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We present an empirical method of assessing the star formation rate (SFR) of star-forming galaxies based on their locations in the rest-frame color-color diagram (NUV - r) vs. (r - K). By using the Spitzer 24 μm sample in the COSMOS field (~16 400 galaxies with 0:2 ⩽ z ⩽ 1:3) and a local GALEX-SDSS-SWIRE sample (~700 galaxies with z ⩽ 0:2), we show that the mean infrared excess hIRXi = hLIR=LUVi can be described by a single vector, NRK, that combines the two colors. The calibration between hIRXi and NRK allows us to recover the IR luminosity, LIR, with an accuracy of σ ~ 0:21 for the COSMOS sample and 0.27 dex for the local one. The SFRs derived with this method agree with the ones based on the observed (UV+IR) luminosities and on the spectral energy distribution (SED) fitting for the vast majority (~85%) of the star-forming population. Thanks to a library of model galaxy SEDs with realistic prescriptions for the star formation history, we show that we need to include a two-component dust model (i.e., birth clouds and di use ISM) and a full distribution of galaxy inclinations in order to reproduce the behavior of the hIRXi stripes in the NUVrK diagram. In conclusion, the NRK method, based only on the rest-frame UV/optical colors available in most of the extragalactic fields, o ers a simple alternative of assessing the SFR of star-forming galaxies in the absence of far-IR or spectral diagnostic observations. [ABSTRACT FROM AUTHOR]

We show that the accumulated light of galaxies in the ultraviolet can be evaluated from their luminosity density as a function of the evolution of the cosmic star formation rate and dust extinction properties. Constraints on the evolution rate are expected in future. Data available at the moment are consistent with an evolution rate at low z steeper than (1 + z)3.5. A shallower rate remains possible if the luminosity-weighted dust extinction at 2000 Å, as suggested by some data, is lower than ∼1.2. [ABSTRACT FROM AUTHOR]

Police officer suicide rates hit an all-time high in the province of Ontario, Canada, in 2018. Sadly, this statistic is somewhat unsurprising, as research has shown that police officers suffer from higher rates of mental health disorder diagnoses compared to the general public. One key reason for the elevated levels of suicide and other mental health issues among police officers is believed to stem from the stigma associated with seeking help. In an attempt to address these serious issues, Ontario's police services have begun to create internal peer support programs as a way of supporting their members. The present research explores the experiences of police officers serving as peer-support team members, particularly with regards to the impacts of peer support. In addition, this research also examines the importance of discussing shared experiences regarding a lack of standardized procedures for the administration and implementation of peer support in relation to the Policy Feedback Theory. The Policy Feedback Theory (PFT) posits that, when a policy becomes established and resources are devoted to programs, it helps structure current activity. This study utilized a phenomenological, qualitative approach, with data collection consisting of face-to-face interviews with nine police officers serving on the York Regional Police's peer-support team. The findings revealed that peer support is more than just a "conversation"; rather, it suggests to contribute to enhancing mental health literacy among police officers, and it significantly contributes to stigma reduction. The findings also revealed that internal policy demonstrated an organizational commitment to mental health and peer-support, and that a provincial standard is necessary to ensure best practices and risk management in the creation and maintenance of peer-support programs., (Copyright © 2020 Milliard.)

Exposure to critical incidents and hence potentially traumatic events is endemic in law enforcement. The study of law enforcement officers' experience of moral injury and their exposure to potentially morally injurious incidents, and research on moral injury's relationship with different forms of traumatization (e.g. compassion fatigue, post-traumatic stress disorder) are in their infancy. The present study aims to build on prior research and explores the role of moral injury in predicting post-traumatic stress disorder (PTSD) and its clusters thereof. To this end, a sample of law enforcement officers ( N = 370) from the National Police of Finland was recruited to participate in the current study. Results showed that moral injury significantly predicted PTSD as well as its diagnostic clusters (i.e., avoidance, hyperarousal, re-experiencing). The aforementioned role of moral injury to significantly predict PTSD and its clusters were unequivocal even when compassion fatigue was incorporated into the path model. Clinical, research, and law enforcement practice implications are discussed., (Copyright © 2020 Papazoglou, Blumberg, Chiongbian, Tuttle, Kamkar, Chopko, Milliard, Aukhojee and Koskelainen.)

Detailed high-resolution observations of the innermost regions of nearby galaxies have revealed the presence of supermassive black holes. These black holes may interact with their host galaxies by means of 'feedback' in the form of energy and material jets; this feedback affects the evolution of the host and gives rise to observed relations between the black hole and the host. Here we report observations of the ultraviolet emissions of massive early-type galaxies. We derive an empirical relation for a critical black-hole mass (as a function of velocity dispersion) above which the outflows from these black holes suppress star formation in their hosts by heating and expelling all available cold gas. Supermassive black holes are negligible in mass compared to their hosts but nevertheless seem to play a critical role in the star formation history of galaxies.

We consider the problem of determining the unknown translation between two images. We analyze the performance of the optimal technique in presence of Poisson noise in comparison with the classical linear intercorrelation method, and we apply this approach to astronomical images.