1,673 research outputs found

    ASSESSING ADMINISTRATION CHARGES FOR THE AFFILIATE IN INDIVIDUAL ACCOUNT SYSTEMS

    Get PDF
    In any pension system based on capitalization, affiliates have to cover certain explicit costs which in a pay-as-you-go system would be implicit. In this paper we set out a model based on Whitehouse (2000) and Diamond (1999) to enable the explicit costs borne by the affiliate both during his working life and his retirement period to be assessed. It also shows the relationships between the different ways of measuring the costs that make up the total price finally paid by the contributors. Included in the model is the notable effect that some factors -such as gaps in contribution profiles, account transfers and changes in salary profiles- have on projecting the costs borne by the affiliates. Finally we carry out an international comparison of administration costs from the point of view of the affiliate, focusing special attention on the countries of Latin America and Spain. This has a double objective: 1.- To test the validity of criticisms made by some researchers as to whether the new capitalization systems introduced in Latin America are too expensive to run for the affiliates. 2.- To serve as a reference for the individual pension scheme system in Spain. En un sistema de pensiones basado en la capitalización los afiliados deben hacer frentea unos costes explícitos que en el sistema de reparto son implícitos. En este trabajo sedesarrolla un modelo, basado en Whitehouse (2000) y Diamond (1999), que permite evaluarlas comisiones explícitas que soporta el afiliado, tanto durante la vida laboral como durante laetapa de jubilación y que, además, muestra la relación entre las diferentes medidas de loscostes que integran el precio total que finalmente pagan los cotizantes. En el modelo seintroduce el efecto de algunos aspectos que tienen una repercusión muy importante en laproyección de los costes que soportan los afiliados: ¿vacíos¿ en los perfiles de aportación,efecto de los traspasos de fondos y cambio en los perfiles de salarios. Por último, se realizauna comparación internacional de los costes de administración desde la óptica de los afiliadoscon un doble objetivo:1.-Contrastar la validez de la crítica realizada por algunos investigadores a los nuevossistemas de capitalización individual implantados en América Latina, en el sentido de que sonexcesivamente caros de gestionar para los afiliados.2.-Servir de referencia para el sistema de planes de pensiones individuales en España.Capitalización, Costes de Administración, Fondo de pensiones, América Latina. Capitalization, Administration Costs, Pension Funds, Latin America

    Obstructive Sleep Apnea Syndrome (OSAS). Review of the literature

    Get PDF
    Obstructive sleep apnea and hypopnea syndrome is characterized by repeated airway collapse during sleep. The literature describes multiple causes of the disease. The main cause is a reduction of the expansion forces of the pharyngeal dilator muscles, as in situations of genioglossal muscle dysfunction, and discoordination between the inspiratory activity of the muscle and respiratory effort, which play an important role in progression of the disease. Other described causes are soft tissue disorders, such as macroglossia or tonsillar hypertrophy, and skeletal structural alterations such as micrognathia and retrognathia. The syndrome is also more frequent in obese people, where the accumulation of fat in the neck region produces narrowing of th pharyngeal airway, thereby diminishing the passage of air. This review focuses on the pathogenesis, epidemiology, main features and diagnosis of the disease, and on its main forms of treatment

    Obstructive sleep apnea syndrome (OSAS): review of the literature

    Get PDF
    Obstructive sleep apnea and hypopnea syndrome is characterized by repeated airway collapse during sleep. The literature describes multiple causes of the disease. The main cause is a reduction of the expansion forces of the pharyngeal dilator muscles, as in situations of genioglossal muscle dysfunction, and discoordination between the inspiratory activity of the muscle and respiratory effort, which play an important role in progression of the disease. Other described causes are soft tissue disorders, such as macroglossia or tonsillar hypertrophy, and skeletal structural alterations such as micrognathia and retrognathia. The syndrome is also more frequent in obese people, where the accumulation of fat in the neck region produces narrowing of the pharyngeal airway, thereby diminishing the passage of air. This review focuses on the pathogenesis, epidemiology, main features and diagnosis of the disease, and on its main forms of treatment

