Laboratory millimeter and submillimeter spectrum of HOC^+

The J = 1→2, 2→3, and 3→4 rotational transitions of the molecular ion HOC^+ have been measured in the laboratory at frequencies from 178 to 358 GHz. The data should permit astronomers to confirm the recent possible sighting of the J = 1→0 transition of HOC^+ in Sgr B2 at 89.5 GHz

The millimeter and submillimeter laboratory spectrum of methyl formate in its ground symmetric torsional state

Over 200 rotational lines of methyl formate in its ground (v-t = 0), symmetric (A) torsional state have been measured in the frequency range 140-550 GHz. Analysis of these and lower frequency transitions permits accurate prediction (≤0.1 MHz) of over 10,000 transitions at frequencies below 600 GHz with angular momentum J ≤ 50. The measured spectral lines have permitted identification of over 100 new methyl formate lines in Orion

The laboratory millimeter-wave spectrum of methyl formate in its ground torsional E state

Over 250 rotational transitions of the internal rotor methyl formate (HCOOCH_3) in its ground v_t = 0 degenerate (E) torsional substate have been measured in the millimeter-wave spectral region. These data and a number of E-state lines identified by several other workers have been analyzed using an extension of the classical principal-axis method in the high barrier limit. The resulting rotational constants allow accurate prediction of the v_t = 0 E substate methyl formate spectrum below 300 GHz between states with angular momentum J ≤ 30 and rotational energy E_(rot)≤ 350cm^(-1). The calculated transition frequencies for the E state, when combined with the results of the previous analysis of the ground-symmetric, nondegenerate state, account for over 200 of the emission lines observed toward Orion in a recent survey of the 215-265 GHz band

Cardio-audio synchronization drives neural surprise response.

Successful prediction of future events depends on the brain's capacity to extract temporal regularities from sensory inputs. Neuroimaging studies mainly investigated regularity processing for exteroceptive sensory inputs (i.e. from outside the body). Here we investigated whether interoceptive signals (i.e. from inside the body) can mediate auditory regularity processing. Human participants passively listened to sound sequences presented in synchrony or asynchrony to their heartbeat while concomitant electroencephalography was recorded. We hypothesized that the cardio-audio synchronicity would induce a brain expectation of future sounds. Electrical neuroimaging analysis revealed a surprise response at 158-270 ms upon omission of the expected sounds in the synchronous condition only. Control analyses ruled out that this effect was trivially based on expectation from the auditory temporal structure or on differences in heartbeat physiological signals. Implicit neural monitoring of temporal regularities across interoceptive and exteroceptive signals drives prediction of future events in auditory sequences

Numerical simulations challenged on the prediction of massive subhalo abundance in galaxy clusters: the case of Abell 2142

In this Letter we compare the abundance of member galaxies of a rich, nearby ($z=0.09$) galaxy cluster, Abell 2142, with that of halos of comparable virial mass extracted from sets of state-of-the-art numerical simulations, both collisionless at different resolutions and with the inclusion of baryonic physics in the form of cooling, star formation, and feedback by active galactic nuclei. We also use two semi-analytical models to account for the presence of orphan galaxies. The photometric and spectroscopic information, taken from the Sloan Digital Sky Survey Data Release 12 (SDSS DR12) database, allows us to estimate the stellar velocity dispersion of member galaxies of Abell 2142. This quantity is used as proxy for the total mass of secure cluster members and is properly compared with that of subhalos in simulations. We find that simulated halos have a statistically significant ($\gtrsim 7$ sigma confidence level) smaller amount of massive (circular velocity above $200\,{\rm km\, s^{-1}}$) subhalos, even before accounting for the possible incompleteness of observations. These results corroborate the findings from a recent strong lensing study of the Hubble Frontier Fields galaxy cluster MACS J0416 \citep{grillo2015} and suggest that the observed difference is already present at the level of dark matter (DM) subhalos and is not solved by introducing baryonic physics. A deeper understanding of this discrepancy between observations and simulations will provide valuable insights into the impact of the physical properties of DM particles and the effect of baryons on the formation and evolution of cosmological structures.Comment: 8 pages, 2 figures. Modified to match the version published in ApJ

Stellar Ages and Metallicities of Central and Satellite Galaxies: Implications for Galaxy Formation and Evolution

Using a large SDSS galaxy group catalogue, we study how the stellar ages and metallicities of central and satellite galaxies depend on stellar mass and halo mass. We find that satellites are older and metal-richer than centrals of the same stellar mass. In addition, the slopes of the age-stellar mass and metallicity-stellar mass relations are found to become shallower in denser environments. This is due to the fact that the average age and metallicity of low mass satellite galaxies increase with the mass of the halo in which they reside. A comparison with the semi-analytical model of Wang et al. (2008) shows that it succesfully reproduces the fact that satellites are older than centrals of the same stellar mass and that the age difference increases with the halo mass of the satellite. This is a consequence of strangulation, which leaves the stellar populations of satellites to evolve passively, while the prolonged star formation activity of centrals keeps their average ages younger. The resulting age offset is larger in more massive environments because their satellites were accreted earlier. The model fails, however, in reproducing the halo mass dependence of the metallicities of low mass satellites, yields metallicity-stellar mass and age-stellar mass relations that are too shallow, and predicts that satellite galaxies have the same metallicities as centrals of the same stellar mass, in disagreement with the data. We argue that these discrepancies are likely to indicate the need to (i) modify the recipes of both supernova feedback and AGN feedback, (ii) use a more realistic description of strangulation, and (iii) include a proper treatment of the tidal stripping, heating and destruction of satellite galaxies. [Abridged]Comment: 20 pages, 12 figures, submitted for publication in MNRA

