551 research outputs found

    Adaptive control of a solar furnace for material testing

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    IFAC Adaptive Systems in Control and Signal Processing. Glasgow. Scotland. UK. 26/08/1998This paper presents an adaptive control system for controlling the temperature of a solar furnace, which is a high solar concentrating facility made up of heliostats tracking the sun and reflecting solar radiation onto a static parabolic concentrating system at the focal spot of which a high percentage of the solar energy collected by the collector system is concentrated in a small area. A large attenuator (shutter) placed between the collector system and the concentrator serves to control the amount of solar energy used for heating the samples placed at the focal spot. The paper shows the results obtained in the application of adaptive PI controllers to a solar furnace, incorporating feedforward action, anti-windup and slew rate constraint handling mechanisms

    Síndrome del tunel carpiano

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    La compresión del nervio mediano o síndrome del túnel carpiano es la neuropatía por atrapamiento más frecuente. Presenta unos síntomas -y en ocasiones unos signos- característicos que es preciso recordar. La etiología es multifactorial –anatómica, sistémica, ocupacional laboral, etc.-. El diagnóstico se basa en la anamnesis, exploración física y confirmación electromiográfica. Su cronicidad conlleva a una reactivación de la clínica y menoscabo funcional. La amplia fisiopatología, frecuencia y tratamientos conservadores entre ellos la inmovilización, el rehabilitador –programa de fisioterapia de deslizamiento nervioso-, la infiltración corticoidea i.e., son resolutivos. La cirugía se reserva como terapia liberadora cada vez menos invasiva en sus diversas técnicas. Presentamos una técnica de miniincisión, de corta cicatriz, con rápida recuperación clínica y laboral, baja morbilidad y riesgos limitados, en comparación con la técnica clásica abierta y la endoscópica.Carpal tunnel syndrome is the most common compressive neuropathy of the upper extremity. As a result of median nerve compression, the patient reports pain, weakness, and paresthesias in the hand and fingers. The etiology of this condition is multifactorial: anatomic, systemic, and occupational factors have all been implicated. The diagnosis is based on the patient history, physical examination and is confirmed by electrodiagnostic testing. Treatment methods range from observation and splinting; workplace task modification and wrist splints can reduce or defer referral to hospital for surgical decompression. Nerve and tendon gliding exercises may also be of benefit. The short-incision we present, also called mini-open, may allow for quicker recovery time, minimal scar, no tenderness, low morbidity, while avoiding some of the complications of endoscopy and than with the open approach, found in the few article

    Estudio de la anteversión femoral

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    Se estudian los valores angulares de la anteversión femoral en 30 fémures humanos secos normales, del lado izquierdo y pertenecientes a individuos adultos. Los valores angulares de la muestra son sometidos a estudio estadístico dando una fiabilidad de la media para p = 0,01 . Se revisa la bibliografía de otras mediciones realizadas en hueso seco y se comparan con los valores obtenidos en este trabajo. Los valores obtenidos contribuirán a un mejor conocimiento del ángulo de anteversión femoral y consecuentemente a la aplicación clínica del mismo

    Application of Global Positioning System and questionnaires data for the study of driver behavior on two-lane rural roads