    Effect of temperature on the orthodontic clinical applications of niti closed-coil springs

    Get PDF
    NiTi spring coils were used to obtain large deformation under a constant force. The device consists on a NiTi coil spring, superelastic at body temperature, in order to have a stress plateau during the austenitic retransformation during the unloading. The temperature variations induced changes in the spring force. Objectives: The aim of this study is to investigate the effect of the temperature variations in the spring forces and corrosion behaviour simulating the ingestion hot/cold drinks and food. Study D esign: The springs were subjected to a tensile force using universal testing machine MTS-Adamel (100 N load cell). All tests were performed in artificial saliva maintained at different temperatures. The corrosion tests were performed according to the ISO-standard 10993-15:2000. Results: The increase in temperature of 18 o C induced an increase in the spring force of 30%. However, when the temperature returns to 37 o C the distraction force recovers near the initial level. After cooling down the spring to 15 o C, the force decreased by 46%. This investigation show as the temperature increase, the corrosion potential shifts towards negative values and the corrosion density is rising. Conclusions: The changes of the temperatures do not modify the superelastic behaviour of the NiTi closed-coil springs. The corrosion potential of NiTi in artificial saliva is decreasing by the rise of the temperatures

    DESIGN AND INTEGRATION OF A HUMAN-ROBOT PHYSICAL INTERACTION PLATFORM WITH PURPOSES OF MEDICAL DIAGNOSIS AND REHABILITATION OF UPPER LIMB

    Get PDF
    In this paper a human-robot physical interaction system with purposes of diagnosis and rehabilitation of upper limb is proposed.Anunderactuatedhaptic device with six degrees of freedom is used, with low inertia and low joint friction.Adaptive control technique is used for passive haptic guidance and active exploration, in order to compensate the dynamic uncertainty of the human operator in the loop.To validate the experimental platform, a procedure is established with three steps: i) knowledge of the haptic interface (interaction with the kinematic virtual environment), ii) navigation in a virtual pipe with changes in the geometric characteristics (verification of position, velocity, collisions and runtime), and iii) haptic guidance in a structured path based on a clinical protocol (study of convergence and energy).Environmental conditions such as temperature, humidity, lighting and noise are characterizedwith purposes to define experimental conditions.In this work, we assess based on the NASA-TLX protocol,the workload perception of simple temporal-spatial tasks

    Lower incisor position in different malocclusions and facial patter

    Get PDF
    Introduction: The position of lower incisor has been of considerable concern when planning an orthodontic treatment, having been recognized as one of diagnostic keys, Very important in the development of malocclusion and facial pattern. Objectives: In this study we claim to determine the importance of the position and inclination of lower incisor in the different malocclusions and facial patterns, and to base which of the cephalometric measurement parameters are the mostreliable. Material and Methods: Ninety lateral radiographies were taken, and they were classified by skeletal malocclusion and facial pattern.These teleradiographies have been performed cephalometric analysis, which includelower incisor position belong the following analysis: Ricketts, Riolo, Tweed, McHorris, Jarabak-MSE and Holdaway. Study Design: Cross-sectional study where we perform statistical analysis Anova test, Pearson correlations and Bonferroni analysis. Results: The analyzed measurements present a statistically significant differentiation in lower incisor inclination respect to the anterior cranial base, McHorris angle, angulation of lower incisor respect to occlusal plane and mandibular plane. Conclusions: There are statistically significant differentiation in lower incisor position and inclination respect the malocclusion and individual facial pattern

    DESIGN AND INTEGRATION OF A HUMAN-ROBOT PHYSICAL INTERACTION PLATFORM WITH PURPOSES OF MEDICAL DIAGNOSIS AND REHABILITATION OF UPPER LIMB

    Get PDF
    In this paper a human-robot physical interaction system with purposes of diagnosis and rehabilitation of upper limb is proposed.Anunderactuatedhaptic device with six degrees of freedom is used, with low inertia and low joint friction.Adaptive control technique is used for passive haptic guidance and active exploration, in order to compensate the dynamic uncertainty of the human operator in the loop.To validate the experimental platform, a procedure is established with three steps: i) knowledge of the haptic interface (interaction with the kinematic virtual environment), ii) navigation in a virtual pipe with changes in the geometric characteristics (verification of position, velocity, collisions and runtime), and iii) haptic guidance in a structured path based on a clinical protocol (study of convergence and energy).Environmental conditions such as temperature, humidity, lighting and noise are characterizedwith purposes to define experimental conditions.In this work, we assess based on the NASA-TLX protocol,the workload perception of simple temporal-spatial tasks

    Edades radiométricas de los edificios miocenos de Fuerteventura (Islas Canarias).

