1,365 research outputs found
Faint emission lines in the Galactic H II regions M16, M20 and NGC 3603
We present deep echelle spectrophotometry of the Galactic {\hii} regions M16,
M20 and NGC 3603. The data have been taken with the Very Large Telescope
Ultraviolet-Visual Echelle Spectrograph in the 3100 to 10400 \AA range. We have
detected more than 200 emission lines in each region. Physical conditions have
been derived using different continuum and line intensity ratios. We have
derived He, C and O abundances from pure recombination
lines as well as abundances from collisionally excited lines for a large number
of ions of different elements. We have obtained consistent estimations of the
temperature fluctuation parameter, {\ts}, using different methods. We also
report the detection of deuterium Balmer lines up to D (M16) and to
D (M20) in the blue wings of the hydrogen lines, which excitation
mechanism seems to be continuum fluorescence. The temperature fluctuations
paradigm agree with the results obtained from optical CELs and the more
uncertain ones from far IR fine structure CELs in NGC 3603, although, more
observations covering the same volume of the nebula are necessary to obtain
solid conclusions.Comment: 22 pages, 13 Tables, 7 Figures. Accepted for publication by MNRA
465 MESENCHYMAL STEM CELLS IN TYPE I COLLAGEN VEHICLES AS AN ADDITIONAL TREATMENT FOR ROTATOR CUFF TEARS: A RAT EXPERIMENTAL MODEL
"Feeding Fats Safety" Project. Improving the use of feeding fats materials coming from byor co-products from the food chain : a quality and safety approach
Ancestry-related assortative mating in Latino populations
Examination of ancestry-informative genetic markers shows that Puerto Rican and Mexican populations have shown strong assortative mating that continues to this day
Chemical abundances of the Galactic H II region NGC 3576 derived from VLT echelle spectrophotometry
We present echelle spectrophotometry of the Galactic H II region NGC 3576.
The data have been taken with the VLT UVES echelle spectrograph in the 3100 to
10400 angstroms range. We have measured the intensities of 458 emission lines,
344 are permitted lines of H0, He0, C+, N0, N+, N++, O0, O+, Ne+, S++, Si0,
Si+, Ar0 and Ar+; some of them are produced by recombination and others mainly
by fluorescence. Electron temperatures and densities have been determined using
different continuum and line intensity ratios. We have derived He+, C++, O+,
O++ and Ne++ ionic abundances from pure recombination lines. We have also
derived abundances from collisionally excited lines for a large number of ions
of different elements. Remarkably consistent estimations of t2 have been
obtained by comparing Balmer and Paschen to [O III] temperatures, and O++ and
Ne++ ionic abundances obtained from collisionally excited and recombination
lines. The chemical composition of NGC 3576 is compared with those of other
Galactic H II regions and with the one from the Sun. A first approach to the
gas-phase Galactic radial abundance gradient of C as well as of the C/O ratio
has been made.Comment: 25 pages, 14 tables, 4 figures. Accepted for publication in ApJ
Optical Recombination Lines of Heavy-elements in Giant Extragalactic HII Regions
We present high resolution observations of the giant extragalactic H II
regions NGC 604, NGC 2363, NGC 5461 and NGC 5471, based on observations taken
with the ISIS spectrograph on the William Herschel Telescope. We have detected
-by the first time- C II and O II recombination lines in these objects. We find
that recombination lines give larger C^{++} and O^{++} abundances than
collisionallly excited lines, suggesting that temperature variations can be
present in the objects. We detect [Fe IV] lines in NGC 2363 and NGC 5471, the
most confident detection of optical lines of this kind in H II regions.
Considering the temperature structure we derive their H, He, C, N, O, Ne, S,
Ar, and Fe abundances. From the recombination lines of NGC 5461 and NGC 5471 we
determine the presence of C/H and O/H gradients in M101. We calculate the Delta
Y/Delta O and Delta Y/Delta Z values considering the presence of temperature
variations and under the assumption of constant temperature. We obtain a better
agreement with models of galactic chemical evolution by considering the
presence of temperature variations than by assuming that the temperature is
constant in these nebulae.Comment: 42 pages, 5 figures. To be published in Ap
Virus infection elevates transcriptional activity of miR164a promoter in plants
Background: Micro RNAs (miRs) constitute a large group of endogenous small RNAs that have crucial roles in many important plant functions. Virus infection and transgenic expression of viral proteins alter accumulation and activity of miRs and so far, most of the published evidence involves post-transcriptional regulations.
Results: Using transgenic plants expressing a reporter gene under the promoter region of a characterized miR (P-miR164a), we monitored the reporter gene expression in different tissues and during Arabidopsis development. Strong expression was detected in both vascular tissues and hydathodes. P-miR164a activity was developmentally regulated in plants with a maximum expression at stages 1.12 to 5.1 (according to Boyes, 2001) along the transition from vegetative to reproductive growth. Upon quantification of P-miR164a-derived GUS activity after Tobacco mosaic virus Cg or Oilseed rape mosaic virus (ORMV) infection and after hormone treatments, we demonstrated that ORMV and gibberellic acid elevated P-miR164a activity. Accordingly, total mature miR164, precursor of miR164a and CUC1 mRNA (a miR164 target) levels increased after virus infection and interestingly the most severe virus (ORMV) produced the strongest promoter induction.
Conclusion: This work shows for the first time that the alteration of miR pathways produced by viral infections possesses a transcriptional component. In addition, the degree of miR alteration correlates with virus severity since a more severe virus produces a stronger P-miR164a induction.Instituto de BiotecnologíaFil: Bazzini, Ariel Alejandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Almasia, Natalia Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Manacorda, Carlos Augusto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Mongelli, Vanesa Claudia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Conti, Gabriela. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Maroniche, Guillermo Andrés. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rodriguez, Maria Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Distefano, Ana Julia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Del Vas, Mariana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Asurmendi, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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Expression of SMARCD1 interacts with age in association with asthma control on inhaled corticosteroid therapy.
BackgroundGlobal gene expression levels are known to be highly dependent upon gross demographic features including age, yet identification of age-related genomic indicators has yet to be comprehensively undertaken in a disease and treatment-specific context.MethodsWe used gene expression data from CD4+ lymphocytes in the Asthma BioRepository for Integrative Genomic Exploration (Asthma BRIDGE), an open-access collection of subjects participating in genetic studies of asthma with available gene expression data. Replication population participants were Puerto Rico islanders recruited as part of the ongoing Genes environments & Admixture in Latino Americans (GALA II), who provided nasal brushings for transcript sequencing. The main outcome measure was chronic asthma control as derived by questionnaires. Genomic associations were performed using regression of chronic asthma control score on gene expression with age in years as a covariate, including a multiplicative interaction term for gene expression times age.ResultsThe SMARCD1 gene (SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily D member 1) interacted with age to influence chronic asthma control on inhaled corticosteroids, with a doubling of expression leading to an increase of 1.3 units of chronic asthma control per year (95% CI [0.86, 1.74], p = 6 × 10- 9), suggesting worsening asthma control with increasing age. This result replicated in GALA II (p = 3.8 × 10- 8). Cellular assays confirmed the role of SMARCD1 in glucocorticoid response in airway epithelial cells.ConclusionFocusing on age-dependent factors may help identify novel indicators of asthma medication response. Age appears to modulate the effect of SMARCD1 on asthma control with inhaled corticosteroids
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