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Frogs are an ecologically diverse and phylogenetically ancient group of anuran amphibians that include important vertebrate cell and developmental model systems, notably the genus Xenopus. Here we report a high-quality reference genome sequence for the western clawed frog, Xenopus tropicalis, along with draft chromosome-scale sequences of three distantly related emerging model frog species, Eleutherodactylus coqui, Engystomops pustulosus, and Hymenochirus boettgeri. Frog chromosomes have remained remarkably stable since the Mesozoic Era, with limited Robertsonian (i.e., arm-preserving) translocations and end-to-end fusions found among the smaller chromosomes. Conservation of synteny includes conservation of centromere locations, marked by centromeric tandem repeats associated with Cenp-a binding surrounded by pericentromeric LINE/L1 elements. This work explores the structure of chromosomes across frogs, using a dense meiotic linkage map for X. tropicalis and chromatin conformation capture (Hi-C) data for all species. Abundant satellite repeats occupy the unusually long (~20 megabase) terminal regions of each chromosome that coincide with high rates of recombination. Both embryonic and differentiated cells show reproducible associations of centromeric chromatin and of telomeres, reflecting a Rabl-like configuration. Our comparative analyses reveal 13 conserved ancestral anuran chromosomes from which contemporary frog genomes were constructed.

Chronic kidney disease is an important clinical condition beset with racial and ethnic disparities that are associated with social inequities. Many medical schools and health centres across the USA have raised concerns about the use of race - a socio-political construct that mediates the effect of structural racism - as a fixed, measurable biological variable in the assessment of kidney disease. We discuss the role of race and racism in medicine and outline many of the concerns that have been raised by the medical and social justice communities regarding the use of race in estimated glomerular filtration rate equations, including its relationship with structural racism and racial inequities. Although race can be used to identify populations who experience racism and subsequent differential treatment, ignoring the biological and social heterogeneity within any racial group and inferring innate individual-level attributes is methodologically flawed. Therefore, although more accurate measures for estimating kidney function are under investigation, we support the use of biomarkers for determining estimated glomerular filtration rate without adjustments for race. Clinicians have a duty to recognize and elucidate the nuances of racism and its effects on health and disease. Otherwise, we risk perpetuating historical racist concepts in medicine that exacerbate health inequities and impact marginalized patient populations.

Systems thinking is recognized as an essential skill for understanding complex problem solving and decision making associated with many of the contemporary issues faced by individuals and communities. In this article, our goal is to contribute to the knowledge of curriculum and pedagogy of formal systems thinking teaching in higher education. We believe that accumulating this knowledge can provide a better foundation for including systems thinking in higher-educational programs. To achieve this goal, the purpose of this study is to examine whether the use of a set of systems thinking concepts and methods can effectively promote systems thinking in higher-education settings. The study shows that systems thinking skills can be promoted effectively through the delivery of a combination of systems thinking methods and concepts.

A monodominant Gryposaurus sp. bonebed in the lower unit of the Campanian Oldman Formation of southern Alberta is the oldest hadrosauroid bonebed documented in the province and the first described from the formation. The sedimentology of the locality and the taphonomy of the hadrosaurid material indicates that the bonebed represents an assemblage of juvenile-sized individuals that were probably transported only a short distance from where they died to where they were finally deposited and preserved in a fine-grained mudstone within an overbank sequence. Histological examination of six limb elements confirms that all individuals are juveniles, with two age classes ( Key words: Gryposaurus, hadrosauridae, Belly River Group, Oldman Formation, Campanian, taphonomy. Un lit a ossements monodominants de Gryposaurus sp., dans l'unite inferieure de la Formation campanienne d'Oldman du sud de l'Alberta, constitue le plus ancien lit a ossements d'hadrosauroides documente dans la province et le premier decrit de cette formation. La sedimentologie de la localite et la taphonomie du materiau d'hadrosaurides indiquent que le lit represente un assemblage d'individus de taille juvenile qui n'ont probablement ete transportes que sur une courte distance depuis le lieu de leur mort jusqu'au lieu de leur depot final et de leur preservation dans un mudstone fin au sein d'une sequence de debordement. L'examen histologique de six elements des membres confirme que tous les individus sont des juveniles de deux classes d'ages ( Mots-cles: Gryposaurus, hadrosaurides, Groupe de Belly River, Formation d'Oldman, Campanien, taphonomie., Introduction Hadrosauridae is a diverse family of large-bodied ornithischian herbivores that flourished during the Late Cretaceous (Horner et al. 2004; Prieto-Marquez 2010) as large-bodied terrestrial herbivores of the Late Cretaceous [...]

