prepared by the combustion of corresponding metal nitrates (oxidizer) and urea (fuel) at furnace temperature as low as 500 C Combustion synthesized powder phosphor was characterized by X-ray diffraction and field emission scanning electron microscopy techniques LaMgAl(11)O(19) doped with trivalent terbium ions emit weakly in blue and orange light region and strongly in green light region when excited by the ultraviolet light of 261 nm Electron Spin Resonance (ESR) studies were carried out to study the defect centres Induced in the phosphor by gamma irradiation and also to identify the defect centres responsible for the thermally stimulated luminescence (TSL) process Room temperature ESR spectrum of irradiated phosphor appears to be a superposition of at least two defect centres One of the centres (centre I) with principal g-values g(parallel to) = 2 0417 and g(perpendicular to) = 2 0041 is identified as O(2)(-) ion while centre II with an axially symmetric g-tensor with principal values g(parallel to) = 19698 and g(perpendicular to) = 1 9653 is assigned to an F(+) centre (singly ionized oxygen vacancy) An additional defect centre is observed during thermal annealing experiments and this centre (assigned to F(+) centre) seems to originate from an F centre (oxygen vacancy with two electrons) The F centre and also the F+ centre appear to correlate with the observed high temperature TSL peak in LaMgAl(11)O(19) Tb phosphor (C) 2010 Elsevier Masson SAS All rights reserved
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Phytase (myo-inositol hexaphosphate phosphohydrolase) and phytic acid (myo-inositol hexaphosphate) play an important environmental role, in addition to being a health issue in food industry. Phytic acid is antinutritional due to its ability to chelate metal ions and may also react with proteins decreasing their bioavailability. In this work, we produced biosensors with phytase immobilized in Layer-by-Layer (LbL) films, which could detect phytic acid with a detection limit of 0.19 mmol L-1, which is sufficient to detect phytic acid in seeds of grains and vegetables. The biosensosrs consisted of LbL films containing up to eight bilayers of phytase alternated with poly(allylamine) hydrochloride (PAH) deposited onto an indium-tin oxide (ITO) substrate modified with Prussian Blue. Amperometric detection was conducted in an acetate buffer solution (at pH 5.5) at room temperature, with the biosensor response attributed to the formation of phosphate ions. In subsidiary experiments with the currents measured at 0.0 V (vs. SCE), we demonstrated the absence of effects from some interferents, pointing to a good selectivity of the biosensor. (c) 2007 Elsevier B.V. All rights reserved.
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Previous analysis of the ECD spectra of two prenylated benzopyrans isolated from Peperomia obtusifolia, by means of the helicity rule for the chromane chromophore, resulted in the incorrect assignment of their absolute configuration, (5) instead of (R) for a deduced P-helicity of the chromane ring for the (+)-enantiomers. This was discovered by the application of DFT calculations and VCD spectroscopy. Experimental and calculated (B3LYP/6-31G(d)) VCD and IR spectra were compared, and a definitive absolute configuration of (+)-1 and (+)-2 is reassigned directly in solution as (R). The assumption of equatorial positioning of bulky groups, shown here to be invalid for the title molecules, is the underlying cause of the previous incorrect assignment of absolute configuration. Moreover, TDDFT (B3LYP/6-311++G(2d,2p)//B3LYP/6-31G(d)) calculations of ECD spectra have shown that both P- and M-helicity of the heterocyclic ring, for a given absolute configuration, lead to the same sign for the (1)L(b) ECD band, thus bringing into question the validity of the empirical ECD helicity rule for chromane molecules. (C) 2010 Elsevier Ltd. All rights reserved.
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Some themes discussed are: • Jewish education—Hebrew tutor/Hebrew school(1) • Jewish education—Sunday School(10) • Jewish education—parents (12) • Holidays (1-2) • Civic engagement (1, 5) • Civic engagement—B’nai B’rith and Hadassah (2) • Food—kosher (2) • Colby—Greek life (3-4) • Occupation—law (4) • Dating—marriage (5) • Dating—at Colby (8) • Dating—interfaith marriage (9) • Live in Waterville—attractions (6) • Live in Waterville—school (9) • Colby—Hillel (6) • Colby—classes (6) • Colby—campus life (7-8, 12-13) • Synagogue (11)
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Some themes discussed are: • Jewish identity—prayer (1, 3) • Jewish identity—modern changes (3) • Jewish education—Hebrew/Sunday School (1, 4, 5) • Food—family picnics (2) • Food—favorites (13) • Food—kosher (14) • Occupation—store/tailoring (2) • Occupation—law (8-9) • Occupation—legislature (8-9) • Education—Bowdoin (8) • Education—Harvard Law (8) • Marriage—parents (9-10) • Intermarriage (11) • Social life—Center Youth (11) • Dating—non-Jews (12)
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Fiorello's Flute is the official student newspaper of LaGuardia Community College. It is published by an independent student staff and financed by student activity funds. Opinions expressed in the paper are not necessarily those of the College administration, faculty, or the student body. Editorial opinion expressed herein is determined by a majority vote of the Flute staff.
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PRINT NO: 74
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Print Number 77
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Initials Lower Right: ELW (Everett Longley Warner)
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http://digitalcommons.risd.edu/dazzleprints/1111/thumbnail.jpg
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Print No. 66