Impacto das Piores Experiências Escolares em Estudantes: Um Estudo Retrospectivo Sobre Trauma

AbstractThe literature indicates damage to students' mental health in cases of school violence. The aim of this retrospective study was to evaluate the psychological impact of school victimization in university students, and to analyze the association between PTSD symptoms and variables related to school victimization. 691 University students responded to the Portuguese version of the Student Alienation and Trauma Survey (SATS). Clinically significant scores in the subscales ranged from 4.7% (somatic symptoms) to 20% (hypervigilance), with frequent symptoms described in the literature resulting from school victimization, such as depression, hopelessness, cognitive difficulties, and traumatic event recollection. Additionally, 7.8% of participants presented PTSD symptoms after suffering their "worst school experience". Associations were found between PTSD symptoms and the level of distress after the experience, as well as the perceived benefits after the event, and duration. The results confirm the potential detrimental effects of school victimization, and may be useful to further investigations on this topic.ResumenLa literatura indica que casos de violencia en el contexto escolar causan daños a la salud mental de los estudiantes. El objetivo de este estudio retrospectivo fue evaluar el impacto psicológico de la victimización escolar en estudiantes universitarios y analizar la asociación de los síntomas de TEPT con variables relacionadas a la victimización. Un total de 691 estudiantes universitarios respondieron a la Escala de Experiencias Traumáticas en los Estudiantes. Puntuaciones clínicamente significativas en las subescalas oscilaron entre el 4,7% (síntomas somáticos) y el 20% (hipervigilancia), y se encontraran síntomas frecuentes descritos en la literatura resultante de victimización, tales como: depresión, desesperanza, problemas cognitivos y recuerda excesiva del evento traumático. Además, el 7,8% tenía síntomas de TEPT un mes después de su peor experiencia escolar. Se encontraran asociaciones con los síntomas de TEPT y el malestar que se siente después de la experiencia; beneficios percibidos después del evento y su duración. Los resultados indican el potencial nocivo de las experiencias de victimización escolar y pueden contribuir a investigaciones futuras.ResumoA literatura indica a existência de danos para a saúde mental de estudantes em casos de violência no contexto escolar. O objetivo deste estudo retrospectivo foi avaliar o impacto psicológico da vitimização escolar em estudantes universitários e analisar a associação dos sintomas de TEPT com variáveis relacionadas à vitimização. No total, 691 estudantes universitários responderam à Escala sobre Experiências Traumáticas em Estudantes. Escores clinicamente significativos nas subescalas variaram de 4,7% (sintomas somáticos) a 20% (hipervigilância), sendo frequentes sintomas descritos na literatura resultantes de vitimização, como: depressão, desesperança, dificuldades cognitivas e rememoração do evento traumático. Adicionalmente, 7,8% apresentaram sintomas de TEPT após a sua pior experiência escolar. Foram encontradas associações entre os sintomas de TEPT e o incômodo sentido após a experiência, benefícios percebidos após o evento e duração do mesmo. Tais dados indicam o potencial nocivo das experiências de vitimização escolar, podendo contribuir para futuras pesquisas em tal área

Fossil Groups in the Millennium Simulation. Evolution of the Brightest Galaxies

We create a catalogue of simulated fossil groups and study their properties, in particular the merging histories of their first-ranked galaxies. We compare the simulated fossil group properties with those of both simulated non-fossil and observed fossil groups. Using simulations and a mock galaxy catalogue, we searched for massive ($>$ 5 $\times$ 10$^{13} h^{-1} {\cal M}_\odot$) fossil groups in the Millennium Simulation Galaxy Catalogue. In addition, attempted to identify observed fossil groups in the Sloan Digital Sky Survey Data Release 6 using identical selection criteria. Our predictions on the basis of the simulation data are:(a) fossil groups comprise about 5.5% of the total population of groups/clusters with masses larger than 5 x 10$^{13} h^{-1} {\cal M}_\odot$. This fraction is consistent with the fraction of fossil groups identified in the SDSS, after all observational biases have been taken into account; (b) about 88% of the dominant central objects in fossil groups are elliptical galaxies that have a median R-band absolute magnitude of $\sim -23.5-5 log h$, which is typical of the observed fossil groups known in the literature; (c)first-ranked galaxies of systems with ${\cal M} >$ 5 x 10$^{13} h^{-1} {\cal M}_\odot$, regardless of whether they are either fossil or non-fossil, are mainly formed by gas-poor mergers; (d) although fossil groups, in general, assembled most of their virial masses at higher redshifts in comparison with non-fossil groups, first-ranked galaxies in fossil groups merged later, i.e. at lower redshifts, compared with their non-fossil-group counterparts. We therefore expect to observe a number of luminous galaxies in the centres of fossil groups that show signs of a recent major merger.Comment: 9 pages, 3 figures, accepted for publication in Astronomy & Astrophysic