Search results for "Crania"
showing 10 items of 885 documents
Late Miocene remains from Venta del Moro (Iberian Peninsula) provide further insights on the dispersal of crocodiles across the late Miocene Tethys
2020
The dispersal of Crocodylus from Africa to Europe during the Miocene is not well understood. A small collection of cranial fragments and postcranial elements from the latest Miocene (6.2 Ma) site of Venta del Moro (Valencia, Spain) have previously been referred to Crocodylus cf. C. checchiai Maccagno, 1947 without accompanying descriptions. Here we describe and figure for the first time the crocodylian remains from Venta del Moro, which represent at least two individuals. Our comparisons indicate that this material clearly does not belong to Diplocynodon or Tomistoma - the only two other crocodylians described so far for the European late Miocene. The material is only tentatively referred t…
Controlled feeding experiments with diets of different abrasiveness reveal slow development of mesowear signal in goats ( Capra aegagrus hircus )
2018
ABSTRACT Dental mesowear is applied as a proxy to determine the general diet of mammalian herbivores based on tooth-cusp shape and occlusal relief. Low, blunt cusps are considered typical of grazers and high, sharp cusps typical of browsers. However, how internal or external abrasives impact mesowear, and the time frame the wear signature takes to develop, still need to be explored. Four different pelleted diets of increasing abrasiveness (lucerne, grass, grass and rice husks, and grass, rice husks and sand) were fed to four groups of a total of 28 adult goats in a controlled feeding experiment over a 6-month period. Tooth morphology was captured by medical CT scans at the beginning and end…
Observations on the postcranial anatomy of Hoplitomeryx (Mammalia, Ruminantia, Hoplitomerycidae) from the Miocene of the Apulia Platform (Italy)
2016
The untypical ruminants of the Apulia Platform (central and southeastern Italy), originally accommodated in the genus Hoplitomeryx, have been recently revised. The Scontrone (Abruzzo, central Italy) representatives were included in a new genus, Scontromeryx, with the addition of a new species, Scontromeryx mazzai. In contrast, the Gargano ones were left in Hoplitomeryx, but also in this case with the addition of three new species, Hoplitomeryx devosi, H. macpheei, and H. kriegsmani, described on postcranial remains and based on body mass calculations and using a size class scoring technique. The results of the present study show that Scontromeryx is invalid, that S. mazzai is imperfectly de…
Cranial suture biomechanics inMetoposaurus krasiejowensis(Temnospondyli, Stereospondyli) from the upper Triassic of Poland
2019
Cranial sutures connect adjacent bones of the skull and play an important role in the absorption of stresses that may occur during different activities. The Late Triassic temnospondyl amphibian Metoposaurus krasiejowensis has been extensively studied over the years in terms of skull biomechanics, but without a detailed description of the function of cranial sutures. In the present study, 34 thin sections of cranial sutures were examined in order to determine their histovariability and interpret their biomechanical role in the skull. The histological model was compared with three-dimensional-finite element analysis (FEA) simulations of the skull under bilateral and lateral biting as well as …
The discrepancy between morphological and microanatomical patterns of anamniotic stegocephalian postcrania from the Early Permian Briar Creek Bonebed…
2015
Abstract The histological framework of thirteen Early Permian tetrapod long bones from a single locality, the Briar Creek Bonebed in Archer County, Texas, USA, is described from a series of transverse sections through the midshafts. The bones were morphologically categorized and belong to one of three taxa: Eryops, Archeria, and Diadectes. However, five histotypes are recognized. The first category includes the juvenile bone. The second histotype is characterized by the presence of radial vascular canals. The third histotype is characterized by the numerous longitudinal canals arranged in regular rows. In the fourth histotype, there is strong remodeling in the deep part of the cortex, creat…
Cranial crassicaudiasis in two coastal dolphin species from South Africa is predominantly a disease of immature individuals.
2020
Crassicauda spp. (Nematoda) infest the cranial sinuses of several odontocetes, causing diagnostic trabecular osteolytic lesions. We examined skulls of 77 Indian Ocean humpback dolphins Sousa plumbea and 69 Indo-Pacific bottlenose dolphins Tursiops aduncus, caught in bather-protecting nets off KwaZulu-Natal (KZN) from 1970-2017, and skulls of 6 S. plumbea stranded along the southern Cape coast in South Africa from 1963-2002. Prevalence of cranial crassicaudiasis was evaluated according to sex and cranial maturity. Overall, prevalence in S. plumbea and T. aduncus taken off KZN was 13 and 31.9%, respectively. Parasitosis variably affected 1 or more cranial bones (frontal, pterygoid, maxillary …
A Brief Review of Manufacturing Medical Implants by Single Point Incremental Forming
2018
Abstract SPIF is a relatively new process that can replace conventional deformation processes. Due to the use of generic tools only, the process is suited to achieving unique production or prototypes. The paper presents a brief literature review on current research of single point incremental forming with applications in obtaining medical implants regarding materials and metodology used.
Overview of the History of the Cranial Nerves: From Galen to the 21st Century
2018
Throughout history the description and classification of the cranial nerves has been linked to the development and characteristics of anatomy and the role that it played as a tool in providing rationality to medicine, together with social, cultural, religious, and philosophical factors. Anatomists were interested in the cranial nerves, but they disagreed on their number and their paths. We can divide the history of the cranial nerves into three different periods: the first, early or macroscopic period; the second or microscopic period; and the third period or ontogenesis and genoarchitecture. The main aim of this article is to show how the description and knowledge of the cranial nerves wer…
Intracortical facilitation within the migraine motor cortex depends on the stimulation intensity. A paired-pulse TMS study
2018
Abstract Introduction Connectivity within the primary motor cortex can be measured using the paired-pulse transcranial magnetic stimulation (TMS) paradigm. This evaluates the effect of a first conditioning stimulus on the motor evoked potential (MEP) elicited by a second test stimulus when different interstimulus intervals are used. Aim of the present study was to provide, in patients suffering from migraine without aura (MwoA), additional information on intracortical facilitation (ICF), short intracortical inhibition (SICI), and long intracortical inhibition (LICI), using different intensities of the test stimulus (TS). Methods We enrolled 24 patients with episodic MwoA and 24 age- and sex…
High-definition transcranial direct current stimulation to both primary motor cortices improves unimanual and bimanual dexterity.
2017
While most research on brain stimulation with transcranial direct current stimulation (tDCS) targets unimanual motor tasks, little is known about its effects on bimanual motor performance. This study aims to investigate the effects of tDCS on unimanual as well as bimanual motor dexterity. We examined the effects of bihemispheric anodal high-definition tDCS (HD-atDCS) on both primary motor cortices (M1) applied concurrent with unimanual and bimanual motor training. We then measured the effects with the Purdue Pegboard Test (PPT) and compared them to a sham stimulation. Between a pretest and posttest, 31 healthy, right-handed participants practiced the PPT on three consecutive days and receiv…