467 research outputs found
Functional aspects of titanosaur osteoderms
Though titanosaur osteoderms are not common findings, these elements are recorded widely in Gondwana and part of Laurasia. This assembly known by the date offers few resources for studies on the ecology of this group of dinosaurs. Recently, some eggs bearing titanosaur embryos with preserved skin, from Patagonia, Argentina, may shed some light on the function and disposition pattern of these dermic bones. Some of the skin patches associated with the titanosaur embryos show two distinct patterns of tuberosities: a longitudinal row and rosettes, both composed of closely attached tuberosities. These tuberosities do not seem to be ossified, but this might be due to the ontogenetic stage of the titanosaurs. Here we propose that these tuberosities might have been ossified in later ontogenetic stages, and then turning into real osteoderms providing physical defence for the juvenile titanosaurs. Amongst the remains of large titanosaurs like _Mendozasaurus neguyelap_ some osteoderms were recovered, but it is contrasting small to the animal when compared to other dinosaurs. These bones would not provide real defensive advantage to an adult titanosaur as they are small and also have a very spongy internal structure. This apparent fragility also may be the reason that few titanosaur osteoderms have been preserved. In comparison, the tuberosity of a young titanosaur is much larger than an adult osteoderm and its body armor would be much more effective against small predators like notosuchian crocodyliforms and small theropods. And if the titanosaur osteoderms are originated from the embryo’s tuberosities, the disposition of these elements in an adult animal would be very distant to each other. The calcium reserve may be considered as functional for an adult titanosaur though
The locomotion pattern of Baurusuchus salgadoensis Carvalho, Nobre & Campos, 2005 and the distribution of Baurusuchidae in Gondwanaland
Baurusuchus salgadoensis Carvalho, Nobre & Campos, 2005 is a ziphodont mesoeucrocodylian closely related to the Sebecosuchia. Cranial features indicate that this species had terrestrial predatory habits. The postcranial skeleton of B. salgadoensis show distinctive characteristics when compared to extant Crocodylomorpha. The dorsal vertebrae are close articulated with short and craniocaudally expanded neural spines, specially the posterior ones. The sacral vertebrae are robust and have the lateral processes highly fused to the ilium. The anterior caudal vertebrae are robust as the sacral ones but their neural spines are more stout, anteriorlly expanded and higher. The close articulation of the dorsal vertebrae may indicate a less flexible dorsal spine, ideal to limb-driven methods of locomotion. The high and expanded neural spines of the posterior dorsal and sacral vertebrae are associated to muscle attachment from the osteoderms and the pelvic musculature, all used in the limb-driven locomotion. The appendicular bones of B. salgadoensis are long and stout. They show a straight aspect of their diaphysis and very well- developed epiphysis. The femur is long when compared to extant crocodilians, showing a straight aspect in lateral view and a slight sigmoid aspect in frontal view. There is a small axial torsion at its proximal end. The fourth trochanter is pronouced and posteriorlly oriented. The proximal end possess a mesial projection that articulates itself to the illium, similar to those of Protosuchia and thecodont archosaurs as the Rauisuchia. The illium of B. salgadoensis present a lateral and posteriorlly expanded postaccetabular crest, similar to those observed in Rauisuchia and Protosuchia, referred as overhanging ilium. This pattern of articulation is observed in the rauisuchian thecodonts and interpreted as a characteristic trait of those able erect-posture and limb-driven predators of Triassic environments. B. salgadoensis exoskeleton has only two dorsal osteoderm rows that run from the neck to the tip of the tail. Most of the osteoderms are wider than longer, with a round lateral portion that does not articulate to any flank osteoderm. The only morphological difference appears at the caudalmost portion of the tail, where the osteoderms are craniocaudally elongated. The medial portion has little variation along the scutes rows and may bear medial lamellar dorsoventral structures of articulation to the adjacent bony plate. The anterior articular facet is discreet and the osteoderms are not as imbricated as occur in other crocodyliforms and even may not be imbricated at all. The pelvic region osteoderms have the tallest keel of the row that runs from the anterior articular facet to posteriosmost portion of the osteoderm. B. salgadoensis has a light exoskeleton and then is less encumbranced by it. Therefore, becaming more agile. The imbrication of dorsal armor assists the limb-driven locomotion of many crocodyliform by reducing the flexibility of the dorsal spine during the high-walk (erect stance). Therefore the long and stout limb bones, overhanging crest of the illium and the light weighted armor, also allowed to B. salgadoensis to have the limb-driven locomotion without this pattern of osteoderms. These anatomical data may indicate how the Baurusuchidae had a wide distribution in Gondwanaland as they were able to move across large distances
Occurrence of Gastroliths in _Baurusuchus_ (Baurusuchidae, Mesoeucrocodylia) from Adamantina Formation, Bauru Basin
The fossil record of Baurusuchidae Mesoeucrocodylia in the General Salgado county and its surroundings is one of the best regarding preservation, completeness and articulation of skull and skeleton remains, including specimens that shown even the most delicate bone structures and cartilaginous tissues. 

One of them, UFRJ DG 288-R, has preserved its skull and about 80% of its skeleton. During the removal of the rock matrix, on what should be the specimen’s abdominal region, together with fragments of gastralia were observed some small well-polished weathered angulous to subrounded clasts, presumed to be gastroliths. 

