Structure and dynamics of the supercluster of galaxies SC0028-0005

According to the standard cosmological scenario, superclusters are objects that have just passed the turn around point and are collapsing. The dynamics of very few superclusters have been analysed up to now. In this paper we study the supercluster SC0028-0005, at redshift 0.22, identify the most prominent groups and/or clusters that make up the supercluster, and investigate the dynamic state of this structure. For the membership identification, we have used photometric and spectroscopic data from SDSS-DR10, finding 6 main structures in a flat spatial distribution. We have also used a deep multi-band observation with MegaCam/CFHT to estimate de mass distribution through the weak-lensing effect. For the dynamical analysis, we have determined the relative distances along the line of sight within the supercluster using the Fundamental Plane of early-type galaxies. Finally, we have computed the peculiar velocities of each of the main structures. The 3D distribution suggests that SC0028-005 is indeed a collapsing supercluster, supporting the formation scenario of these structures. Using the spherical collapse model, we estimate that the mass within $r = 10$~Mpc should lie between 4 and $16 \times 10^{15} M_\odot$. The farthest detected members of the supercluster suggest that within $\sim 60$~Mpc the density contrast is $\delta \sim 3$ with respect to the critical density at $z=0.22$, implying a total mass of $\sim 4.6$--$16 \times 10^{17} M_\odot$, most of which in the form of low-mass galaxy groups or smaller substructures.Comment: 12 pages, 9 figures, Accepted for publication in MNRA

Screening for angiotensin I-converting enzyme (ACE) inhibitory activity of enzymatic hydrolysates obtained from Azorean macroalgae

As part of ongoing studies into the isolation of antihypertensive peptides, 12 common macroalgae species from Azores were investigated for their potential angiotensinconverting enzyme (ACE) inhibitory properties. After optimization of enzymatic hydrolysis conditions, the anti-ACE activity was determined by high performance liquid chromatography (HPLC). The species under study include four Rhodophyta (Gelidium microdon, Osmundea pinnatifida, Porphyra sp. and Pterocladiella capillacea), four Chlorophyta (Chaetomorpha linum, Codium adhaerens, Ulva compressa and Ulva rigida) and four Heterokontophyta (Cystoseira humilis, Fucus spiralis, Padina pavonica and Sargassum cymosum). The bromelain hydrolysates derived from P. capillacea, Porphyra sp., F. spiralis, U. compressa, O. pinnatifida and U. rigida were the most active presenting an ACE inhibitory activity of 48.73 ± 1.58%, 50.96 ± 1.82%, 56.77 ± 1.80%, 59.80 ± 0.95%, 62.59 ± 1.60% and 65.68 ± 0.72%, respectively. These results suggest that some macroalgae from the littoral Azorean sea are potential sources of powerful ACE inhibitor peptides, with potential impact on public health, particularly on the hypertensive patients. These features make these algae valuable to the regional economy and may also provide an incentive for marine biodiversity conservation and valuation of marine algal resources

Formation of a spiral galaxy in a major merger

We use numerical simulations to examine the structure of merger remnants resulting from collisions of gas-rich spiral galaxies. When the gas fraction of the progenitors is small, the remnants structurally and kinematically resemble elliptical galaxies, in agreement with earlier work. However, if the progenitor disks are gas-dominated, new types of outcomes are possible. In fact, we show that a prominent disk may survive in certain cases. To illustrate this scenario, we analyze an extreme example with progenitor galaxies consisting of dark matter halos, pure gas disks, and no bulges, as might be appropriate for mergers at high redshifts. While rapid star formation triggered by tidal torques during the merger forms a central, rotating bulge in the remnant, not all the gas is consumed in the burst. The remaining gas cools very quickly and settles into an extended star-forming disk, yielding an object similar to a spiral galaxy, and not an early type galaxy. This is contrary to the usual view that major mergers invariably destroy disks. The morphological evolution of galaxies can therefore be more complicated than often assumed, and in particular, theoretical constraints based on the fragility of spiral disks need to be reevaluated.Comment: submitted to ApJL, 4 figure

Ocorrência de reação sorológica contra Diarréia Viral Bovina e Rinotraqueíte Infecciosa Bovina em caprinos e bovinos de um rebanho com histórico de abortos em Sobral, Ceará.

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