Search results for "canals"
showing 6 items of 26 documents
L'obra pública en el territori valencià durant la formació de l'estat liberal (1834-1868) : la tasca dels enginyers de camins
2011
La tesi analitza el desenvolupament de les obres públiques a l'Estat espanyol entre 1834 i 1868 centrant-se especialment en el territori valencià. Revisa les principals infraestructures de l'etapa i el treball dels seus projectistes, el Cos d'Enginyers de camins, dins del complexe marc polític, legal i econòmic d'aquests anys. Presta una especial atenció al desenvolupament dels regadius, obres en les que els valencians eren, llavors, capdavanters. This doctoral thesis analyses the development of public works of infrastructure in Spain between 1834 and 1868, paying a special attention to the Valencian territory. Revises the construction of the main infrastructures of this period as well as t…
Apical seal comparison of low-temperature thermoplasticized gutta-percha technique and lateral condensation with two different master cones
2007
Aim: To compare the apical sealing in mesio-buccal canals of extracted molars obturated with low-temperature thermoplasticized gutta-percha or cold lateral condensation techniques using a .06 or a .02 mm/mm tapered gutta-percha master cone. The secondary aim was to evaluate the depth of spreader penetration in root canals using a .06 or a .02 mm/mm tapered gutta-percha master cone. Methodology: Forty-four mesio-buccal curved canals (25-40º) were instrumented with .06 nickel-titanium rotary instruments and randomly distributed into two control groups (n=4) and three experimental groups (n=12) for obturation by the Ultrafil® 3D system or by cold lateral condensation with .06 or .02 tapered ma…
Nonlinear nystagmus processing causes torsional VOR nonlinearity.
2003
The eye movement component that rotates around the line of sight, i.e., the ocular torsion, is in many aspects different from horizontal and vertical eye movements. While ocular torsion is mediated only by reflexive pathways like the torsional vestibulo-ocular and optokinetic reflexes (TVOR and OKN, respectively), horizontal and vertical components are also subject to intentional control mechanisms that are mediated by the saccadic and the pursuit systems. Dynamic properties of torsional eye movements are also very distinct. While horizontal and vertical VOR components show a gain close to unity and a small neural integration leakage with a time constant around pi=30 s, the TVOR shows a sma…
Effect of water immersion on post-rotatory and caloric nystagmus.
1991
Caloric nystagmus and post-rotatory nystagmus were recorded with and without head-out water immersion. As water immersion reduces body weight by about 90% owing to buoyancy, it decreases somatosensory inputs. Thus water immersion can be used to simulate a weightless environment. Caloric nystagmus was enhanced significantly by water immersion; however, post-rotatory nystagmus was not. These findings demonstrate that caloric nystagmus is easily affected by water immersion which decreases somatosensory inputs, but that post-rotatory nystagmus is not.
European vestibular experiments on the Spacelab-1 mission: 1. Overview.
1986
During the flight of Spacelab-1 a series of vestibular experiments was performed on the crew by a group of European investigators. Control experiments were carried out on the same subjects pre- and postflight. The tests included caloric stimulation of the ears, threshold measurements of response to linear acceleration, motion sickness provocative stimuli, vestibulo-ocular reflexes during linear and angular stimulation, estimation of the subjective vertical (luminous line measurements) and static ocular counterrotation at various tilt angles. The caloric experiment proved the existence of a nonthermoconvective mechanism of caloric nystagmus in space. Most of the other test results point to a…
Third canal in the mesial root of permanent mandibular first molars: Review of the literature and presentation of 3 clinical reports and 2 in vitro s…
2007
Introduction. Systematic anatomical studies corroborate the anatomical complexity of the root canal system. Deviations from the norm such as multiple orifices, apical deltas, accessory canals and other variations are frequent. Objectives. To present clinical reports of mandibular molars with three canals in the mesial root and two in vitro studies of the morphology of these canals, together with a review of the literature. Materials and Methods. Three clinical reports are presented of mandibular molars where three canals in the mesial roots were treated endodontically. Two in vitro studies were performed, one using computerized tomography and the other with scanning electron microscopy, to …