Global helioseismology (WP4.1): From the Sun to the stars & solar analogs

Sun-as-a star observations put our star as a reference for stellar observations. Here, I review the activities in which the SPACEINN global seismology team (Working Package WP4.1) has worked during the past 3 years. In particular, we will explain the new deliverables available on the SPACEINN seismic+ portal. Moreover, special attention will be given to surface dynamics (rotation and magnetic fields). After characterizing the rotation and the magnetic properties of around 300 solar-like stars and defining proper metrics for that, we use their seismic properties to characterize 18 solar analogues for which we study their surface magnetic and seismic properties. This allows us to put the Sun into context compared to its siblings.Comment: Proceedings of the SPACEINN/TASC2/KASC9 meeting. 7 pages, 6 figure

Mode visibilities in radial velocity and intensity Sun-as-a-star helioseismic measurements

We analyze more than 5000 days of Sun-as-a-star radial velocity GOLF and intensity VIRGO observations to measure the visibilities of the l=0, 1, 2, and 3 modes and the m-amplitude ratios of the l=2 and 3 modes in the solar acoustic spectrum. We provide observational values that we compare to theoretical predictions.Comment: SOHO 24 / GONG 2010 conference, to be published in JPC

In vitro identification and in silico utilization of interspecies sequence similarities using GeneChip(® )technology

BACKGROUND: Genomic approaches in large animal models (canine, ovine etc) are challenging due to insufficient genomic information for these species and the lack of availability of corresponding microarray platforms. To address this problem, we speculated that conserved interspecies genetic sequences can be experimentally detected by cross-species hybridization. The Affymetrix platform probe redundancy offers flexibility in selecting individual probes with high sequence similarities between related species for gene expression analysis. RESULTS: Gene expression profiles of 40 canine samples were generated using the human HG-U133A GeneChip (U133A). Due to interspecies genetic differences, only 14 ± 2% of canine transcripts were detected by U133A probe sets whereas profiling of 40 human samples detected 49 ± 6% of human transcripts. However, when these probe sets were deconstructed into individual probes and examined performance of each probe, we found that 47% of human probes were able to find their targets in canine tissues and generate a detectable hybridization signal. Therefore, we restricted gene expression analysis to these probes and observed the 60% increase in the number of identified canine transcripts. These results were validated by comparison of transcripts identified by our restricted analysis of cross-species hybridization with transcripts identified by hybridization of total lung canine mRNA to new Affymetrix Canine GeneChip(®). CONCLUSION: The experimental identification and restriction of gene expression analysis to probes with detectable hybridization signal drastically increases transcript detection of canine-human hybridization suggesting the possibility of broad utilization of cross-hybridizations of related species using GeneChip technology

CoRoT reveals a magnetic activity cycle in a Sun-like star

The 11-year activity cycle of the Sun is a consequence of a dynamo process occurring beneath its surface. We analyzed photometric data obtained by the CoRoT space mission, showing solar-like oscillations in the star HD49933, for signatures of stellar magnetic activity. Asteroseismic measurements of global changes in the oscillation frequencies and mode amplitudes reveal a modulation of at least 120 days, with the minimum frequency shift corresponding to maximum amplitude as in the Sun. These observations are evidence of a stellar magnetic activity cycle taking place beneath the surface of HD49933 and provide constraints for stellar dynamo models under conditions different from those of the Sun.Comment: Brevia text and supporting online material, published in Scienc

Poly(lactic acid) formulations with improved toughness by physical blending with thermoplastic starch

This is the peer reviewed version of the following article: Ferri, J.M., Garcia-Garcia, D., Carbonell-Verdu, A., Fenollar, Octavio, Balart, Rafael. (2018). Poly(lactic acid) formulations with improved toughness by physical blending with thermoplastic starch.Journal of Applied Polymer Science, 135, 4, 45751-. DOI: 10.1002/app.45751, which has been published in final form at http://doi.org/10.1002/app.45751. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] This work focuses on poly(lactic acid) (PLA) formulations with improved toughness by physical blending with thermoplastic maize starch (TPS) plasticized with aliphatic¿aromatic copolyester up to 30 wt %. A noticeable increase in toughness is observed, due to the finely dispersed spherical TPS domains in the PLA matrix. It is worth to note the remarkable increase in the elongation at break that changes from 7% (neat PLA) up to 21.5% for PLA with 30 wt % TPS. The impact-absorbed energy is markedly improved from the relatively low values of neat PLA (1.6 J/m2) up to more than three times. Although TPS is less thermally stable than PLA due to its plasticizer content, in general, PLA/TPS blends offer good balanced thermal stability. The morphology reveals high immiscibility in PLA/TPS blends, with TPS-rich domains with an average size of 1 micrometre, finely dispersed which, in turn, is responsible for the improved toughness.Authors thank the Ministry of Economy and Competitiveness (MINECO), Ref.: MAT2014–59242-C2-1-R for their support. Authors also thank “Conselleria d’Educacio, Cultura i Esport”- Generalitat Valenciana, Ref.: GV/2014/008 for financial support.Ferri, J.; Garcia-Garcia, D.; Carbonell-Verdu, A.; Fenollar, O.; Balart, R. (2018). Poly(lactic acid) formulations with improved toughness by physical blending with thermoplastic starch. Journal of Applied Polymer Science. 135(4). https://doi.org/10.1002/app.45751S45751135