Search results for "caudal"
showing 10 items of 14 documents
Ecomorphological inferences in early vertebrates: reconstructing Dunkleosteus terrelli (Arthrodira, Placodermi) caudal fin from palaeoecological data
2017
Our knowledge about the body morphology of many extinct early vertebrates is very limited, especially in regard to their post-thoracic region. The prompt disarticulation of the dermo-skeletal elements due to taphonomic processes and the lack of a well-ossified endoskeleton in a large number of groups hinder the preservation of complete specimens. Previous reconstructions of most early vertebrates known from partial remains have been wholly based on phylogenetically closely related taxa. However, body design of fishes is determined, to a large extent, by their swimming mode and feeding niche, making it possible to recognise different morphological traits that have evolved several times in no…
El problema de la descarga del agua subterránea al medio superficial: estudio de esquemas de conocimiento en universitarios
2010
En este trabajo se muestran los resultados de un estudio sobre los esquemas de conocimiento de estudiantes universitarios en relación a la importancia que prestan al agua subterránea para explicar el caudal de un río tras un tiempo sin precipitaciones, así como su integración en sus representaciones gráficas sobre el ciclo del agua. Los resultados indican una importante incultura hidrogeológica de los universitarios, reclamándose la toma de conciencia y formación del profesorado en general en este campo, así como la realización de campañas divulgativas para paliar los problemas que afectan a una adecuada gestión de los recursos hídricos subterráneos.
The pterygoid reflex in man and its clinical application
1992
A technique for eliciting and recording the stretch reflex (R) of the medial pterygoid muscle (Pter) is described. The latency was 6.9 ± 0.43 ms in 23 healthy volunteers (mean age 23.7 years) showing a side-to-side difference of 0.29 ± 0.21 ms. The PterR latencies were little shorter and side-to-side difference little greater than of the masseter reflex. Observations in 5 selected patients with small brainstem lesions suggest that the neurons of the PterR afferents form a cluster within the caudal portion of the trigeminal mesencephalic nucleus. Testing the masseter and pterygoid reflexes provides a more precise localization of small ponto-mesencephalic lesions. © 1992 John Wiley & Sons, In…
Coronella austriaca (Smooth snake) and Zamenis longissimus (Aesculapian Snake) Defensive Behavior
2021
We report for the first time caudal vibrating defensive behavior in Coronella austriaca e Zamenis longissimus
Abdominal-B and caudal inhibit the formation of specific neuroblasts in the Drosophila tail region
2013
The central nervous system of Drosophila melanogaster consists of fused segmental units (neuromeres), each generated by a characteristic number of neural stem cells (neuroblasts). In the embryo, thoracic and anterior abdominal neuromeres are almost equally sized and formed by repetitive sets of neuroblasts, whereas the terminal abdominal neuromeres are generated by significantly smaller populations of progenitor cells. Here we investigated the role of the Hox gene Abdominal-B in shaping the terminal neuromeres. We show that the regulatory isoform of Abdominal-B (Abd-B.r) not only confers abdominal fate to specific neuroblasts (e.g. NB6-4) and regulates programmed cell death of several proge…
Does the Site of Blood Collection in Fish Affect Haematological and Blood Biochemical Results?
2021
The values of haematological and selected blood plasma biochemical parameters of juvenile common carp (Cyprinus carpio Linnaeus, 1758) were compared between blood samples taken from caudal vein and heart to evaluate the influence of blood sampling body site on the obtained results in two groups of fish of different blood sampling order: I – first by caudal and then by cardiac puncture, II – first by cardiac and then by caudal puncture. The obtained results revealed statistically significant (p<0.05) differences only in group I where red blood cell (RBC) count was higher in caudal vein blood, while haematocrit (Ht) value, mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), …
Sirenomelia, case report and review of the literature.
2020
We present a case of sirenomelia diagnosed in the first trimester of pregnancy. The ultrasound examination showed fused lower extremities and an anechoic structure in the lower abdomen that is clue in the early diagnosis. The postmortem study showed the existence of a single umbilical artery (vitelline artery), with an origin in the abdominal aorta. This finding not only explained the presence of a vascular steal with subsequent underdeveloped of pelvic organs, but also differentiated this condition from caudal regression syndrome.
Scalp, basal epidural and intravascular far-field recordings after median nerve stimulation: evidence for a separate N18a potential
2000
Far-field somatosensory evoked potentials (SSEPs) after median nerve stimulation were recorded from scalp- (Fz), epidural- (ED) and intravascular electrodes (basilar artery [Bas]) to study the nature of the controversial N18a component of the widespread N18 potential. In healthy volunteers frequently an N18a potential was recorded at Fz. Simultaneous Fz and ED recordings at the pontomesencephalic junction as well as Bas-recordings at the caudal basilar artery showed N18a components identical in latency and shape. With intravascular recordings the shapes differed between the top of the basilar artery and the caudal artery recordings. These findings support the existence of a separate N18a po…
Ecomorphological inferences in early vertebrates: reconstructing
2017
Our knowledge about the body morphology of many extinct early vertebrates is very limited, especially in regard to their post-thoracic region. The prompt disarticulation of the dermo-skeletal elements due to taphonomic processes and the lack of a well-ossified endoskeleton in a large number of groups hinder the preservation of complete specimens. Previous reconstructions of most early vertebrates known from partial remains have been wholly based on phylogenetically closely related taxa. However, body design of fishes is determined, to a large extent, by their swimming mode and feeding niche, making it possible to recognise different morphological traits that have evolved several times in no…
Las crecidas en ramblas valencianas mediterráneas
2001
This paper takes into account the characterisation of ephemeral stream hydrology from Mediterranean environments. The heavy floods that these countries suffer are due to firstly, the physical watershed features (steep slopes, scarced vegetation cover and thin soils) and, secondly, to the intense and variable rainfall. Large quantities of precipitation fall in a matter of hours, or even minutes, over very steep catchments, causing catastrophic flash-floods, with very pointed hydrographs and short time lags. Using hydrological daily data from the Rambla de la Viuda basin and five-minute data from both Barranc de Carraixet and Rambla de Poyo basins, we have analysed the rainfall- runoff proces…