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Using the weak gravitational lensing data from the Hyper Suprime-Cam Subaru Strategic Program (HSC survey), we study the potential of different stellar mass estimates in tracing halo mass. We consider galaxies with log10(M∗/M⊙) > 11.5 at 0.2 < z < 0.5 with carefully measured light profiles, and clusters from the redMaPPer and CAMIRA richness-based algorithms. We devise a method (the 'Top-N test') to evaluate the scatter in the halo mass-observable relation for different tracers, and to inter-compare halo mass proxies in four number density bins using stacked galaxy-galaxy lensing profiles. This test reveals three key findings. Stellar masses based on CModel photometry and aperture luminosity within R

Individuals who are privileged are often unaware of the unearned advantages that they have. Because of this lack of awareness, individuals with privilege may attribute poor performance of a non-privileged individual to that individual's lack of effort or ability, rather than recognizing that the non-privileged person may not have had sufficient opportunities or resources. Without fully being aware of such privilege, it can be difficult for students to appreciate the diversity surrounding them, both in the classroom and in the workplace. This experiential exercise and suggested debrief strategies illustrate the concept and consequences of privilege.

Translational ecology defines a collaborative effort among scientists and stakeholders to rapidly translate environmental problems into action. This approach can be applied in a fisheries management context when information needed to inform regulations is unavailable, yet conservation concerns exist. Our research uses a translational ecology framework to assess the stock status and develop research priorities for the crevalle jack (Caranx hippos) in the Florida Keys, USA, a currently unregulated species. Interview data that compiled expert fishing guide knowledge were used to develop hypotheses tested using existing fisheries-dependent datasets to check for agreement among sources and assess the consistency of observed patterns. Six hypotheses were developed concerning the status and trends of the crevalle jack population in the Florida Keys, and four of these hypotheses received clear support, with agreement between guide observations and one or more of the fisheries-dependent datasets. The results of our study outline an effective translational ecology approach for recreational fisheries management designed to rapidly recognize potential management needs as identified by fishing guides, which allows for actionable science and proactive management. L'ecologie traductionnelle designe les efforts de collaboration de chercheurs et de parties prenantes visant a traduire rapidement des problemes environnementaux en gestes concrets. Cette approche peut etre appliquee dans un contexte de gestion des peches quand l'information necessaire a l'elaboration de reglements n'est pas disponible, mais qu'il existe des situations preoccupantes. Nos travaux font appel a un cadre d'ecologie traductionnelle pour evaluer l'etat du stock et etablir des priorites de recherche pour une espece actuellement visee par aucune reglementation, la carangue crevalle (Caranx hippos), dans les Keys de la Floride (Etats-Unis). Des donnees d'interviews recensant les connaissances de guides de peche chevronnes sont utilisees pour formuler des hypotheses testees a l'aide d'ensembles existants de donnees dependantes de la peche pour verifier la concordance de differentes sources et evaluer la coherence des motifs observes. Six hypotheses sont formulees concernant l'etat et les tendances de la population de carangues crevalles dans les Keys de la Floride, et l'analyse appuie clairement quatre de ces hypotheses, pour lesquelles les observations des guides et un ou plusieurs des ensembles de donnees dependantes de la peche concordent. Les resultats de l'etude delimitent une approche efficace d'ecologie traductionnelle pour la gestion des peches sportives, conque pour faire rapidement ressortir les besoins potentiels de gestion cernes par les guides de peche et permettant du coup des applications pratiques de resultats scientifiques et une gestion proactive. [Traduit par la Redaction], Introduction In today's world of anthropogenic global change and urgent ecological crises, clear pathways for actionable science are more important than ever (Chapin 2017). Translational ecology (TE) is a developing [...]

Using the weak gravitational lensing data from the Hyper Suprime-Cam Subaru Strategic Program (HSC survey), we study the potential of different stellar mass estimates in tracing halo mass. We consider galaxies with log10(M ⋆/M⊙) > 11.5 at 0.2 < z < 0.5 with carefully measured light profiles, and clusters from the redMaPPer and CAMIRA richness-based algorithms. We devise a method (the 'Top- N test') to evaluate the scatter in the halo mass–observable relation for different tracers, and to inter-compare halo mass proxies in four number density bins using stacked galaxy–galaxy lensing profiles. This test reveals three key findings. Stellar masses based on CModel photometry and aperture luminosity within R <30 kpc are poor proxies of halo mass. In contrast, the stellar mass of the outer envelope is an excellent halo mass proxy. The stellar mass within R  = [50, 100] kpc, M ⋆, [50, 100], has performance comparable to the state-of-the-art richness-based cluster finders at log10 M vir ≳ 14.0 and could be a better halo mass tracer at lower halo masses. Finally, using N -body simulations, we find that the lensing profiles of massive haloes selected by M ⋆, [50, 100] are consistent with the expectation for a sample without projection or mis-centring effects. Richness-selected clusters, on the other hand, display an excess at R ∼ 1 Mpc in their lensing profiles, which may suggest a more significant impact from selection biases. These results suggest that M ⋆-based tracers have distinct advantages in identifying massive haloes, which could open up new avenues for cluster cosmology. The codes and data used in this work can be found here: [ABSTRACT FROM AUTHOR]

