Search results for " Traction"
showing 10 items of 20 documents
Vital dyes in macular hole surgery
2021
Currently, surgical techniques, such as internal limiting membrane peeling, are used widely for macular holes, macular puckers, epiretinal membranes, diabetic macular edema, retinal detachment, retinal vein occlusions, vitreomacular traction, optic pit maculopathy, and Terson syndrome. This study aimed to highlight any differences regarding visual acuity and ocular tomography coherence changes after staining the internal limiting membrane with dilutions of Brilliant Blue G vs. lutein/zeaxanthin-based dyes. This study involved 30 eyes of 30 patients who had undergone posterior pole vitrectomy for idiopathic stage 4 macular hole. The study lot was divided in two subgroups, 15 eyes colored wit…
Shade effects on overseeded bermudagrass athletic fields: II. rooting, species composition, and traction
2019
Shade from athletic stadium structures can be a significant detriment to turfgrass performance. The objective of this study was to determine the effects of shade on rooting and playing surface stability, measured as traction, on overseeded or non-overseeded bermudagrass (Cynodon spp.) turf. An experiment was established in 2013 on a mature bermudagrass [Cynodon dactylon (L.) Pers. cv. Riviera] turf that was either overseeded with perennial ryegrass (Lolium perenne L.) or non-overseeded. Shade structures were installed to create four light level treatments, including 0%, 30%, 60%, or 90% light-reducing shade cloth. The light treatments resulted in average daily light integrals (DLI) of 40.8,…
Tuning of Extended Kalman Filters for Sensorless Motion Control with Induction Motor
2019
This work deals with the tuning of an Extended Kalman Filter for sensorless control of induction motors for electrical traction in automotive. Assuming that the parameters of the induction motor-load model are known, Genetic Algorithms are used for obtaining the system noise covariance matrix, considering the measurement noise covariance matrix equal to the identity matrix. It is shown that only stator currents have to be acquired for reaching this objective, which is easy to accomplish using Hall-effect transducers. In fact, the Genetic Algorithm minimizes, with respect to the system covariance matrix, a suitable measure of the displacement between the stator currents experimentally acquir…
Tractional Motion Machines: Tangent-Managing Planar Mechanisms as Analog Computers and Educational Artifacts
2012
Concrete and virtual machines play a central role in the both Unconventional Computing (machines as computers) and in Math Education (influence of artifacts on reaching/producing abstract thought). Here we will examine some fallouts in these fields for the Tractional Motion Machines, planar mechanisms based on some devices used to plot the solutions of differential equations by the management of the tangent since the late 17th century.
Une quête d'exactitude : machines, algèbre et géométrie pour la construction traditionnelle des équations différentielles
2015
In La Géométrie, Descartes proposed a “balance” between geometric constructions and symbolic manipulation with the introduction of suitable ideal machines. In particular, Cartesian tools were polynomial algebra (analysis) and a class of diagrammatic constructions (synthesis). This setting provided a classification of curves, according to which only the algebraic ones were considered “purely geometrical.” This limit was overcome with a general method by Newton and Leibniz introducing the infinity in the analytical part, whereas the synthetic perspective gradually lost importance with respect to the analytical one—geometry became a mean of visualization, no longer of construction. Descartes’s…
Energy and environmental assessment of a traction lithium-ion battery pack for plug-in hybrid electric vehicles
2019
Abstract Traction batteries are a key factor in the environmental sustainability of electric mobility and, therefore, it is necessary to evaluate their environmental performance to allow a comprehensive sustainability assessment of electric mobility. This article presents an environmental assessment of a lithium-ion traction battery for plug-in hybrid electric vehicles, characterized by a composite cathode material of lithium manganese oxide (LiMn2O4) and lithium nickel manganese cobalt oxide Li(NixCoyMn1-x-y)O2. Composite cathode material is an emerging technology that promises to combine the merits of several active materials into a hybrid electrode to optimize performance and reduce cost…
Effects on the maxilla and cranial base caused by cervical headgear : a longitudinal study
2011
Objectives: The aim of this study is to test the possible orthopedic effects of cervical headgear on the cranial base and maxilla. Study design: a sample consisting of 79 subjects with skeletal class II malocclusion was divided into two groups. The experimental group was made up of 41 patients all treated with cervical headgear. The control group included a total of 38 non-treated patients. Each one of these groups was then subdivided according to age into one of three groups: prepubescent, pubescent or post-pubescent. Cephalometric parameters were compared in both groups in order to measure the cranial base angle and the vertical and sagittal position of the maxilla. Additionally, cephalom…
ANATOMICAL AND FUNCTIONAL OUTCOMES OF SYMPTOMATIC IDIOPATHIC VITREOMACULAR TRACTION
2016
To describe the natural history of eyes with symptomatic idiopathic vitreomacular traction (VMT).Retrospective multicenter study of 168 eyes with spectral-domain optical coherence tomography (SD-OCT) findings consistent with idiopathic VMT. All eyes were graded according to SD-OCT findings. Grade 1 was defined as incomplete cortical vitreous separation with foveal attachment. Grade 2 was defined as Grade 1 plus intraretinal cysts or clefts. Grade 3 was defined as Grade 2 plus a foveal detachment. All patients were followed for at least 6 months.There were 168 patients (51 men) with a mean age of 68.8 ± 10.7 years. Patients were followed for a mean of 22.7 ± 20.1 months. The mean duration of…
Painful scar neuropathy: principles of diagnosis and treatment
2015
Nerve-tissue interactions are critical. Peripheral nerve injuries may involve intraneural and extraneural scar formation and affect nerve gliding planes, sometimes leading to complex clinical presentations. All of these pathological entities involve pain as the main clinical symptom and can be subsumed under the term "painful scar neuropathy". The authors review the literature on treatment approaches to peripheral nerve scar neuropathy and the outcomes of neurolysis-associated procedures and propose a simple classification and a therapeutic approach to scar neuropathy. The search retrieved twenty-one papers, twenty of which reported pain reduction or resolution with various techniques. Ther…
Vitrectomía enzimática por inyección intravítrea de plasmina autóloga como tratamiento inicial de las membranas epirretinianas maculares y el síndrom…
2009
espanolObjetivo: Determinar si la inyeccion intravitrea de plasmina es efectiva en el tratamiento de las membranas epirretinianas maculares (MEM) y el sindrome de traccion vitreomacular (STVM), sin necesidad de asociar vitrectomia quirurgica. Material y metodo Diseno: Estudio piloto prospectivo, de intervencion, serie de casos. Pacientes: Siete pacientes, cuatro con membrana epirretiniana macular y tres con sindrome de traccion vitreomacular. Tratamiento: Inyeccion intravitrea de 0,2 ml de plasmina autologa bajo anestesia topica. La plasmina fue obtenida por un metodo simplificado modificado por adiccion de uroquinasa. Principales medidas: Grado de separacion de la membrana epirretiniana de…