Results 31 to 40 of about 173 (124)
Loss in the making: absence of pelvic fins and presence of paedomorphic pelvic girdles in a Late Devonian antiarch placoderm (jawed stem-gnathostome). [PDF]
Biol Lett, 2018 Within jawed vertebrates, pelvic appendages have been modified or lost repeatedly, including in the most phylogenetically basal, extinct, antiarch placoderms.
Charest F, Johanson Z, Cloutier R.
europepmc +2 more sources
Records of the Australian Museum, 1992 Two new antiarchs are described, from the Late Devonian Hunter Siltstone near Grenfell in south-eastern Australia (Grenfellaspis branagani n.gen., n.sp.), and from the Early Middle Devonian Dayaoshan Group in Guangxi, south-eastern China (Dayaoshania youngi n.gen., n.sp.). New material is described of Xichonolepis qujingensis P'an & Wang, 1978 from the
A. Ritchie +3 more
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Histology of "placoderm" dermal skeletons: Implications for the nature of the ancestral gnathostome. [PDF]
J Morphol, 2013 The vertebrate dermal skeleton has long been interpreted to have evolved from a primitive condition exemplified by chondrichthyans. However, chondrichthyans and osteichthyans evolved from an ancestral gnathostome stem-lineage in which the dermal skeleton
Giles S, Rücklin M, Donoghue PC.
europepmc +2 more sources
, 1984 (Uploaded by Plazi from the Biodiversity Heritage Library) No abstract provided.
Young, Gavin C.
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Mathematical Problems in Engineering, Volume 2020, Issue 1, 2020., 2020 To improve the efficient and precise seeding of potatoes, a novel combination vacuum and spoon belt metering device was designed. The overall structure and working principle of vacuum and spoon belt metering devices were illustrated and analyzed.
Zhang Wanzhi +6 more
wiley +1 more source
Postfire Safety Investigation on Prestressed RPC Beams after Exposure to Elevated Temperatures
Advances in Materials Science and Engineering, Volume 2020, Issue 1, 2020., 2020 Since the postfire safety of prestressed RPC beams after exposure to elevated temperatures needs to be studied and proved, this paper prepares eight smart prestressed RPC beams with intelligent sensors built in to monitor the internal temperature, force, and strain. The residual bearing tests after fire are carried out. The failure process of the beams
Yan Kai +5 more
wiley +1 more source
Stability Mechanism and Repair Method of U‐Shaped Steel Reverse Arch Support in Soft Floor Roadway
Advances in Civil Engineering, Volume 2020, Issue 1, 2020., 2020 This paper is aimed at the inverted arch support instability of track roadway with mining level +1100 m in Liuyuanzi Coal Mine. By means of field investigation, theoretical analysis, numerical calculation, and engineering practice, the instability reasons of inverted arch structure are expounded, the mechanical mechanism of instability of inverted arch
Chao Wang +4 more
wiley +1 more source
Известия высших учебных заведений: Геология и разведка, 2016 The stratigraphie distribution and systematic composition of the Middle-Upper Devonian remains of antiarchs from the sediments of Central Kazakhstan are analyzed. Central Kazakhstan ichthyofauna contains mainly endemic taxons of antiarchs.
S. V. Moloshnikov
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Dataset of antiarch placoderms (the most basal jawed vertebrates) throughout Middle Paleozoic [PDF]
, 2022 Abstract. Antiarch placoderms, the most basal jawed vertebrates, have the potential to enlighten the origin of the last common ancestor of jawed vertebrates. Quantitative study based on credible data is more convincing than qualitative study. To reveal the antiarch distribution in space and time, we created a comprehensive structured dataset of ...
Zhaohui Pan +3 more
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Journal of Palaeogeography, 2020 Middle Palaeozoic vertebrate fossil occurrences are summarised for Australia, with reference to faunal connections between Asia and East Gondwana, as first indicated by fish distributions of Lower Devonian fossil sites. Major endemic groups discussed are
Gavin Charles Young, Jing Lu
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