A New Crocodylian from the Late Maastrichtian of Spain: Implications for the Initial Radiation of Crocodyloids

The earliest crocodylians are known primarily from the Late Cretaceous of North America and Europe. The representatives of Gavialoidea and Alligatoroidea are known in the Late Cretaceous of both continents, yet the biogeographic origins of Crocodyloidea are poorly understood. Up to now, only one representative of this clade has been known from the Late Cretaceous, the basal crocodyloid Prodiplocynodon from the Maastrichtian of North America.The fossil studied is a skull collected from sandstones in the lower part of the Tremp Formation, in Chron C30n, dated at -67.6 to 65.5 Ma (late Maastrichtian), in Arén (Huesca, Spain). It is located in a continuous section that contains the K/P boundary, in which the dinosaur faunas closest to the K/P boundary in Europe have been described, including Arenysaurus ardevoli and Blasisaurus canudoi. Phylogenetic analysis places the new taxon, Arenysuchus gascabadiolorum, at the base of Crocodyloidea.The new taxon is the oldest crocodyloid representative in Eurasia. Crocodyloidea had previously only been known from the Palaeogene onwards in this part of Laurasia. Phylogenetically, Arenysuchus gascabadiolorum is situated at the base of the first radiation of crocodyloids that occurred in the late Maastrichtian, shedding light on this part of the cladogram. The presence of basal crocodyloids at the end of the Cretaceous both in North America and Europe provides new evidence of the faunal exchange via the Thulean Land Bridge during the Maastrichtian

Of Asian Forests and European Fields: Eastern U.S. Plant Invasions in a Global Floristic Context

Background: Biogeographic patterns of species invasions hold important clues to solving the recalcitrant ‘who’, ‘where’, and ‘why ’ questions of invasion biology, but the few existing studies make no attempt to distinguish alien floras (all non-native occurrences) from invasive floras (rapidly spreading species of significant management concern), nor have invasion biologists asked whether particular habitats are consistently invaded by species from particular regions. Methodology/Principal Findings: Here I describe the native floristic provenances of the 2629 alien plant taxa of the Eastern Deciduous Forest of the Eastern U.S. (EUS), and contrast these to the subset of 449 taxa that EUS management agencies have labeled ‘invasive’. Although EUS alien plants come from all global floristic regions, nearly half (45%) have native ranges that include central and northern Europe or the Mediterranean (39%). In contrast, EUS invasive species are most likely to come from East Asia (29%), a pattern that is magnified when the invasive pool is restricted to species that are native to a single floristic region (25 % from East Asia, compared to only 11 % from northern/central Europe and 2 % from the Mediterranean). Moreover, East Asian invaders are mostly woody (56%, compared to just 23 % of the total alien flora) and are significantly more likely to invade intact forests and riparian areas than European species, which dominate managed or disturbed ecosystems. Conclusions/Significance: These patterns suggest that the often-invoked ‘imperialist dogma ’ view of global invasion

Practice change in chronic conditions care: an appraisal of theories

Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background Management of chronic conditions can be complex and burdensome for patients and complex and costly for health systems. Outcomes could be improved and costs reduced if proven clinical interventions were better implemented, but the complexity of chronic care services appears to make clinical change particularly challenging. Explicit use of theories may improve the success of clinical change in this area of care provision. Whilst theories to support implementation of practice change are apparent in the broad healthcare arena, the most applicable theories for the complexities of practice change in chronic care have not yet been identified. Methods We developed criteria to review the usefulness of change implementation theories for informing chronic care management and applied them to an existing list of theories used more widely in healthcare. Results Criteria related to the following characteristics of chronic care: breadth of the field; multi-disciplinarity; micro, meso and macro program levels; need for field-specific research on implementation requirements; and need for measurement. Six theories met the criteria to the greatest extent: the Consolidate Framework for Implementation Research; Normalization Process Theory and its extension General Theory of Implementation; two versions of the Promoting Action on Research Implementation in Health Services framework and Sticky Knowledge. None fully met all criteria. Involvement of several care provision organizations and groups, involvement of patients and carers, and policy level change are not well covered by most theories. However, adaptation may be possible to include multiple groups including patients and carers, and separate theories may be needed on policy change. Ways of qualitatively assessing theory constructs are available but quantitative measures are currently partial and under development for all theories. Conclusions Theoretical bases are available to structure clinical change research in chronic condition care. Theories will however need to be adapted and supplemented to account for the particular features of care in this field, particularly in relation to involvement of multiple organizations and groups, including patients, and in relation to policy influence. Quantitative measurement of theory constructs may present difficulties

The mammalian centrosome and its functional significance

Primarily known for its role as major microtubule organizing center, the centrosome is increasingly being recognized for its functional significance in key cell cycle regulating events. We are now at the beginning of understanding the centrosome’s functional complexities and its major impact on directing complex interactions and signal transduction cascades important for cell cycle regulation. The centrosome orchestrates entry into mitosis, anaphase onset, cytokinesis, G1/S transition, and monitors DNA damage. Recently, the centrosome has also been recognized as major docking station where regulatory complexes accumulate including kinases and phosphatases as well as numerous other cell cycle regulators that utilize the centrosome as platform to coordinate multiple cell cycle-specific functions. Vesicles that are translocated along microtubules to and away from centrosomes may also carry enzymes or substrates that use centrosomes as main docking station. The centrosome’s role in various diseases has been recognized and a wealth of data has been accumulated linking dysfunctional centrosomes to cancer, Alstrom syndrome, various neurological disorders, and others. Centrosome abnormalities and dysfunctions have been associated with several types of infertility. The present review highlights the centrosome’s significant roles in cell cycle events in somatic and reproductive cells and discusses centrosome abnormalities and implications in disease

Structural, Metabolic, and Functional Brain Abnormalities as a Result of Prenatal Exposure to Drugs of Abuse: Evidence from Neuroimaging

Prenatal exposure to alcohol and stimulants negatively affects the developing trajectory of the central nervous system in many ways. Recent advances in neuroimaging methods have allowed researchers to study the structural, metabolic, and functional abnormalities resulting from prenatal exposure to drugs of abuse in living human subjects. Here we review the neuroimaging literature of prenatal exposure to alcohol, cocaine, and methamphetamine. Neuroimaging studies of prenatal alcohol exposure have reported differences in the structure and metabolism of many brain systems, including in frontal, parietal, and temporal regions, in the cerebellum and basal ganglia, as well as in the white matter tracts that connect these brain regions. Functional imaging studies have identified significant differences in brain activation related to various cognitive domains as a result of prenatal alcohol exposure. The published literature of prenatal exposure to cocaine and methamphetamine is much smaller, but evidence is beginning to emerge suggesting that exposure to stimulant drugs in utero may be particularly toxic to dopamine-rich basal ganglia regions. Although the interpretation of such findings is somewhat limited by the problem of polysubstance abuse and by the difficulty of obtaining precise exposure histories in retrospective studies, such investigations provide important insights into the effects of drugs of abuse on the structure, function, and metabolism of the developing human brain. These insights may ultimately help clinicians develop better diagnostic tools and devise appropriate therapeutic interventions to improve the condition of children with prenatal exposure to drugs of abuse