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    This paper is a preprint of a paper accepted by IET Intelligent Transport Systems and is subject to Institution of Engineering and Technology Copyright. When the final version is published, the copy of record will be available at IET Digital LibraryMethodologies based on naturalistic observation provide the most accurate data for studying drivers' behaviour. This study presents a new methodology to obtain naturalistic data related to drivers' behaviour in a road segment. It is based on the combination of using global positioning system data and drivers' questionnaires. The continuous speed profiles along a road segment and the characteristics of drivers, of their trips and the type of their vehicles can be obtained for a great amount of drivers. It has already been successfully used for several studies, such as the development of models to estimate operating speed profile in two-lane rural road segments; or the characterisation of driving styles. These operating speed models have been the key for the development of a new geometric design consistency model, allowing an easier road safety evaluation. Besides, knowledge on the human factors that influence speed choice may be useful for road safety media campaigns and education programs designers, and also for the improvement of intelligent driver assistance systems.The authors thank 'Centre for Studies and Experimentation of Public Works (CEDEX)' of the 'Spanish Ministry of Public Works' that partially subsidizes the research. We also wish to thank to the 'General Directorate of Public Works, Urban Projects and Housing' of the 'Infrastructure, Territory and Environment Department' of the 'Valencian Government', to the 'Valencian Provincial Council' and to the 'General Directorate of Traffic' of the 'Ministry of the Interior' for their cooperation in field data gathering.Pérez Zuriaga, AM.; Camacho Torregrosa, FJ.; Campoy Ungria, JM.; García García, A. (2013). Application of Global Positioning System and questionnaires data for the study of driver behavior on two-lane rural roads. IET Intelligent Transport Systems. 7(2):182-189. doi:10.1049/iet-its.2012.0151S18218972Fourie, M., Walton, D., & Thomas, J. A. (2011). Naturalistic observation of drivers’ hands, speed and headway. Transportation Research Part F: Traffic Psychology and Behaviour, 14(5), 413-421. doi:10.1016/j.trf.2011.04.009Gibreel, G. M., Easa, S. M., & El-Dimeery, I. A. (2001). Prediction of Operating Speed on Three-Dimensional Highway Alignments. Journal of Transportation Engineering, 127(1), 21-30. doi:10.1061/(asce)0733-947x(2001)127:1(21)Fitzpatrick, K., & Collins, J. M. (2000). Speed-Profile Model for Two-Lane Rural Highways. Transportation Research Record: Journal of the Transportation Research Board, 1737(1), 42-49. doi:10.3141/1737-06Bella, F. (2008). Driving simulator for speed research on two-lane rural roads. Accident Analysis & Prevention, 40(3), 1078-1087. doi:10.1016/j.aap.2007.10.015Van Nes, N., Houtenbos, M., & Van Schagen, I. (2008). Improving speed behaviour: the potential of in-car speed assistance and speed limit credibility. IET Intelligent Transport Systems, 2(4), 323. doi:10.1049/iet-its:20080036Warner, H. W., & Åberg, L. (2006). Drivers’ decision to speed: A study inspired by the theory of planned behavior. Transportation Research Part F: Traffic Psychology and Behaviour, 9(6), 427-433. doi:10.1016/j.trf.2006.03.004Goldenbeld, C., & van Schagen, I. (2007). The credibility of speed limits on 80km/h rural roads: The effects of road and person(ality) characteristics. Accident Analysis & Prevention, 39(6), 1121-1130. doi:10.1016/j.aap.2007.02.012Zuriaga, A. M. P., García, A. G., Torregrosa, F. J. C., & D’Attoma, P. (2010). Modeling Operating Speed and Deceleration on Two-Lane Rural Roads with Global Positioning System Data. Transportation Research Record: Journal of the Transportation Research Board, 2171(1), 11-20. doi:10.3141/2171-02Ottesen, J. L., & Krammes, R. A. (2000). Speed-Profile Model for a Design-Consistency Evaluation Procedure in the United States. Transportation Research Record: Journal of the Transportation Research Board, 1701(1), 76-85. doi:10.3141/1701-10Park, P. Y., Miranda-Moreno, L. F., & Saccomanno, F. F. (2010). Estimation of speed differentials on rural highways using hierarchical linear regression models. Canadian Journal of Civil Engineering, 37(4), 624-637. doi:10.1139/l10-002Wasielewski, P. (1984). Speed as a measure of driver risk: Observed speeds versus driver and vehicle characteristics. Accident Analysis & Prevention, 16(2), 89-103. doi:10.1016/0001-4575(84)90034-4Williams, A. F., Kyrychenko, S. Y., & Retting, R. A. (2006). Characteristics of speeders. Journal of Safety Research, 37(3), 227-232. doi:10.1016/j.jsr.2006.04.001Lajunen, T., Karola, J., & Summala, H. (1997). Speed and Acceleration as Measures of Driving Style in Young Male Drivers. Perceptual and Motor Skills, 85(1), 3-16. doi:10.2466/pms.1997.85.1.3Af Wåhlberg, A. E. (2006). Speed choice versus celeration behavior as traffic accident predictor. Journal of Safety Research, 37(1), 43-51. doi:10.1016/j.jsr.2005.10.01

    Laboratory diagnosis of severe hypertriglyceridaemia. Cases from the dyslipidaemia regristy of the spanish atherosclerosis society

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    Background and Aims Severe hypertriglyceridaemia (sHTG) increases the risk of cardiovascular disease and acute pancreatitis episodes. Patients with sHTG fit mainly into two clinical entities: Familial or Multifactorial Chylomicronemia Syndromes (FCS and MCS, respectively). FCS and MCS exhibit clinical differences but also separate genetic and biochemical characteristics that can be assessed in the laboratory. The aim of this work has been to implement a laboratory workflow to help diagnose sHTG patients with either FCS or MCS. Methods Patients with two fasting triglycerides >1000mg/dL determinations were sequenced with a capture probe panel of 24 triglycerides-related genes using massive parallel sequencing (n=200). Two-step sequential ultracentrifugation was performed (n= 159) to diagnose Type I hyperlipoproteinemia (HLP I) and post heparin lipoprotein lipase activity was measured to discard or confirm its deficiency (n=60). Results Most patients had MCS as they: (i) did not exhibit HLPI and/or (ii) their genetic profile was not compatible with FCS and (iii) were not deficient in LPL activity. FCS cases were identified as they had: (i) HLPI, and/or (ii) biallelic pathogenic variants in LPL (n=5), GPIHBP1 (n=3), or LMF1 (n=2) genes and/or (iii) LPL activity deficiency. We identified 4 FCS patients with HLPI, biallelic pathogenic variants in APOA5 but a rescued LPL activity. An additional study of Apo-AV functionality was designed to confirm the FCS diagnosis in these cases. Conclusions Laboratory studies, in patients with severe hypertriglyceridaemia, provide with information of clinical utility to distinguish between Familial and Multifactorial Chylomicronemia Syndromes.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Generalized Parton Distributions from Hadronic Observables: Non-Zero Skewness