The pre-Campanian trionychid fossil record in North America is composed of highly fragmentary specimens, which are often not identifiable beyond Pan-Trionychidae. Here, we describe a new species of plastomenid soft-shelled turtle based on a partial shell (ROM 56647) from the Santonian Milk River Formation of southern Alberta, estimated at approximately 84 Ma. This represents the oldest relatively complete shell of a trionychid from North America. Plastomenidae, a pan-trionychid clade known only from the fossil record, is classically characterized by the complete suturing of its posterior plastral bones along the midline, a crescent-shaped entoplastron, and enlarged costals VIII. ROM 56647 has a unique combination of plastomenid characters (i.e., mid-line contact of hypoplastra and xiphiplastra, anteroposteriorly long eighth costal) and apomorphies (an emarginate nuchal, enlarged tubercles on the carapace, a wide pygal notch with a straight anterior edge, and a fused hyo-hypoplastron) that allows us to identify it as a new taxon, Jimemys glaebosus gen. et sp. nov. Phylogenetic analysis places J. glaebosus within Plastomenidae as the sister taxon to a clade containing Plastomenus, Helopanoplia, and Hutchemys. This phylogenetic position implies that Aspideretoides foveatus Leidy, 1856, Atoposemys, and Gilmoremys, all of which are more basal within Plastomenidae, had ghost lineages extending at least to the Santonian. As the oldest pan-trionychid that is diagnostic to the species level in North America, J. glaebosus provides new insights into both the early evolution of trionychids in North America and the biodiversity of southern Alberta during a poorly sampled time in the Late Cretaceous of North America. Key words: Testudines, Trionychidae, Plastomenidae, soft-shelled turtle, Santonian, Late Cretaceous, North America. Le registre fossile des trionychides pre-campaniens en Amerique du Nord est compose de specimens tres fragmentaires qu'il est souvent impossible d'identifier au-dela des pan-trionychides. Nous decrivons une nouvelle espece de tortue plastomenide a carapace molle a la lumiere d'une carapace partielle (ROM 56647) provenant de la Formation santonienne de Milk River du sud de l'Alberta, d'un age estime d'environ 84 Ma, ce qui represente la carapace relativement complete la plus ancienne d'un trionychide d'Amerique du Nord. Le clade pan-trionychide des plastomenides, reconnu seulement dans le registre fossile, est traditionnellement caracterise par la suture complete de ses os plastraux posterieurs le long de la mediane, un entoplastron en forme de croissant et des os costaux VIII de grandes dimensions. ROM 56647 presente une combinaison singuliere de caracteres de plastomenides (c.-a-d., contact le long de la mediane d'hypoplastrons et de xiphiplastrons, longue dimension anteroposterieure du huitieme costal) et d'apomorphies (nucal emargine, grands tubercules sur la carapace, large echancrure pygale presentant une bordure anterieure rectilineaire et hyo-hypoplastron fusionne) qui nous permet de l'identifier comme etant un nouveau taxon, Jimemys glaebosus gen. et sp. nov. L'analyse phylogenetique positionne J. glaebosus au sein des plastomenides, en tant que taxon frere d'un clade comptant Plastomenus, Helopanoplia et Hutchemys. Cette position phylogenetique sous-entend que Aspideretoides foveatus Leidy, 1856, Atoposemys et Gilmoremys, qui occupent tous des positions plus basales au sein des plastomenides, ont eu des lignees fantomes se prolongeant au moins jusqu'au Santonien. A titre de plus ancien pan-trionychide pouvant etre diagnostique jusqu'au niveau de l'espece en Amerique du Nord, J. glaebosus fournit des renseignements utiles sur l'evolution precoce des trionychides en Amerique du Nord, ainsi que sur la biodiversite du sud de l'Alberta durant une periode peu echantillonnee du Cretace tardif d'Amerique du Nord. Mots-cles : cheloniens, trionychides, plastomenides, tortue a carapace molle, Santonien, Cretace tardif, Amerique du Nord., Introduction Pan-Trionychidae is a distinctive clade of turtles characterized by a highly reduced plastron, the loss of keratinous scales and peripheral bones, the presence of sculpturing on the carapace and [...]