    Get PDF
    Se han realizado once nuevas dataciones K-Ar de las coladas básicas (basaltos, nefelinitas) y sálicas (traquitas) de los tres edificios principales subaéreos (Tetir o Norte, Gran Tarajal o Central y Jandía o Sur) que constituyen la Fase miocena de la isla. Se precisa algo más la cronoestratigrafía relativa entre ellos, así como la correspondiente a los tramos que los integran

    True vertical validation in facial orthognathic surgery planning

    Get PDF
    Objectives: To validate the effectiveness of the original standards of True Vertical (TV) Subnasal Line in orthognatic surgery planning. The present study evaluates the changes occurring in patients with skeletal Class II alterations programmed for orthognathic surgery with a view to improving their facial profile. Study desing: We showed a series of black profiles (composed by a first control group of subjects with normal occlusion, and another two additional groups comprised patients before -Group 2- and after orthognatic surgical correction of Class II malocclusion -Group 3-) for three groups of observers (orthodontists, surgeons and laypeople). The facial images became black silhouettes in order to determine a series of parameters (including aesthetic assessment) by means of the observers. Their observation were assessed using a 5-point Likert scale. Results: The sample was composed of 52 profile's subjects who were tested for a total of 72 observers. Aesthetic assessment yielded mean scores of 2.57, 1.67 and 2.46 for groups 1, 2 and 3, respectively. There was a statistically significant difference (p<0.001) between group 1 versus group 2. There were no significant differences in terms of observer assessment of aesthetics, with the exception of a wider perception range among the orthodontists. Regarding the studied profile measures, significant differences were recorded for point B' and Pg' (p<0.02) between groups 2 and 3 (i.e., pre- versus post-surgery). Conclusions: The results of our study suggest the subnasale vertical and sagittal measures of the lower third of the face are decisive in facial aesthetics, and therefore also for the planning of orthognathic surgery. Consequently, these aesthetic parameters can be used as an objective tool for the planning of orthodontic treatment

    Wilson maxillary curve analyzed by cbct a study on normocclusion and malocclusion individuals

    Get PDF
    The anatomy of dental compensation curve in the frontal plane described by George H. Wilson is one of the occlusal determinants of orthodontic treatment. However, there is few published comparing malocclusion and normocclusion individuals. Objectives: The aim of this study is to compare the curve of Wilson at first and second maxillary molars, normocclusion pattern and malocclusion pattern, with and without bilateral posterior crossbite, using angular references in CBCT studies. Material and Methods: We analyzed 10 cases of malocclusion with bilateral posterior crossbite, 10 cases of malocclusion without bilateral posterior crossbite and 10 cases with non orthodontic normocclusion (patients who underwent cone beam study for other reasons than orthodontic). All of them were adults, more than 19 years. Angular variables from left and right axis (line connecting the occlusal and furcation groove) of first and second molars towards a perpendicular to the frontal palate were measured. There was carried out an Anova test, Bonferroni analysis and Levene's statistics. Results: The descriptive analysis of the results shows an average values of total maxillary curve of Wilson for first molars (sum of left and right angle) of 8.1° for normocclusion group, 0.4° for the malocclusion pattern with bilateral posterior crossbite and 16.9° for the malocclusion pattern without this alteration. The mean differences was statistical significant (P<0,042) between between malocclusion pattern groups with and without crossbite . Conclusion: The curve of Wilson, measured at maxillary first molars in patients with bilateral posterior crossbite is more concave than the other groups, suggesting no dentoalveolar compensations
    corecore