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    We propose a physically motivated parametrization for the unpolarized generalized parton distributions, H and E, valid at both zero and non-zero values of the skewness variable, \zeta. Our approach follows a previous detailed study of the \zeta=0 case where H and E were determined using constraints from simultaneous fits of the experimental data on both the nucleon elastic form factors and the deep inelastic structure functions in the non singlet sector. Additional constraints at \zeta \neq 0 are provided by lattice calculations of the higher moments of generalized parton distributions. We illustrate a method for extracting generalized parton distributions from lattice moments based on a reconstruction using sets of orthogonal polynomials. The inclusion in our fit of data on Deeply Virtual Compton Scattering is also discussed. Our method provides a step towards a model independent extraction of generalized distributions from the data. It also provides an alternative to double distributions based phenomenological models in that we are able to satisfy the polynomiality condition by construction, using a combination of experimental data and lattice, without resorting to any specific mathematical construct.Comment: 29 pages, 8 figures; added references, changed text in several place

    Sum rules and dualities for generalized parton distributions: is there a holographic principle?

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    To leading order approximation, the physical content of generalized parton distributions (GPDs) that is accessible in deep virtual electroproduction of photons or mesons is contained in their value on the cross-over trajectory. This trajectory separates the t-channel and s-channel dominated GPD regions. The underlying Lorentz covariance implies correspondence between these two regions through their relation to GPDs on the cross-over trajectory. This point of view leads to a family of GPD sum rules which are a quark analogue of finite energy sum rules and it guides us to a new phenomenological GPD concept. As an example, we discuss the constraints from the JLab/Hall A data on the dominant u-quark GPD H. The question arises whether GPDs are governed by some kind of holographic principle.Comment: 45 pages, 4 figures, Sect. 2 reorganized for clarity. Typos in Eq. (20) corrected. 4 new refs. Matches published versio

    Controlled clinical trial comparing the effectiveness of a mindfulness and self-compassion 4-session programme versus an 8-session programme to reduce work stress and burnout in family and community medicine physicians and nurses: MINDUUDD study protocol

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    Background: Health personnel are susceptible to high levels of work stress and burnout due to the psychological and emotional demands of their work, as well as to other aspects related to the organisation of that work. This paper describes the rationale and design of the MINDUUDD study, the aim of which is to evaluate the effectiveness of a mindfulness and self-compassion 4-session programme versus the standard 8-session programme to reduce work stress and burnout in Family and Community Medicine and Nursing tutors and residents. Methods: The MINDUDD study is a multicentre cluster randomised controlled trial with three parallel arms. Six Teaching Units will be randomised to one of the three study groups: 1) Experimental Group-8 (EG8); 2) Experimental Group-4 (EG4) Control group (CG). At least 132 subjects will participate (66 tutors/66 residents), 44 in the EG8, 44 in the EG4, and 44 in the CG. Interventions will be based on the Mindfulness-Based Stress Reduction (MBSR) program, including some self-compassion practices of the Mindful Self-Compassion (MSC) programme. The EG8 intervention will be implemented during 8 weekly face-to-face sessions of 2.5 h each, while the EG4 intervention will consist of 4 sessions of 2.5 h each. The participants will have to practice at home for 30 min/day in the EG8 and 15 min/day in the EG4. The Five Facet Mindfulness Questionnaire (FFMQ), Self-Compassion Scale (SCS), Perceived Stress Questionnaire (PSQ), Maslach Burnout Inventory (MBI), Jefferson Scale of Physician Empathy (JSPE), and Goldberg Anxiety-Depression Scale (GADS) will be administered. Measurements will be taken at baseline, at the end of the programs, and at three months after completion. The effect of the interventions will be evaluated by bivariate and multivariate analyses (Multiple Linear Regression). Discussion: If the abbreviated mindfulness programme is at least as effective as the standard program, its incorporation into the curriculum and training plans will be easier and more appropriate. It will also be more easily applied and accepted by primary care professionals because of the reduced resources and means required for its implementation, and it may also extend beyond care settings to academic and teaching environments as well
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