scholarly journals Jaws of a large belemnite and an ammonite from the Aalenian (Middle Jurassic) of Switzerland

2020 ◽  
Vol 139 (1) ◽  
Author(s):  
Christian Klug ◽  
Walter Etter ◽  
René Hoffmann ◽  
Dirk Fuchs ◽  
Kenneth De Baets

AbstractAlthough belemnite rostra can be quite abundant in Jurassic and Cretaceous strata, the record of belemnite jaws was limited to a few specimens from Germany and Russia. Here, we describe and figure three cephalopod jaws from the Middle Jurassic Opalinus Clay of northern Switzerland. Although flattened, the carbonaceous fossils display enough morphological information to rule out an ammonoid, nautiloid or octobrachian origin of the two larger jaws. Their similarities to belemnite jaws from Germany and Russia conforms with our interpretation of these specimens as belemnite jaws. Based on their rather large size, we tentatively assign these two jaws to the megateuthidid Acrocoelites conoideus. The third jaw is a rather small upper jaw of an ammonoid. Since Leioceras opalinum is by far the most common ammonite in this unit in northern Switzerland, we tentatively suggest that the upper jaw belongs to this species.

2018 ◽  
Vol 69 (8) ◽  
pp. 2191-2196
Author(s):  
Cristian Constantin Budacu ◽  
Nicoleta Ioanid ◽  
Cristian Romanec ◽  
Mihail Balan ◽  
Liliana Lacramioara Pavel ◽  
...  

Canine plays an important role in the dento-maxillary system. From a functional point of view, it provides the canine guidance, by positioning it in the frontal area, has a role in facial aesthetics. It plays an important prosthetic role by having the longest root and one of the longest arcade teeth. Three molars represent the last teeth that erupt in the arches both in the jaw and in the mandible, which is why they remain the most frequently included.Canine incidence is quite common following the wisdom tooth. It can be unilateral or bilateral and is more common in the upper jaw. The canine may remain included at the vestibular, palatal or between the two bones. A separate entity is the incision of the canine in the edentulous mandible or jaw. The study included 213 cases with dento-alveolar pathology, of which 128 patients were selected with dental inclusion. Our study reports that the first three molars are frequent, followed by the canine as opposed to other studies conducted by Guzduz K in 2011 and Fardi A of the same year bringing the canines first (Fardi, Guzduz). Some studies attribute the first place to the superior canine in terms of frequency, but they are abstracted from the molar three inclusion that they consider as most frequently (Compoy). The most common tooth in inclusion is the third molar (lower and upper) followed by the upper canine; the most commonly affected are women for both canine and molar.


Author(s):  
А. . Atyakshev ◽  
N. . Tekoutieva

Extraction of the third molars from the upper jaw can cause somatic dysfunctions and changes in cerebral hemodynamics in patients. Rehabilitation measures aimed to correct somatic dysfunctions and restore cerebral hemodynamics are necessary for these patients.


Zootaxa ◽  
2010 ◽  
Vol 2657 (1) ◽  
pp. 55 ◽  
Author(s):  
RONALD VONK ◽  
DAMIÀ JAUME

A new genus and species of Amphipoda is reported from inland ground waters of the Sultanate of Oman. Although Glyptogidiella omanica gen. et sp. nov. exhibits several features typical of the Bogidiellidae (i. e. combined display of distinct carpal lobe on first gnathopod, reduced pleopodal rami, and unsegmented exopodite of third uropod), its exceptionally large fifth coxal plate and short rami of third uropod do not fit in the restricted diagnosis of the family as recently presented elsewhere. In fact, the enlarged coxal plate V is a feature not reported in any other amphipod, whereas no other bogidiellid displays an expanded basis on pereopod VII. The habitus of Glyptogidiella is not typical for a dweller of a true interstitial niche, with its short antennae, large coxal plate and short and stubby rami on the third uropod. This suggests that the interstitial medium could not be the primary habitat for the species, and that the underground of wadis might contain interstices of large size and could also be in contact with karstic hollows.


1888 ◽  
Vol 43 (258-265) ◽  
pp. 420-423

The brain of Ceratodus has the following general arrangement:—The membrane which represents the pia mater is of great thickness and toughness; there are two regions where a tela choroidea is developed: one where it covers in the fourth ventricle, and the other where it penetrates through the third ventricle and separates the lateral ventricles from each other. The ventricles are all of large size, and the walls of the lateral ventricles are not completed by nervous tissue. The thalamence-phalon and the mesencephalon are narrow, and the medulla oblongata is wide.