Half of adults in the United States have hypertension as defined by clinical practice guidelines. Interestingly, women are generally more likely to be aware of their hypertension and have their blood pressure controlled with treatment compared with men, yet hypertension-related mortality is greater in women. This may reflect the fact that the female sex remains underrepresented in clinical and basic science studies investigating the effectiveness of therapies and the mechanisms controlling blood pressure. This Review provides an overview of the impact of the way hypertension research has explored sex as a biological variable (SABV). Emphasis is placed on epidemiological studies, hypertension clinical trials, the genetics of hypertension, sex differences in immunology and gut microbiota in hypertension, and the effect of sex on the central control of blood pressure. The goal is to offer historical perspective on SABV in hypertension, highlight recent studies that include SABV, and identify key gaps in SABV inclusion and questions that remain in the field. Through continued awareness campaigns and engagement/education at the level of funding agencies, individual investigators, and in the editorial peer review system, investigation of SABV in the field of hypertension research will ultimately lead to improved clinical outcomes. [ABSTRACT FROM AUTHOR]

Hadrosaurids are a diverse and widely distributed group of ornithischian dinosaurs that are particularly well represented in the upper Campanian Dinosaur Park Formation of the Belly River Group of Alberta. However, the origin of this hadrosaurid diversity in Alberta is poorly understood, as the lower Campanian terrestrial deposits of the underlying Oldman and Foremost formations of the group have produced comparatively few body fossils. Here we provide the first description of a partially articulated hadrosaurid and hadrosaurid material from a bonebed from the Foremost Formation and refer it to the brachylophosaurin Probrachylophosaurus sp. indet. The material represents the oldest occurrence of Brachylophosaurini in Alberta and the oldest known hadrosaurid diagnostic to the genus level from Canada. In Alberta, Hadrosaurinae display a distinct pattern of replacement with the tribes Brachylophosaurini and Kritosaurini being confined to the lower to middle Campanian strata (below the marine Bearpaw Formation) and replaced above the Bearpaw Formation by members of Saurolophini (Prosaurolophus, Saurolophus) and Edmontosaurini (Edmontosaurus), with the latter clade persisting to the end of the Maastrichtian. Although the worldwide stratigraphic distribution of the Hadrosaurinae is complex, this pattern generally holds true for northern Laramidian hadrosaurine tribes, suggesting that their pattern of evolution and replacement may be driven by some common underlying factor such as an environmental response to fluctuations in the margins of the Western Interior Seaway due to sea level change. Key words: Belly River Group, Foremost Formation, Hadrosauridae, Ornithischia, Cretaceous, Probrachylophosaurus. Les hadrosaurides constituent un groupe de dinosaures ornithischiens varie a la vaste repartition, particulierement bien representes dans la Formation de Dinosaur Park du Campanien superieur du Groupe de Belly River de l'Alberta. L'origine de cette diversite des hadrosaurides en Alberta demeure toutefois mal comprise, etant donne le peu de fossiles de corps produits par les depots terrestres campaniens inferieurs des Formations sous-jacentes d'Oldman et de Foremost du groupe. Nous presentons la premiere description d'un hadrosauride partiellement articule et de materiau d'hadrosauride provenant d'un lit a ossements de la Formation de Foremost et le renvoyons au brachylophosaurine Probrachylophosaurus sp. indet. Le materiau represente la presence la plus ancienne de brachylophosaurines en Alberta et le diagnostic d'hadrosauride connu au niveau du genre le plus ancien au Canada. En Alberta, les hadrosaurines presentent un motif distinctif de remplacement, les tribus des brachylophosaurines et des kritosaurines etant confinees aux strates du Campanien inferieur et moyen (sous la Formation marine de Bearpaw) et remplacees au-dessus de la Formation de Bearpaw par des membres des saurolophines (Prosaurolophus, Saurolophus) et des edmontosaurines (Edmontosaurus), ce dernier clade persistant jusqu'a la fin du Maastrichtien. Si la repartition stratigraphique mondiale des hadrosaurines est complexe, ce motif s'avere generalement pour les tribus d'hadrosaurines du nord de la Laramidie, ce qui indiquerait que leur motif d'evolution et de replacement pourrait etre module par un facteur sous-jacent commun tel que la reaction a des fluctuations des conditions ambiantes aux marges de la mer interieure de l'Ouest dues a des variations du niveau de la mer. [Traduit par la Redaction] Mots-cles : Groupe de Belly River, Formation de Foremost, hadrosaurides, ornithischiens, Cretace, Probrachylophosaurus., Introduction Hadrosauroidea was a globally distributed, diverse group of ornithopod dinosaurs that existed during the Late Cretaceous (Horner et al. 2004; Gates and Sampson 2007; Prieto-Marquez 2010b; Godefroit et al. [...]