These xenoliths occur in a restrict cluster, where at least four peeble-sized stones are visible in the surface of the specimen. The texture and fabrics of these rock fragments differs from the surrounding matrix, presenting darker purplish tones. In thin section, one of the fragments revealed isotropic texture, with opaque minerals in abundance, of euhedric to subhedric habits. The mineralogical composition presents mainly clay minerals as weathering products; biotite and chlorite are common, being the last the result of hidratation of the first. Although highly altered, the low quartz content, small-sized and well-formed crystals suggests maphic composition in volcanic context, possibly representing a basalt fragment. 

In extant Crocodyliformes, the occurrence of gastroliths is commonly associated with food processing in the stomach, diving ballast, hunger stress and/or supplementary mineral ingestion. 

As baurusuchids are characterized as medium to large size fully terrestrial predator/scavengers, based on skeletal data, the ballast function of gasthroliths is excluded in this case. As mentioned above, extant crocodyliforms such as _Caiman_ and _Crocodylus_ ingest stones when under stressful conditions of lack of food, water or when in high population density. Osteoderms are one of the primary sources for calcium and a reservoir for the homeostasis. The hunger stress can be observed in the osteoderms histological cuts as an abnormal concentration of osteoclasts at its inner region overwhelming the presence of osteoblasts and consuming the osteocytes. The preservation of osteoderms associated with gasthroliths may reveal if the stone ingestion in baurusuchids is a normal or driven by hunger behavior. 

The paleoenvironmental conditions dominating the Adamantina Formation during the Late Cretaceous are considered mainly arid, marked with strong seasonality, alternating long droughts and short rainy periods, associated with flashflood events. The stressful condition created during the dry season would cause famine and mass mortality, thus forcing animals to endure or escape. The baurusuchids underwent the dry seasons through behavorial responses of self burial and probably stone ingestion, although natural bahavior cannot be eliminated as a cause. 

Financial support provided by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, grant no 305780/2006–9), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Instituto Virtual de Paleontologia/ Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (IVP/FAPERJ, grant no E–26/152.541/2006).

O princípio da co-culpabilidade e sua aplicação no direito penal brasileiro
O presente trabalho de monografia tem como objetivo discutir o princípio da co-culpabilidade, o qual não se encontra positivado no ordenamento jurídico brasileiro, contudo diante das mudanças sociais que ocorrem diariamente na sociedade e da crescente desigualdade social presente no país, deveria ser adotado. A dificuldade de seu reconhecimento, em razão de ser um princípio implícito, causa bastante injustiça, pois pessoas miseráveis que se encontram em situações fáticas diferentes são repreendidas de forma mais rigorosa do que a minoria abastarda da sociedade
Uma proposta de metodologia para diferenciar argumentos e explicações
O objetivo deste trabalho é apresentar uma metodologia para diferenciar Argumentos e Explicações, já que de acordo com Osborne e Patterson (2011) a falta de distinção seria uma fraqueza da área. Também testar desambiguar um trecho de atividade que serviu de exemplo na polêmica entre Berland e McNeill (2012) e Osborne e Patterson (2011-2012) sobre diferenciar Argumentos de Explicações. Distinguir passa por (1) Identificação da conclusão; (2) Análise da intenção da assertiva; (3) Análise da Conclusão; (4) Análise da relação de plausibilidade entre os elementos; (5) Análise da relação entre motivadores. A ferramenta permitiu diferenciar o trecho, assim podendo ser considerada útil para a desambiguação dessas práticas epistêmicas em produções
Nadadores competidores da categoria master : uma abordagem baseada na teoria da prática
Trabalho de Conclusão de Curso (graduação)—Universidade de Brasília, Faculdade de Educação Física, 2016.A natação competitiva máster vem ganhando cada vez mais adeptos. Muitos ex-atletas, atletas que participavam de outras modalidades ou até mesmo indivíduos que buscam a saúde e o esporte aumentam a massa que compõe a natação competitiva dessa categoria. A pesquisa exploratória busca conhecer os elementos e a dinâmica da prática de natação competitiva na categoria máster identificando os padrões e momentos de consumo. Para tanto, optou-se por utilizar como fundamento teórico a “teoria da prática”, tendo em vista que, ao considerar a prática uma unidade social primária, contribui para responder à dualidade entre “estrutura social” e “agência individual”. Foi utilizada a técnica de grupo focal para coletar os dados de maneira a aprofundar o assunto sem ficar restrito às opiniões singulares, onde a discussão dos temas por um conjunto de interessados e envolvidos com a temática enriquece ainda mais as respostas procuradas. O estudo concluiu que a motivação pelo esporte competitivo na modalidade máster é a principal fonte de propósito e significado para os seus praticantes. A competição de maneira prazerosa estimula constantemente a motivação dos praticantes que continuam investindo o seu tempo, energia e recursos financeiros para instigar cada vez mais esse prazer e alcançar seus objetivos pessoais.Competitive master swimming is gaining more and more adepts. Many former athletes, athletes who have participated in other modalities or even individuals seeking health and sport, increase the mass that composes the competitive master swimming in that category. Thus, the exploratory research aims to know the elements and dynamics of competitive swimming practice in master category, identifying patterns and consumption moments. Therefore, we chose to use as theoretical basis the "practice theory", given that, when considering the practice a primary social unit, it contributes to answer the duality between "social structure" and "individual agency". The focus group technique was used to collect data in order to deepen the subject without being restricted to a single person's opinions, in which the discussion of the issues by people interested and engaged with the theme, enriches the sought answers even more. The study concluded that the competitive sport motivation in the master category is the main source of purpose and meaning for the modality practitioners. Thus, the pleasant way of competition constantly stimulates the practitioners' motivation who keep on investing their time, energy and money to instigate even more that pleasure and achieve their personal goals
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