scholarly journals A new lower actinopterygian fish from the Upper Mississippian Bluefield Formation of West Virginia, USA

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5533
Author(s):  
Kathryn E. Mickle
Keyword(s):  
West Virginia ◽  
Three Dimensional ◽  
Morphological Features ◽  
New Taxon ◽  
Anterior Border ◽  
Caudal Fin ◽  
Body Fossil ◽  
Bluefield Formation

The Upper Mississippian Bluefield Formation of the Mauch Chunk Group in southeastern West Virginia is known for its preservation of a variety of invertebrate taxa and early tetrapod trackways, but no lower actinopterygian remains have been formally described from these Carboniferous rocks. Here, the first lower actinopterygian fish is described from the Bluefield Formation of West Virginia. This fish is represented by a nearly complete articulated specimen with a three-dimensional snout and an unobstructed view of the gular and branchiostegal region. This new taxon is defined by a unique set of characters, which include features of the snout, circumorbital series, cheek, and operculo-gular region. These features make this fish different and distinct from previously described Carboniferous fishes. Some of the morphological features of note include the presence of a distinct lacrimal, premaxillary, ventral rostral and dorsal rostral bones, a narrow infraorbital ventral to the orbit, and a large crescent shaped infraorbital that contacts a single dermosphenotic. There is an anteriorly inclined hatchet-shaped preoperculum and six small suborbital bones anterior to the expanded region of this bone that filling the space between the preoperculum, dermosphenotic, and infraorbital. Posterior to the preoperculum, there is a single wedge-shaped dermohyal and a series of three rectangular anteopercular bones. The anteopercular bones extend halfway down the anterior border of the rectangular operculum. A median gular, two pairs of lateral gulars, and at least eight branchiostegal rays are present. The heterocercal caudal fin is deeply cleft and inequilobate. The scales have pectinated posterior margins and bear diagonal ridges of ganoine. The description of this new taxon represents the first actinopterygian and the first vertebrate body fossil described from the Bluefield Formation and the second actinopterygian taxon described from the Mauch Chunk Group in West Virginia.

scholarly journals Hadrocheilus ( Lozovskia) - a new subgenus of rhyncholites from the Upper Barremian deposits of South-Western Crimea

2018 ◽  
pp. 69-71
Author(s):  
V. N. Komarov ◽  
E. S. Gaponenko ◽  
M. S. Tarasov
Keyword(s):  
Dorsal Side ◽  
Morphological Features ◽  
New Taxon ◽  
New Subgenus

A new subgenus of Upper Barremian rhyncholites Hadrocheilus (Lozovskia) has been described. It differs from subgenus Hadrocheilus (Microbeccus) Shimansky et Nerodenko by much smaller size of the hood, as well as by the top of the handle, which is significantly raised over the hood, and by the flat dorsal side of the arm. Morphological features of the new taxon allow us to consider it to be an ancestral to Aptian genus Erlangericheilus, the most important feature of which is the transformation of the hood in a small tusk-shaped appendage.

scholarly journals A Method for Evaluating Three-Dimensional Morphological Features: A Case Study Using Marchantia polymorpha

2019 ◽  
Vol 10 ◽  
Author(s):  
Tomoyuki Furuya ◽  
Yoshitaka Kimori ◽  
Hirokazu Tsukaya
Keyword(s):  
Three Dimensional ◽  
Morphological Features ◽  
Marchantia Polymorpha

Dexamethasone-dependent versus -independent markers of epithelial to mesenchymal transition in primary hepatocytes

2010 ◽  
Vol 391 (1) ◽  
Author(s):  
Patricio Godoy ◽  
Sumathi Lakkapamu ◽  
Markus Schug ◽  
Alexander Bauer ◽  
Joanna D. Stewart ◽  
...  
Keyword(s):  
Epithelial To Mesenchymal Transition ◽  
Culture Media ◽  
Three Dimensional ◽  
Morphological Features ◽  
Collagen Gels ◽  
Mesenchymal Transition ◽  
Subsequent Step ◽  
Twist 1 ◽  
Emt Markers

Abstract Recently, epithelial to mesenchymal transition (EMT) has been shown to represent a feature of dedifferentiating hepatocytes in vitro. Three-dimensional soft collagen gels can antagonize but not completely abolish this effect. Hormonal additives to culture media are known to maintain differentiated hepatocyte functions. Therefore, we studied whether insulin and dexamethasone antagonize EMT in cultured hepatocytes. Both hormones antagonized but not completely abolished certain morphological features of EMT. Dexamethasone antagonized acquisition of fibroblastoid shape, whereas insulin favored bile canaliculi formation. In a subsequent step, we analyzed expression of a battery of EMT-related genes. Of all markers tested, vimentin and snail-1 correlated best with morphological features of EMT. Interestingly, dexamethasone reduced expression levels of both vimentin and snail-1, whereas the influence of insulin was less pronounced. An important result of this study is that 12 out of 17 analyzed EMT markers were transcriptionally influenced by dexamethasone (vimentin, snail-1, snail-2, HNF4α, Twist-1, ZEB2, fibronectin, occludin, MMP14, claudin-1, cytokeratin-8, and cytokeratin-18), whereas the remaining factors seemed to be less dependent on dexamethasone. In conclusion, EMT markers in hepatocytes can be classified as dexamethasone-dependent versus -independent.