1944 ◽  
Vol 80 (1) ◽  
pp. 19-29 ◽  
Author(s):  
Albert Claude

1. Rat tumor extracts, containing chiefly the cytoplasmic constituents of leukemic cells, were fractionated into three main portions, the different components separating in the centrifuge according to size. 2. Mitochondria were isolated by centrifugation at relatively low speed. Elementary composition of purified mitochondria was found to correspond to about 11.5 per cent nitrogen, 1.6 per cent phosphorus, and 27 per cent lipids. Phosphorus and nitrogen content of the lipid portion suggests that as much as 75 to 80 per cent of the lipids of mitochondria is represented by phospholipids. Tests for ribose nucleic acid were positive. 3. Microsomes were separated by means of centrifugation at 18,000 x g. A relation between the high phosphorus content of the microsomes and the marked basophilia of the cytoplasm of leukemic cells is suggested. 4. Phosphorus distribution in the tumor extract, and light absorption analysis of the third fraction, seem to demonstrate that nucleic acid was not present either in a free condition, or in the form of nucleoprotein of relatively low molecular weight. The nature of the results suggests that ribose nucleic acid occurs in the cytoplasm of leukemic cells only in association with formed elements of relatively large size, namely microsomes, and mitochondria.


2012 ◽  
Vol 86 (4) ◽  
pp. 652-658 ◽  
Author(s):  
Andrzej Kaim ◽  
Simon Schneider

Larval and juvenile growth stages of myoconchid bivalves (family Kalenteridae) are illustrated and described for the first time. Excellently preserved shells ofMyoconcha crassaJ. Sowerby, 1824 from the middle Bathonian (Middle Jurassic) clay/silt deposits of southern Poland reveal that the prodissoconch in this taxon is large (exceeding 350 µm in length) and characterized by a prominent, collar-like structure arising from the demarcation to the dissoconch. Similar prodissoconch morphology has not been described previously in any other bivalve genus. The large size and absence of a prodissoconch II strongly suggest a non-planktotrophic development of the larvae, indicating either simple lecithotrophy or long-term brooding and parental care for the larvae in this species. Consequently, the new discovery constitutes the earliest well-documented record of non-planktotrophic development in the Bivalvia. The shell ofMyoconcha crassais composed of an outer cross-lamellar layer and an inner complex cross-lamellar layer. This composition suggests that the Kalenteridae may be included in the Carditida rather than the Palaeoheterodonta or Anomalodesmata. The genusPseudomyoconchaRossi Ronchetti and Allasinaz, 1966 is rejected herein and considered as a junior synonym ofMyoconchaJ. Sowerby, 1824.


2004 ◽  
Vol 287 (5) ◽  
pp. R1190-R1193 ◽  
Author(s):  
Harvey J. Grill ◽  
Jill S. Carmody ◽  
L. Amanda Sadacca ◽  
Diana L. Williams ◽  
Joel M. Kaplan

The central glucagon-like peptide-1 (GLP-1) system has been implicated in the control of feeding behavior. Here we explore GLP-1 mediation of the anorexic response to administration of systemic LPS and address the relative importance of caudal brain stem and forebrain GLP-1 receptor (GLP-1-R) for the mediation of the response. Fourth-intracerebroventricular delivery of the GLP-1-R antagonist exendin-(9–39) (10 μg) did not itself affect food intake in the 24 h after injection but significantly attenuated the otherwise robust (∼60%) reduction in food intake obtained after LPS (100 μg/kg) treatment. This result highlights a role for caudal brain stem GLP-1-R in the mediation of LPS anorexia but does not rule out the possibility that forebrain receptors also contribute to the response. Forebrain contribution was addressed by delivery of the GLP-1-R antagonist to the third ventricle with the caudal flow of cerebrospinal fluid blocked by occlusion of the cerebral aqueduct. Exendin-(9–39) delivery thus limited to forebrain did not attenuate the anorexic response to LPS. These data suggest that LPS anorexia is mediated, in part, by release of the native peptide acting on GLP-1-R within the caudal brain stem.


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