Metallicity vs. Be phenomenon relation in the solar neighborhood

Fast rotation seems to be the mayor factor to trigger the Be phenomenon. Surface fast rotation can be favored by initial formation conditions, such as abundance of metals. We have observed 118 Be stars up to the apparent magnitudes V=9 mag. Models of fast rotating atmospheres and evolutionary tracks were used to interpret the stellar spectra and to determine the stellar fundamental parameters. Since the studied stars are formed in regions that are separated enough to imply some non negligible gradient of galactic metallicity, we study the effects of possible incidence of this gradient on the nature as rotators of the studied stars.Comment: 3 pages ; to appear in the proceedings of the Sapporo meeting on active OB stars ; ASP Conference Series ; eds: S. Stefl, S. Owocki and A. Okazak

Oil Droplet Coalescence in W/O/W Double Emulsions Examined in Models from Micrometer-to Millimeter-Sized Droplets

Water-in-oil-in-water (W$_{1}$/O/W$_{2}$) double emulsions must resist W$_{1}$–W$_{1}$, O–O and W$_{1}$–W$_{2}$ coalescence to be suitable for applications. This work isolates the stability of the oil droplets in a double emulsion, focusing on the impact of the concentration of the hydrophilic surfactant. The stability against coalescence was measured on droplets ranging in size from millimeters to micrometers, evaluating three different measurement methods. The time between the contact and coalescence of millimeter-sized droplets at a planar interface was compared to the number of coalescence events in a microfluidic emulsion and to the change in the droplet size distributions of micrometer-sized single and double emulsions. For the examined formulations, the same stability trends were found in all three droplet sizes. When the concentration of the hydrophilic surfactant is reduced drastically, lipophilic surfactants can help to increase the oil droplets’ stability against coalescence. This article also provides recommendations as to which purpose each of the model experiments is suited and discusses advantages and limitations compared to previous research carried out directly on double emulsions

The dependence of the viscosity-parameter on the disk scale height profile

It is shown that the height scale for accretion disks is a constant whenever hydrostatic equilibrium and sub-sonic turbulence regime hold in the disk. In order to have a variable height scale, processes that do contribute with an extra term to the continuity equation are needed. This makes the viscosity parameter much greater in the outer region and much smaller in the inner region. Under these circumstances, turbulence is a presumable source of viscosity in the disk.Comment: 8 pages, submitted to Apj

Achernar: Rapid Polarization Variability as Evidence of Photospheric and Circumstellar Activity

We present the results of a high accuracy ($\sigma \approx 0.005$) polarization monitoring of the Be Star Achernar that was carried out between July 7th and November 5th, 2006. Our results indicate that, after a near quiescent phase from 1998 to 2002, Achernar is presently in an active phase and has built a circumstellar disk. We detect variations both in the polarization level and position angle in timescales as short as one hour and as long as several weeks. Detailed modeling of the observed polarization strongly suggests that the short-term variations originate from discrete mass ejection events which produce transient inhomogeneities in the inner disk. Long-term variations, on the other hand, can be explained by the formation of an inner ring following one or several mass ejection events.Comment: 16 pages, 5 figures, Accepted to Ap

Perineal care and outcomes in a birth center

Objective: to analyse the perineal outcomes in childbirth and post-partum perineal care in a freestanding birth centre. Method: a cross-sectional study, with data collection performed in the women’s birth records forms from Casa Angela, a freestanding birth centre, São Paulo, Brazil, in 2016-2017 (n=415). The following data was analysed: occurrence and perineal tear degree; maternal, neonatal and birth care-related variables; perineal suture prevalence; complications in wound healing and natural methods on perineal care. Data were subjected to descriptive, inferential and multiple analyses. Results: in 11.8% of women, the perineum was kept intact, 61.9% had spontaneous first-degree tear and 26.3% had second-degree tear. The variables related to the occurrence and higher spontaneous degree tears were maternal age and second period of childbirth >2 hours. The protective factors against the occurrence and higher degree tears were number of previous vaginal childbirths and maternal position different from vertical during childbirth. Perineal suture was performed in 16.0% and 70.6% of women with spontaneous first- and second-degree tears, respectively. The main perineal complications after birth were edema (53.6%) and pain (29.4%); and the perineal suture increased the chance for these complications (OR=2.5; 95%CI 1.5-4.3). Perineum icepack compress was used in 53.8% of women during post-partum period. Conclusion: maternal and health-care related factors were associated to the prevalence and degree of spontaneous perineal tear. First-degree spontaneous perineal tears were prevalent and sutured in a low number of women. There were more complications in the wound healing process when the perineal suture was performed, regardless the tear degree. The number of natural methods in post-partum perineal care was higher than the use of medicines

Evolution of the circumstellar disc of alpha Eri

The Halpha line emission formation region in the circumstellar disc of alpha Eri is: a) extended with a steep outward matter density decline during low H$\alpha$ emission phases; b) less extended with rather constant density distribution during the strong Halpha emission. The long-term variation of the Halpha emission has a 14-15 year cyclic B-Be phase transition. The disc formation time scales agree with the viscous decretion model. The time required for the disc dissipation is longer than expected from the viscous disc model.Comment: 3 pages ; to appear in the proceedings of the Sapporo meeting on active OB stars ; ASP Conference Series ; eds: S. Stefl, S. Owocki and A. Okazak

Relevance of Translational Regulation on Plant Growth and Environmental Responses

The authors acknowledge funding by MINECO BIO2015-70483-R to AF, by CAM S2013/ABI-2734 and by ERC GA260468 to MMC, by the Deutsche Forschungsgemeinschaft (DFG, grant TRR175-C05) to DL, by NSF IOS 1444561 and NSF IOS PAPM-EAGER 1650139 to AS, and by Bio4Energy, a Strategic Research Environment appointed by the Swedish government to JH.Ferrando Monleón, AR.; Castellano, M.; Lisón, P.; Leister, D.; Stepanova, AN.; Hanson, J. (2017). Relevance of Translational Regulation on Plant Growth and Environmental Responses. Frontiers in Plant Science. 8:1-2. https://doi.org/10.3389/fpls.2017.02170S128Hummel, M., Cordewener, J. H. G., de Groot, J. C. M., Smeekens, S., America, A. H. P., & Hanson, J. (2012). Dynamic protein composition of Arabidopsis thaliana cytosolic ribosomes in response to sucrose feeding as revealed by label free MSE proteomics. PROTEOMICS, 12(7), 1024-1038. doi:10.1002/pmic.201100413Vermeulen, S. J., Campbell, B. M., & Ingram, J. S. I. (2012). Climate Change and Food Systems. Annual Review of Environment and Resources, 37(1), 195-222. doi:10.1146/annurev-environ-020411-130608Vogel, C., & Marcotte, E. M. (2012). Insights into the regulation of protein abundance from proteomic and transcriptomic analyses. Nature Reviews Genetics, 13(4), 227-232. doi:10.1038/nrg318