As part of the effort to meet the needs of the Large Synoptic Survey Telescope Dark Energy Science Collaboration (LSST DESC) for accurate, realistically complex mock galaxy catalogues, we have developed galsampler , an open-source python package that assists in generating large volumes of synthetic cosmological data. The key idea behind galsampler is to recast hydrodynamical simulations and semi-analytic models as physically motivated galaxy libraries. galsampler populates a new, larger volume halo catalogue with galaxies drawn from the baseline library; by using weighted sampling guided by empirical modelling techniques, galsampler inherits statistical accuracy from the empirical model and physically motivated complexity from the baseline library. We have recently used galsampler to produce the cosmoDC2 extragalactic catalogue made for the LSST DESC Data Challenge 2. Using cosmoDC2 as a guiding example, we outline how galsampler can continue to support ongoing and near-future galaxy surveys such as the Dark Energy Survey, the Dark Energy Spectroscopic Instrument, WFIRST , and Euclid. [ABSTRACT FROM AUTHOR]

Using deep images from the Hyper Suprime-Cam (HSC) survey and taking advantage of its unprecedented weak lensing capabilities, we reveal a remarkably tight connection between the stellar mass distribution of massive central galaxies and their host dark matter halo mass. Massive galaxies with more extended stellar mass distributions tend to live in more massive dark matter haloes. We explain this connection with a phenomenological model that assumes, (1) a tight relation between the halo mass and the total stellar content in the halo, (2) that the fraction of in situ and ex situ mass at r <10 kpc depends on halo mass. This model provides an excellent description of the stellar mass functions (SMFs) of total stellar mass (⁠|$M_{\star }^{\mathrm{max}}$|⁠) and stellar mass within inner 10 kpc (⁠|$M_{\star }^{10}$|⁠) and also reproduces the HSC weak lensing signals of massive galaxies with different stellar mass distributions. The best-fitting model shows that halo mass varies significantly at fixed total stellar mass (as much as 0.4 dex) with a clear dependence on |$M_{\star }^{10}$|⁠. Our two-parameter |$M_{\star }^{\mathrm{max}}$| – |$M_{\star }^{10}$| description provides a more accurate picture of the galaxy–halo connection at the high-mass end than the simple stellar–halo mass relation (SHMR) and opens a new window to connect the assembly history of haloes with those of central galaxies. The model also predicts that the ex situ component dominates the mass profiles of galaxies at r < 10 kpc for log  M ⋆ ≥ 11.7. The code used for this paper is available online https://github.com/dr-guangtou/asap [ABSTRACT FROM AUTHOR]

Obesity is primarily due to food intake in excess of the body's energetic requirements, intake that is not only associated with hunger but also the incentive value of food. The 5-hydroxytryptamine 2C receptor (5-HT 2C R) is a target for the treatment of human obesity. Mechanistically, 5-HT 2C Rs are positioned to influence both homeostatic feeding circuits within the hypothalamus and reward circuits within the ventral tegmental area (VTA). Here we investigated the role of 5-HT 2C Rs in incentive motivation using a mathematical model of progressive ratio (PR) responding in mice. We found that the 5-HT 2C R agonist lorcaserin significantly reduced both ad libitum chow intake and PR responding for chocolate pellets and increased c-fos expression in VTA 5-HT 2C R expressing γ-aminobutyric acid (GABA) neurons, but not 5-HT 2C R expressing dopamine (DA) neurons. We next adopted a chemogenetic approach using a 5-HT 2C R CRE line to clarify the function of subset of 5-HT 2C receptor expressing VTA neurons in the modulation of appetite and food-motivated behavior. Activation of VTA 5-HT 2C receptor expressing neurons significantly reduced ad libitum chow intake, operant responding for chocolate pellets, and the incentive value of food. In contrast, chemogenetic inhibition of VTA 5-HT 2C receptor expressing neurons had no effect on the feeding behavior. These results indicate that activation of the subpopulation of 5-HT 2C R neurons within the VTA is sufficient to significantly reduce homeostatic feeding and effort-based intake of palatable food, and that this subset has an inhibitory role in motivational processes. These findings are relevant to the treatment of obesity.