scholarly journals Unusual lizard fossil from the Miocene of Nebraska and a minimum age for cnemidophorine teiids

2020 ◽  
Vol 7 (8) ◽  
pp. 200317 ◽  
Author(s):  
Simon G. Scarpetta
Keyword(s):  
North America ◽  
Fossil Record ◽  
Fission Track ◽  
Divergence Time ◽  
Morphological Features ◽  
New Taxon ◽  
Fossil Material ◽  
Minimum Age ◽  
North And South America ◽  
North And South

Teiid lizards are well represented in the fossil record and are common components of modern ecosystems in North and South America. Many fossils were referred to the cnemidophorine teiid group (whiptails, racerunners and relatives), particularly from North America. However, systematic interpretations of morphological features in cnemidophorines were hampered by the historically problematic taxonomy of the clade, and the biogeography and chronology of cnemidophorine evolution in North America is poorly understood from the fossil record. Few fossil cnemidophorines were identified with an apomorphy-based diagnosis, and there are almost no fossil cnemidophorines that could be used to anchor node calibrations. Here, I describe a cnemidophorine from the Miocene Ogallala Group of Nebraska and diagnose the fossil using apomorphies. In that process, I clarify the systematic utility of several morphological features of cnemidophorine lizards. I refer the fossil to the least inclusive clade containing Aspidoscelis , Holcosus and Pholidoscelis . The most conservative minimum age of the locality of the fossil is a fission-track date of 6.3 Ma, but mammal biochronology provides a more refined age of 9.4 Ma, which can be used as a minimum age for the crown cnemidophorine clade in divergence time analyses. The fossil indicates that a cnemidophorine lineage that does not live in Nebraska today inhabited the area during the Miocene. I refrain from naming a new taxon pending discovery of additional fossil material of the lineage to which the fossil belonged.

scholarly journals Distrionella coxiana, a new fragilarioid diatom species (Bacillariophyceae) from Tierra del Fuego, Patagonia, Argentina

2019 ◽  
Vol 152 (2) ◽  
pp. 385-391
Author(s):  
Valeria Casa ◽  
Gabriela Mataloni ◽  
Bart Van de Vijver
Keyword(s):  
Typical Feature ◽  
Morphological Features ◽  
Tierra Del Fuego ◽  
New Taxon ◽  
Diatom Species ◽  
Unique Combination ◽  
Diatom Flora ◽  
Electron Microscopical ◽  
Scanning Electron ◽  
Freshwater Diatom

Background and aims – A few years ago, a new survey started of the freshwater diatom flora from peatbogs of Tierra del Fuego (southern Argentina). During this survey, an unknown fragilarioid diatom belonging to the genus Distrionella that could not be identified using the currently available literature was discovered. Methods – Using both Light Microscopical and Scanning Electron Microscopical techniques, the morphology of the unknown Distrionella species has been analysed. The new taxon is properly described, illustrated and compared with all other possible similar Distrionella taxa, known worldwide. Key results – Distrionella coxiana possesses a unique combination of morphological features that excludes conspecificity with all other members of the genus; it is characterized in having narrow, linear valves with small, capitate apices. Transapical ribs, a typical feature of the genus Distrionella, are only weakly developed. One rimoportula is observed close to the apices. Both apices have well-developed apical porefields. The girdle bands bear one complete row of poroids often accompanied by a second, incomplete row of small poroids. Notes on the occurrence and ecology of the new taxon are added.

scholarly journals Plaque morphology in acute symptomatic intracranial atherosclerotic disease

2020 ◽  
pp. jnnp-2020-325027
Author(s):  
Thomas W Leung ◽  
Li Wang ◽  
Xinying Zou ◽  
Yannie Soo ◽  
Yuehua Pu ◽  
...  
Keyword(s):  
Ischaemic Stroke ◽  
Three Dimensional ◽  
Morphological Features ◽  
Atherosclerotic Disease ◽  
Sensitivity Analyses ◽  
Plaque Morphology ◽  
Stroke Subtype ◽  
Anterior Circulation ◽  
Intracranial Atherosclerotic Disease ◽  
Ulcerative Lesions

