Skull morphology of the oldest turtles: a preliminary description ofProganochelys quenstedti

1983 ◽  
Vol 3 (1) ◽  
pp. 25-28 ◽  
Author(s):  
Eugene S. Gaffney ◽  
Lorraine J. Meeker
Keyword(s):  
Skull Morphology ◽  
Preliminary Description

Introduction to methods of describing the forecast on the risk of failure to the means of transport

2012 ◽  
Vol 30 (1) ◽  
pp. 119-127
Author(s):  
Henryk Tomaszek ◽  
Ryszard Kaleta ◽  
Mariusz Zieja
Keyword(s):  
Long Range ◽  
Failure Rate ◽  
Risk Of Failure ◽  
The Relationship ◽  
Preliminary Description

The paper is an attempt to describe the forecast on the risk of damages resulting from failures to the means of transport. It has been assumed that the product of the probability of failure (fault) occurrence and measures of effects thereof are to be used to estimate the risk. The below presented dependences that describe the risk of damages have been based on the failure rate. With the available literature as the basis, a preliminary description of the probability of a failure (fault) and the level of losses has been proposed. The paper gives dependences on short- and long-range risk forecasts. To determine the relationship for the probability of a failure (fault), the failure rate has been used.

scholarly journals The isotopic niche of Atlantic, biting marine mammals and its relationship to skull morphology and body size

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Massimiliano Drago ◽  
Marco Signaroli ◽  
Meica Valdivia ◽  
Enrique M. González ◽  
Asunción Borrell ◽  
...  
Keyword(s):  
Body Size ◽  
Atlantic Ocean ◽  
Fisheries Management ◽  
Marine Mammals ◽  
Trophic Position ◽  
Sympatric Species ◽  
Isotopic Niche ◽  
Apex Predators ◽  
Skull Morphology ◽  
Ecosystem Based Fisheries Management

AbstractUnderstanding the trophic niches of marine apex predators is necessary to understand interactions between species and to achieve sustainable, ecosystem-based fisheries management. Here, we review the stable carbon and nitrogen isotope ratios for biting marine mammals inhabiting the Atlantic Ocean to test the hypothesis that the relative position of each species within the isospace is rather invariant and that common and predictable patterns of resource partitioning exists because of constrains imposed by body size and skull morphology. Furthermore, we analyze in detail two species-rich communities to test the hypotheses that marine mammals are gape limited and that trophic position increases with gape size. The isotopic niches of species were highly consistent across regions and the topology of the community within the isospace was well conserved across the Atlantic Ocean. Furthermore, pinnipeds exhibited a much lower diversity of isotopic niches than odontocetes. Results also revealed body size as a poor predictor of the isotopic niche, a modest role of skull morphology in determining it, no evidence of gape limitation and little overlap in the isotopic niche of sympatric species. The overall evidence suggests limited trophic flexibility for most species and low ecological redundancy, which should be considered for ecosystem-based fisheries management.

scholarly journals Preliminary Description of a New Petrel

The Auk ◽  
1914 ◽  
Vol 31 (1) ◽  
pp. 12-13
Author(s):  
Robert Cushman Murphy
Keyword(s):  
Preliminary Description

All-Trans Retinoic Acid-Induced Craniofacial Malformation Model: A Prenatal and Postnatal Morphological Analysis

2017 ◽  
Vol 54 (4) ◽  
pp. 391-399 ◽  
Author(s):  
Weicai Wang ◽  
Yutao Jian ◽  
Bin Cai ◽  
Miao Wang ◽  
Mu Chen ◽  
...  
Keyword(s):  
Retinoic Acid ◽  
Morphological Analysis ◽  
Bone Development ◽  
Skull Morphology ◽  
Craniofacial Malformations ◽  
Mandibular Incisor ◽  
Craniofacial Bone ◽  
Trans Retinoic Acid ◽  
All Trans Retinoic Acid ◽  
Age Dependent

Objective To characterize the prenatal and postnatal craniofacial bone development in mouse model of all-trans retinoic acid (ATRA) exposure at different ages by a quantitative and morphological analysis of skull morphology. Methods Pregnant mice were exposed to ATRA at embryonic day 10 (E10) and 13 (E13) by oral gavage. Skulls of mice embryos at E19.5 and adult mice at postnatal day 35 (P35) were collected for high-resolution microcomputed tomography (microCT) imaging scanning and section HE staining. Reconstruction and measurement of mouse skulls were performed for prenatal and postnatal analysis of the control and ATRA-exposed mice. Results Craniofacial malformations in mouse models caused by ATRA exposure were age dependent. ATRA exposure at E10 induced cleft palate in 81.8% of the fetuses, whereas the palatine bone of E13-exposed mice was intact. Inhibitions of maxilla and mandible development with craniofacial asymmetry induced were observed at E19.5 and P35. Compared with control and E13-exposed mice, the palatine bones of E10-exposed mice were not elevated and were smaller in dimension. Some E10-exposed mice exhibited other craniofacial abnormalities, including premature fusion of mandibular symphysis with a missing mandibular incisor and a smaller mandible. Severe deviated snouts and amorphous craniofacial suture were detected in E13-exposed mice at P35. Conclusion These morphological variations in E10- and E13-exposed mice suggested that ATRA was teratogenic in craniofacial bone development in mice and the effect was age dependent.

Taxonomy and distribution of the Brazilian species of Thylamys (Didelphimorphia: Didelphidae) / La taxonomie et la distribution des espèces brésiliennes du genre Thylamys (Didelphimorphia: Didelphidae)

Mammalia ◽  
2006 ◽  
Vol 70 (1-2) ◽  
Author(s):  
Ana Paula Carmignotto ◽  
Talitha Monfort
Keyword(s):  
Natural History ◽  
Geographic Distribution ◽  
Taxonomic Status ◽  
Skull Morphology ◽  
Geographic Variations ◽  
Qualitative And Quantitative ◽  
Brazilian Species ◽  
New Information ◽  
Capture Method ◽  
Scientific Collections

AbstractThe recent increase in mammal inventories and the widespread use of pitfall traps as a major capture method in Brazil have increased the number of non-volant small mammal specimens in scientific collections, providing new information on natural history, geographical range, and taxonomic status of many marsupials and rodents. To date, however, little is known about the Brazilian species of the marsupial genus Thylamys : the number of species in the country is disputed, as are their names and geographic distribution. Thus, the aim of this study was to define the Brazilian species of the genus, delimiting their taxonomic status and distributional range. We provide qualitative and quantitative data on external and skull morphology for specimens housed in scientific collections. A study of the material available allowed us to recognize the occurrence of three species in Brazil: Thylamys karimii (Petter, 1968), T. macrurus (Olfers, 1818) and T. velutinus (Wagner, 1842). For each of these we provide redescriptions, a discussion of local and geographic variations, geographic distribution, taxonomy, age class differentiation, sexual dimorphism, and natural history.

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