Ostreococcus tauri, a unicellular marine green alga, is the smallest known free-living eukaryote and is ubiquitous in the surface oceans. The ecological success of this organism has been attributed to distinct low- and high-light-adapted ecotypes existing in different niches at a range of depths in the ocean. Viruses have already been characterized that infect the high-light-adapted strains. Os...

Context. Mass accretion rate determinations are fundamental for an understanding of the evolution of pre-main sequence star circumstellar disks. Aims. Magnetospheric accretion models are used to derive values of the mass accretion rates in objects of very different properties, from brown dwarfs to intermediate-mass stars; we test the validity of these models in the brown dwarf regime, where the...

We present low-resolution spectra collected with the Spectral Energy Distribution Machine (SEDM) for an IW And-type dwarf nova, HO Puppis, and a Be star, V722 Tauri. The SEDM is integrated field unit spectrograph mounted on 60 inch telescope at Palomar Observatory, spectral resolution of R ∼ 100 in optical wavelength range. Hα emission line was clearly detected bright star Tauri ∼12.5 mag, but ...

We investigate the evolution of circumstellar discs around T Tauri stars that are ejected from small stellar clusters within molecular clouds. In particular, we study how the interaction that leads to ejection may hasten the transition between Classical and Weak-lined T Tauri status. In our models, ejections of T Tauri stars at velocities of 3-10 km/s truncate the accretion disc at radii betwee...

The circadian clock measures time across a 24 h period, increasing fitness by phasing biological processes to the most appropriate time of day. The interlocking feedback loop mechanism of the clock is conserved across species; however, the number of loops varies. Mathematical and computational analyses have suggested that loop complexity affects the overall flexibility of the oscillator, includ...

This paper describes the first optical spectroscopic survey of class I sources (also known as embedded sources and protostars) in the Taurus-Auriga dark cloud. We detect 10 of the 24 known class I sources in the cloud at 5500–9000 Å. All detected class I sources have strong Hα emission; most also have strong [O I] and [S II] emission. These data – together with high quality optical spectra of T...

three grass species, agropyron desertorum (agde) and agropyron elongatum (agel) and recently, bromus tomentellus (brto) are mainly used for range improvement as mixed seeding in semi-arid areas of iran. because there is little information about management of these grasses, this study was conducted at the sisab research station in northern iran to evaluate their responses to grazing management a...