BackgroundIntracranial atherosclerotic disease (ICAD) is globally a major ischaemic stroke subtype with high recurrence. Understanding the morphology of symptomatic ICAD plaques, largely unknown by far, may help identify vulnerable lesions prone to relapse.MethodsWe prospectively recruited patients with acute ischaemic stroke or transient ischaemic attack attributed to high-grade ICAD (60%–99% stenosis). Plaque morphological parameters were assessed in three-dimensional rotational angiography, including surface contour, luminal stenosis, plaque length/thickness, upstream shoulder angulation, axial/longitudinal plaque distribution and presence of adjoining branch atheromatous disease (BAD). We compared morphological features of smooth, irregular and ulcerative plaques and correlated them with cerebral ischaemic lesion load downstream in MRI.ResultsAmong 180 recruited patients (median age=60 years; 63.3% male; median stenosis=75%), plaque contour was smooth (51 (28.3%)), irregular (101 (56.1%)) or ulcerative (28 (15.6%)). Surface ulcers were mostly at proximal (46.4%) and middle one-third (35.7%) of the lesions. Most (84.4%) plaques were eccentric, and half had their maximum thickness over the distal end. Ulcerative lesions were thicker (medians 1.6 vs 1.3 mm; p=0.003), had steeper upstream shoulder angulation (56.2° vs 31.0°; p<0.001) and more adjoining BAD (83.3% vs 57.0%; p=0.033) than non-ulcerative plaques. Ulcerative plaques were significantly associated with coexisting acute and chronic infarcts downstream (35.7% vs 12.5%; adjusted OR 4.29, 95% CI 1.65 to 11.14, p=0.003). Sensitivity analyses in patients with anterior-circulation ICAD lesions showed similar results in the associations between the plaque types and infarct load.ConclusionsUlcerative intracranial atherosclerotic plaques were associated with vulnerable morphological features and had a higher cumulative infarct load downstream.

scholarly journals Application of 3D Computed Tomography Reconstruction Images to Assess the Thickness and Dimensions of the Posterior Palatal Seal Area

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Soeun Lim ◽  
Seoung-Jin Hong ◽  
Joo-Young Ohe ◽  
Janghyun Paek
Keyword(s):  
Computed Tomography ◽  
3D Model ◽  
Three Dimensional ◽  
Ct Images ◽  
Anterior Border ◽  
Lateral Direction ◽  
Mean Dimension ◽  
The Mean ◽  
The Right ◽  
Palatal Mucosa

Few studies have been reported on the scientific measurements of the thickness and dimensions of the posterior palatal seal (PPS) area. The purpose of this study is to measure and analyze the thickness of palatal mucosa by using a three-dimensional (3D) model reconstructed with computed tomography (CT) images and to present objective values by identifying the PPS area. The CT images were reconstructed as a 3D model by separating the maxillary palate mucosa and teeth. Each reconstructed model was analyzed and the thickness was measured at 93 crossing points of each divided plane. The dimension of the PPS area was measured and the right and left dimensions of the PPS area were compared. The thickness of the palatal mucosa was thicker toward the posterior area. The thickness increased in the lateral direction and decreased again. In the PPS area, the mean dimension between the rearmost of anterior border and the most posterior line was 2.19 mm and the mean dimension between the forefront of anterior border and the most posterior line was 5.19 mm in the right side and 5.16 mm in the left side. The mean dimension from the center of the palate to the right most forward point was 6.85 mm, and the left was 7.36 mm. The new measurement method of palatal mucosal thickness is noninvasive, accurate, and easy to store and study, so it can be used effectively in planning and manufacturing the maxillary complete denture in the digital workflows.

Melanoleuca kashmirensis sp. nov. in subg. Urticocystis from Pakistan

Phytotaxa ◽  
2020 ◽  
Vol 434 (1) ◽  
pp. 89-100
Author(s):  
ZIA ULLAH ◽  
RUBAB KHURSHED ◽  
MUHAMMAD BINYAMIN KHAN ◽  
ISRAR AHMAD ◽  
SANA JABEEN ◽  
...  
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Morphological Characters ◽  
Morphological Features ◽  
New Taxon ◽  
Line Drawings ◽  
Phylogenetic Data ◽  
Molecular Phylogenetic ◽  
A New Species ◽  
Molecular Phylogenetic Data

During this investigation, a new species of Melanoleuca subg. Urticocystis with urticiform cheilocystidia is proposed. The identification is based on morphological characters and molecular phylogenetic analyses using ITS and 28S sequences. A comparison of the morphological features and molecular phylogenetic data with the taxa of subg. Urticocystis confirms the identity of the species as a new taxon. The detailed descriptions, line drawings and phylogenetic results are given.

scholarly journals The morphological features of different Schatzker types of tibial plateau fractures: a three-dimensional computed tomography study

2016 ◽  
Vol 11 (1) ◽  
Author(s):  
Pengbo Chen ◽  
Hao Shen ◽  
Wei Wang ◽  
Binbin Ni ◽  
Zhiyuan Fan ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Tibial Plateau ◽  
Three Dimensional ◽  
Morphological Features ◽  
Tibial Plateau Fractures
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