130 research outputs found

    A protosuchid crocodilian from the Forest Sandstone Formation (Upper Karoo) of Zimbabwe

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    Main articleA protosuchid crocodilian is reported from the Forest Sandstone Formation (Upper Triassic) of the central Zambezi Valley, Zimbabwe. It is closely related to known protosuchians from terminal Karoo deposits in South Africa and it is provisionally referred to cf. Notochampsa sp.Non

    Coaxing history from the rocks: The contribution of the BPI (palaeontology)

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    NoneFrom humble beginnings at the conclusion of the Second World War, the Bernard Price Institute for Palaeontological Research has developed into a major centre of palaeontological research and training whose contribution extends far beyond the borders of South Africa. Over the 50 years of its existence it has amassed large collections offossils from most of the fossiliferous deposits of South Africa, covering a large segment of geological time and a broad sweep of the diversity oflife. These collections have provided the foundation for ongoing research by its staff and students, as well as by visiting scientists from many other parts of the world. As a component of the University of the Witwatersrand, the Institute incorporates the only separate teaching department of palaeontology in any South African university, through which a steady stream of undergraduate and graduate students has passed over the years. Many of those students now occupy senior research and management positions in institutions and corporations scattered across the world. Under its current leadership, the Institute looks set fair for the next 50 years of solid contribution to world palaeontology.Non

    Preliminary report of a large theropod dinosaur trackway in Clarens Formation sandstone (Early Jurassic) in the Paul Roux district, northeastern Free State, South Africa

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    An isolated fallen block of Clarens Formation sandstone near the small northeastern Free State town of Paul Roux preserves part of the trackway of a bipedal dinosaur. Although well known as a local curiosity, this trackway has not previously been formally reported or described. It consists of five successive paces of what is interpreted as a medium-sized to large theropod dinosaur, and represents the largest known theropod trackway in the ‘Stormberg’ sequence in South Africa. The tracks are assigned to the ichnotaxon Grallator sp., and show similarities to North American tracks of comparable age originally described as Dilophosauripus. Until now no body fossils of a likely candidate trackmaker were known, but elsewhere in this volume a possible candidate is described by the second author

    The anatomy of the triassic theropod Syntarsus rhodesiensis (Saurischia : Podokesauridae) and a consideration of its biology

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    The osteology of the Upper Triassic podokesaurid Syntarsus rhodesiensis is described, based on a series of 30+ individuals representing all skeletal elements, recovered since the description of the holotype (Raath, 1969). A brief account of the geology of the finds is given, with an attempt at a reconstruction of the palaaoenvironment. The excellence of preservation of the bones has permitted an attempt at the restoration of soft tissues including the brain, cranial nerves, main cranial blood vessels and the musculature of the jaws, neck and limbs. Histological sections of limb bones have shown that the compact bone was highly vascular, and this, together with the structure of the brain, palaeoenvironmental considerations, social behaviour and group structure, leads to the conclusion that Syntarsus was an endothermic homeotherm inhabiting a hot arid region at the end of the Triassic, with a social organisation into "flocks" in which females predominated numerically. Clear evidence of sexual dimorphism is presented. Syntarsus is reconstructed as a bipedal, saltatorial predator which differs in subtle, but probably generically significant, characteristics from the closely related North American genus, Coelophysis. Its anatomy characterises it as a medium-sized agile animal with a highly kinetic skull; incipiently opposable pollex in the raptorial manus; highly cursorial hindlimb; and with features in the dentition and hallux which suggest a grooming function. It is concluded that the Triassic coelurosaurian stock provided an advanced and well adapted base from which the successful coelurosaur radiation into the later Mesozoic sprang, and that this stock was physiologically pre-adapted for the emergence of the avian (and possibly the pterosaur) lineages in the Jurassi

    First record of Triassic Rhynchosauria (Reptilia: Diapsida) from the Lower Zambezi Valley, Zimbabwe

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    True rhynchosaurids are described from Zimbabwe for the first time. The fossils occur as partially associated skeletons and scattered isolates in upward-fining, micaceous fluvial sandstones of the Pebbly Arkose Formation (late Triassic) in the Western Cabora Bassa Basin, Lower Zambezi Valley. On the grounds that the dentary of the Zimbabwean form possesses a row of small, conical lingual teeth in addition to a palisade row of penicillate teeth on the occlusal surface, it is concluded that the taxon present is Hyperodapedon sp., and that it is closely related to a rhynchosaurid described from Tanzania. One bone identified as a prosauropod dinosaurian femur was found associated with the Zimbabwean rhynchosaurids. The late Triassic age suggested by the presence of advanced rhynchosaurids is supported by the occurrence of the typical Triassic fossil plant genus Dicroidium, and by the general stratigraphy of the beds which contain the fossils (i.e. the fossil-bearing beds are underlain by beds of mid-Triassic age or younger, and are overlain by beds of latest Triassic or early Jurassic age

    Effect of Weld Schedule on the Residual Stress Distribution of Boron Steel Spot Welds

