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Ceratopsians were herbivorous dinosaurs that dominated many of the terrestrial ecosystems in Asia and North America during the Cretaceous. The bizarre variety of skulls and lower jaw morphologies as well as the inferred ecological abundance of many species in this clade indicate that Ceratopsia was a successful group. Here we analyzed 126 lower jaws from 50 ceratopsian species, using two-dimensional geometric morphometrics and finite element analysis to investigate differences in shape and structural performance of this part of the feeding apparatus across Ceratopsia. Morphological differences in lower jaws across ceratopsian clades are said to originate from feeding adaptation. Our results show that the stress (physical loadings modeled in response to biting) in lower jaws was quite similar between “basal” and “derived” taxa, whereas major differences among clades occur for stress values associated with the coronoid process. The basal ceratopsians Hualianceratops and Yinlong had a highly stressed and primitive lower jaw, indicating that those animals may have fed on relatively soft foliage and fruits. A similar condition was found for basal neoceratopsians and protoceratopsids. Psittacosaurids possessed a well-integrated and compact lower jaw able to withstand high stress, at the cost of having a highly stressed coronoid process. Leptoceratopsids were characterized by the opposite condition. Taxa such as Leptoceratops , Prenoceratops , Zhuchengceratops and Cerasinops appear to have had a comparatively efficient feeding apparatus. Ceratopsidae represents the clade with the most efficient masticatory apparatus within Ceratopsia, even if the horizontal ramus of the lower jaw appears less able to withstand high levels of stress as compared with other ceratopsians. Additionally, we found the dentary and surangular–angular complex co-evolved to generate a masticatory apparatus able to withstand high stress, particularly in Protoceratopsidae and Triceratopsini. The major phenotypic evolutionary rate and morphological changes occurred during the mid- to Late Cretaceous, when intense climate change and angiosperm diversification could have affected the evolution of ecological diversity and feeding biomechanics in Ceratopsia. [ABSTRACT FROM AUTHOR]

Objectives To study coronary heart disease (CHD) incidence versus other cause of death using the cumulative incidence function and the competing risks procedures to disentangle the differential role of risk factors for different end-points. Material and methods We compared standard Cox and Fine-Gray models among 1677 middle aged men of an Italian population study of cardiovascular diseases that reached 50 years of follow-up with the quasi extinction of the population. The incidence of either fatal or non-fatal cases in 50 years was used as primary event, while deaths from any other cause, mutually exclusive from the primary events, were considered as secondary events. We considered 10 selected risk factors. Results The main result was that cholesterol was significantly and positively related to incidence of CHD contrasted with deaths from any other cause. On the other hand, when the primary events were deaths from any other cause and the competing events were CHD, cholesterol was inversely and age positively related. This outcome did not exclude the predictive role of other risk factors, such as age, cigarettes, arm circumference (protective), systolic blood pressure, vital capacity (protective), cholesterol, corneal arcus and diabetes, documented by the Cox model, that had common roles for both end-points. Conclusions Fine-Gray model, initially proposed to handle adequately cumulative incidence function may thus prevent overestimation of risks related to the Kaplan–Meier based methods such as Cox model and identify the specific risk factors for defined end-points. [ABSTRACT FROM AUTHOR]

Abstract: The application of a new method for the analysis of the large mammal Plio-Quaternary communities of mainland Italy is presented. This method, named “bootstrapped cluster analysis”, avoids, by mean of successive, ever more inclusive cluster analyses, the subjectivity in positioning boundaries of paleocommunities subdivisions. The results of this procedure indicate a good correspondence with previous qualitative analyses, albeit with some differences. Nevertheless, some local assemblages (e.g. Slivia) are grouped in significantly different positions than previously. The principal cause of these differences (as for unbalanced carnivores/herbivores ratio) is taphonomic bias. The bootstrapped cluster analysis approach is not affected by single species positioning as biochronological markers, grouping local assemblages upon their entire record with a statistical treatment. Moreover in this way any single paleocommunity is recognizable as an ecological/evolutionary unit. [Copyright &y& Elsevier]

In 1979, several specimens of Rhinocerotidae were collected from the Late Miocene deposits of the Zala Subbasin, Pannonian Basin, Western Hungary and were inventoried as Rhinoceros sp. Based on morphological and metric grounds, this material is here referred to “ Dihoplus ” megarhinus (de Christol), a species previously known only from Pliocene localities. This is the earliest record of the species in Europe. Our results support the hypothesis that the origin of “ D ”. megarhinus took place in Asia and that this species successively dispersed towards Western Europe during the end of the Miocene. [ABSTRACT FROM AUTHOR]