Photometry and dynamics of the minor mergers AM\,1228-260 and AM\,2058-381

We investigate interaction effects on the dynamics and morphology of the galaxy pairs AM\,2058-381 and AM\,1228-260. This work is based on $r'$ images and long-slit spectra obtained with the Gemini Multi-Object Spectrograph at the Gemini South Telescope. The luminosity ratio between the main (AM\,2058A) and secondary (AM\,2058B) components of the first pair is a factor of $\sim$ 5, while for the other pair, the main (AM\,1228A) component is 20 times more luminous than the secondary (AM\,1228B). The four galaxies have pseudo-bulges, with a S\'ersic index $n<2$. Their observed radial velocities profiles (RVPs) present several irregularities. The receding side of the RVP of AM\,2058A is displaced with respect to the velocity field model, while there is a strong evidence that AM\,2058B is a tumbling body, rotating along its major axis. The RVPs for AM\,1228A indicate a misalignment between the kinematic and photometric major axes. The RVP for AM\,1228B is quite perturbed, very likely due to the interaction with AM\,1228A. NFW halo parameters for AM\,2058A are similar to those of the Milky Way and M\,31. The halo mass of AM\,1228A is roughly 10\% that of AM\,2058A. The mass-to-light (M/L) of AM\,2058 agrees with the mean value derived for late-type spirals, while the low M/L for AM\,1228A may be due to the intense star formation ongoing in this galaxy.Comment: 20 pages, 10 figures, accepted for publication in MNRA

Expérience vécue par les parents lors de l'hospitalisation d'un très grand prématuré de moins de 28 semaines: revue de littérature étoffée

Un très grand prématuré de moins de 28 semaines hospitalisé en néonatologie présente de nombreuses complications liées à son immaturité. De plus, les risques de séquelles sévères qu’il pourra présenter dans sa vie future, ainsi que le risque de décès ne sont pas à négliger. Les parents sont donc confrontés à des moments très angoissants durant cette hospitalisation. Pour offrir à ces parents un accompagnement adéquat, l’infirmière devra explorer leur expérience face à cette situation

Impact of soil warming and shading on colonization and community structure of arbuscular mycorrhizal fungi in roots of a native grassland

Arbuscular mycorrhizal (AM) fungi have a major influence on the structure, responses and below-ground C allocation of plant communities. Our lack of understanding of the response of AM fungi to factors such as light and temperature is an obstacle to accurate prediction of the impact of global climate change on ecosystem functioning. In order to investigate this response, we divided a grassland site into 24 plots, each either unshaded or partly shaded with soil either unheated or heated by 3°C at 2 cm depth. In both short-term studies in spring and autumn, and in a 1-year-long study, we measured root length colonization (LRC) by AM and non-AM fungi. For selected root samples, DNA sequences were amplified by PCR with fungal-specific primers for part of the small sub-unit (SSU) rRNA gene. In spring, the total LRC increased over 6 weeks from 12% to 25%. Shading significantly reduced AM but increased non-AM fungal colonization, while soil warming had no effect. In the year-long study, colonization by AM fungi peaked in summer, whereas non-AM colonization peaked in autumn, when there was an additive effect of shading and soil warming that reduced AM but increased non-AM fungi. Stepwise regression revealed that light received within the 7 days prior to sampling was the most significant factor in determining AM LRC and that mean temperature was the most important influence on non-AM LRC. Loglinear analysis confirmed that there were no seasonal or treatment effects on the host plant community. Ten AM fungal sequence types were identified that clustered into two families of the Glomales, Glomaceae and Gigasporaceae. Three other sequence types were of non-AM fungi, all Ascomycotina. AM sequence types showed seasonal variation and shading impacts: loglinear regression analysis revealed changes in the AM fungal community with time, and a reduction of one Glomus sp. under shade, which corresponded to a decrease in the abundance of Trifolium repens. We suggest that further research investigating any impacts of climate change on ecosystem functioning must not only incorporate their natural AM fungal communities but should also focus on niche separation and community dynamics of AM fungi

On the Implementation of AM/AM AM/PM Behavioral Models in System Level Simulation

The use of nonlinear device behavioral models offers an economical way of simulating the performance of complex communication systems. A concrete method for implementing the AM/AM AM/PM behavioral model in system level simulation using ADS is developed. This method seamlessly tansfers the data from the circuit level simulation to system level simulation, where the AM/AM AM/PM model is automatically built. The methodology is extendible for use in other software packages or between different software packages

The variation in transparency of amniotic membrane used in ocular surface regeneration

Background/aims: Scant consideration has been given to the variation in structure of the human amniotic membrane (AM) at source or to the significance such differences might have on its clinical transparency. Therefore, we applied our experience of quantifying corneal transparency to AM. Methods: Following elective caesarean, AM from areas of the fetal sac distal and proximal (ie, adjacent) to the placenta was compared with freeze-dried AM. The transmission of light through the AM samples was quantified spectrophotometrically; also, tissue thickness was measured by light microscopy and refractive index by refractometry. Results: Freeze-dried and freeze-thawed AM samples distal and proximal to the placenta differed significantly in thickness, percentage transmission of visible light and refractive index. The thinnest tissue (freeze-dried AM) had the highest transmission spectra. The thickest tissue (freeze-thawed AM proximal to the placenta) had the highest refractive index. Using the direct summation of fields method to predict transparency from an equivalent thickness of corneal tissue, AM was found to be up to 85% as transparent as human cornea. Conclusion: When preparing AM for ocular surface reconstruction within the visual field, consideration should be given to its original location from within the fetal sac and its method of preservation, as either can influence corneal transparency