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    Press-hardened boron steel has been utilized in anti-intrusion systems in automobiles, providing high strength and weight-saving potential through gage reduction. Boron steel spot welds exhibit a soft heat-affected zone which is surrounded by a hard nugget and outlying base material. This soft zone reduces the strength of the weld and makes it susceptible to failure. Additionally, different welding regimes lead to significantly different hardness distributions, making failure prediction difficult. Boron steel sheets, welded with fixed and adaptive schedules, were characterized. These are the first experimentally determined residual stress distributions for boron steel resistance spot welds which have been reported. Residual strains were measured using neutron diffraction, and the hardness distributions were measured on the same welds. Additionally, similar measurements were performed on spot welded DP600 steel as a reference material. A correspondence between residual stress and hardness profiles was observed for all welds. A significant difference in material properties was observed between the fixed schedule and adaptively welded boron steel samples, which could potentially lead to a difference in failure loads between the two boron steel welds

    A core outcome domain set for clinical research on capillary malformations (the COSCAM project):an e-Delphi process and consensus meeting

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    BACKGROUND: There is limited evidence on the best available treatment options for capillary malformations (CMs), mainly due to the absence of uniform outcome measures in trials on therapies. A core outcome set (COS) enables standard reporting of trial outcomes, which facilitates comparison of treatment results. OBJECTIVES: To develop a core outcome domain set (CDS), as part of a core outcome set (COS), for clinical research on CMs. METHODS: Sixty‐seven potentially relevant outcome subdomains were recognized based on the literature, focus group sessions, and input from the COSCAM working group. These outcome subdomains were presented in an online Delphi study to CM experts (medical specialists and authors of relevant literature) and (parents of) patients with CM (international patient associations). During three e‐Delphi study rounds, the participants repeatedly scored the importance of these outcome subdomains on a seven‐point Likert scale. Participants could also propose other relevant outcome subdomains. Consensus was defined as ≥ 80% agreement as to the importance of an outcome subdomain among both stakeholder groups. The CDS was finalized during an online consensus meeting. RESULTS: In total 269 participants from 45 countries participated in the first e‐Delphi study round. Of these, 106 were CM experts from 32 countries, made up predominantly of dermatologists (59%) and plastic surgeons (18%). Moreover, 163 (parents of) patients with CM from 28 countries participated, of whom 58% had Sturge–Weber syndrome. During the two subsequent e‐Delphi study rounds, 189 and 148 participants participated, respectively. After the entire consensus process, consensus was reached on 11 outcome subdomains: colour/redness, thickness, noticeability, distortion of anatomical structures, glaucoma, overall health‐related quality of life, emotional functioning, social functioning, tolerability of intervention, patient satisfaction with treatment results, and recurrence. CONCLUSIONS: We recommend the CDS to be used as a minimum reporting standard in all future trials of CM therapy. Our next step will be to select suitable outcome measurement instruments to score the core outcome subdomains. What is already known about this topic? Besides physical and functional sequelae, capillary malformations (CMs) often cause emotional and social burden. The lack of uniform outcome measures obstructs proper evaluation and comparison of treatment strategies. As a result, there is limited evidence on the best available treatment options. The development of a core outcome set (COS) may improve standardized reporting of trial outcomes. What does this study add? A core outcome domain set (CDS), as part of a COS, was developed for clinical research on CMs. International consensus was reached on the recommended core outcome subdomains to be measured in CM trials: colour/redness, thickness, noticeability, distortion of anatomical structures, glaucoma, overall health‐related quality of life, emotional functioning, social functioning, tolerability of intervention, patient satisfaction with treatment results, and recurrence. This CDS enables the next step in the development of a COS, namely to reach consensus on the core outcome measurement instruments to score the core outcome subdomains. What are the clinical implications of this work? The obtained CDS will facilitate standardized reporting of treatment outcomes, thereby enabling proper comparison of treatment results. This comparison is likely to provide more reliable information for patients about the best available treatment options

    The Role of Transformation in Learning and Education for Sustainability

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    Education research has acknowledged the value of transformation, which offers an opportunity for researching and rethinking how appropriate and successful educational practices may be. However, despite the role of transformation in higher education and particularly in sustainability learning, there is a paucity of studies which examine the extent to which transformation and learning on matters related to sustainable development may be integrated. Based on this perceived research need, the purpose of this article is to present how transformation in learning in education for sustainability requires the commitment of Faculty and the engament of students. To do this, a set of qualitative case studies were used in higher education institutions across seven countries (Brazil, Serbia, Latvia, South Africa, Spain, Syria, UK). The findings revealed that the concept of education for sustainable development has not been sufficiently integrated into the concept of transformation in higher education institutions. It also found that to enhance sustainability in the curricula, academics should develop collaborative approaches, and discuss how to redesign their own disciplines, and how to appreciate the epistemology and multicultural vision of sustainability, both as a topic, and as a field of education research. It was further found that reflections of the academics on their own values are crucial for developing the transformative potential of students as agents of a sustainable future. It is necessary that universities should transform to serve as models of social justice and environmental stewardship, and to foster sustainability learning
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