We describe a new partial skull with braincase of a maiasaurin hadrosaurid from the Milk River Ridge Reservoir near Warner, southern Alberta, as the first diagnostic occurrence of Maiasaura in Canada. This material was collected in the Oldman Formation, at approximately the same stratigraphic level as a nearby bonebed of the ceratopsid Coronosaurus brinkmani. The assignment of this specimen to Maiasaura, rather than to Brachylophosaurus, is supported by the narrow and acute posterior margin of the external naris, the relationship between the postorbital and squamosal in the supratemporal bar, and the morphology of the frontals, which are greatly thickened and elevated anteriorly, with the dorsal surface not completely covered by the nasofrontal contact at adult size. The occurrence of both Maiasaura and Brachylophosaurus in approximately similar-aged deposits of the Comrey Sandstone zone in southern Alberta provides support for some cladogenesis in the evolutionary history of Maiasaurini. Geographically, the more western distribution of Maiasaura localities with respect to all Brachylophosaurus localities is consistent with the hypothesis that a preference for more inland versus seaway-adjacent habitats may have influenced the phylogenetic divergence of these taxa. Key words: Hadrosauridae, braincase, Oldman Formation, Campanian, Cretaceous, Dinosauria. Nous decrivons un nouveau crane partiel avec neurocrane d'un hadrosauride maiasaurine du reservoir de Milk River Ridge, pres de Warner (sud de l'Alberta), comme etant le premier cas signale diagnostique de Maiasaura au Canada. Ce materiau a ete preleve de la Formation d'Oldman, approximativement au meme niveau stratigraphique qu'un lit a ossements du ceratopside Coronosaurus brinkmani situe a proximite. L'affectation de ce specimen a Maiasaura, plutot qu'a Brachylophosaurus, est appuyee par la marge posterieure etroite et aigue du naris externe, la relation entre l'os postorbital et l'os squamosal dans la barre supratemporale et la morphologie des os frontaux, qui sont considerablement epaissis et eleves anterieurement, leur surface dorsale n'etant pas completement recouverte par le contact nasofrontal dans les exemples de taille adulte. La presence de Maiasaura et Brachylophosaurus dans des gisements d'age approximativement similaire de la zone du gres de Comrey dans le sud de l'Alberta appuie l'interpretation d'une certaine cladogenese dans l'histoire de l'evolution des Maiasaurines. Sur le plan geographique, la repartition plus occidentale des localites a Maiasaura par rapport a toutes les localites a Brachylophosaurus concorde avec l'hypothese selon laquelle des preferences d'habitats soit plus interieurs ou a cote de voies maritimes pourraient avoir influence la divergence phylogenetique de ces taxons. [Traduit par la Redaction] Mots-cles : hadrosaurides, neurocrane, Formation d'Oldman, Campanien, Cretace, dinosaures., Introduction Maiasaurini (originally Maiasaurinae, Horner 1992; =Brachylophosaurini, Gates et al. 2011) are recognized as the earliest-diverging clade of hadrosaurines present in Laramidia, and include both solid-crested and non-crested species (Gates [...]