262 research outputs found

    Filament Advance Detection Sensor for Fused Deposition Modelling 3D Printers

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    The main purpose of this paper is to present a system to detect extrusion failures in fused deposition modelling (FDM) 3D printers by sensing that the filament is moving forward properly. After several years using these kind of machines, authors detected that there is not any system to detect the main problem in FDM machines. Authors thought in different sensors and used the weighted objectives method, one of the most common evaluation methods, for comparing design concepts based on an overall value per design concept. Taking into account the obtained scores of each specification, the best choice for this work is the optical encoder. Once the sensor is chosen, it is necessary to design de part where it will be installed without interfering with the normal function of the machine. To do it, photogrammetry scanning methodology was employed. The developed device perfectly detects the advance of the filament without affecting the normal operation of the machine. Also, it is achieved the primary objective of the system, avoiding loss of material, energy, and mechanical wear, keeping the premise of making a low-cost product that does not significantly increase the cost of the machine. This development has made it possible to use the printer with remains of coil filaments, which were not spent because they were not sufficient to complete an impression. Also, printing models in two colours with only one extruder has been enabled by this development

    Dispositivo de fijación, cierre y acoplamiento para catéter de perfusión intravenosa

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    Introducción: los medios de fijación a la piel de un catéter venoso periférico, de un catéter venoso central o de un catéter arterial central presentan los siguientes graves inconvenientes: ser la sede de infecciones a nivel del lugar de la punción, provocar una saturación de la zona anatómica, la cual resulta muy difícil de soportar e incómodo para el paciente portador, y suponer un riesgo para el personal de enfermería cuando se usan hilos de sutura para fijar el soporte del catéter. Objetivo: por lo anteriormente expuesto, se ha detectado la necesidad de diseñar un dispositivo que reduzca la complejidad y aparatosidad de los sistemas conocidos y empleados en la actualidad, favoreciendo la asepsia y la movilidad del paciente. Método: el desarrollo presentado en este artículo se refiere a un sistema mecánico de fijación, cierre y acoplamiento para catéter de perfusión intravenosa. El sistema dispone de una pieza circular de pequeño espesor con al menos dos orificios para su fijación subcutánea, centralmente de uno o más conductos para acoplar lúmenes, y de una parte cilíndrica hueca que sobresale a uno de los lados, exteriormente roscada e interiormente lisa con un tetón de posición. Para uso domiciliario se dispone de un tapón de estanqueidad con uno o más tubos de pequeño diámetro que se acoplan en los orificios para lúmenes, una ranura de posición, un tirador y un tapón roscado ciego para el cierre hermético con la parte roscada. Para uso hospitalario se dispone de un tapón intermedio con una o más entradas para lúmenes, así como de un tapón roscado hueco que permite su acoplamiento hermético con la parte roscada. Resultados: el desarrollo descrito en este artículo va a ser utilizado en dos ambientes: ambiente domiciliario y ambiente hospitalario. Además, reduce el riesgo de infección y saturación de la zona anatómica de los pacientes en los que se realiza la punción cutánea en la que se fijan catéteres venosos periféricos, catéteres venosos centrales o catéteres arteriales centralesIntroduction: skin fixing devices in peripheral, central or arterial catheters have several important drawbacks: site infection, stacking of material in the anatomical area which is very annoying for the patient and medical staff risk when fixating stitches are used. Objective: to develop a fixing device that simplifies presently used systems, favoring asepsis and motility. Methods: the device herein described is composed by a mechanical fixation, a closing system and coupling for intravenous catheters. The system has a thin circular piece with at least two holes for subcutaneous fixation, one or several conducts for lumina and a hollow cylindrical part in one side, screwed exteriorly and flat inside, with an oriented protuberance. A watertight plug with one or several thin tubes that adapt to the lumina, a positional slot, a handle and a solid screwed tap for perfect closure are available for at home use. An intermediate plug with one or several lumina and a screwed hollow plug are provided for in hospital use. Results: the above described device is intended to be used in two settings: in hospital and at home. It is supposed to reduce the risk of infection and stacking of the anatomical site where cutaneo us puncture with fixation of peripheral, central or arterial catheters is performe

    Influencia del riego deficitario controlado precosecha sobre la calidad de la cereza ´Prime Giant`

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    El uso de redes de sensores para el manejo del riego deficitario controlado (RDC) en cerezo puede incidir en la mejora de la productividad del agua, calidad de la fruta y en su comportamiento poscosecha, al permitir el conocimiento y control del estado hídrico del suelo y árbol en todo momento. En el primer año de ensayo, el riego deficitario aplicado en precosecha para satisfacer el 85% de las necesidades máximas del cultivo (ETcg) permitió un ahorro de agua del 17% (380 m3 ha-1) respecto al tratamiento control, que se regó al 110% de la ETcg. Este déficit hídrico ligero no afectó a la producción (16,13 t ha-1) e incluso mejoró la calidad del fruto. Así, en el momento de la cosecha (t0) los frutos bajo déficit ligero presentaron matices más rojos y mayor acidez que los de riego completo. Esta mayor acidez no afectó al índice de madurez debido a la compensación por sólidos solubles totales (SST). El carácter de mayor acidez perduró tras 30 días de conservación en frio (t1) y 5 días de simulación de las condiciones de comercialización (t2). Igualmente, los frutos bajo déficit hídrico presentaron una tendencia a menores pérdidas de peso por deshidratación a finales de los periodos de conservación en frio y de simulación de la comercialización.Ministerio de Economía y Competitividad AGL2013-49047-C2-1

    Skin picking treatment with the Rothbaum cognitive behavioral therapy protocol : a randomized clinical trial

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    Introduction: Although behavioral therapies can effectively treat skin picking disorder (SPD), there is no standardized treatment for improving SPD and its comorbidities and there is no group intervention option. This trial aimed to adapt the Rothbaum trichotillomania protocol to SPD (Study 1) and test its efficacy for treating SPD and comorbidities in individual and group formats (Study 2). Methods: The adapted protocol was applied to 16 SPD patients, who were allocated to group or individual treatment (Study 1). Afterwards, 54 patients were randomly allocated to treatment in an individual (n=27) or group format (n=27) (Study 2). In both studies, assessments of SPD severity, anxiety, depression, clinical status and skin lesion severity were performed at baseline and the endpoint. Results: The adapted protocol was feasible in both treatment modalities (Study 1) and led to high SPD remission rates (individual 63%; group 52%), with no significant difference between intervention types (p = 0.4) (Study 2). SPD, anxiety, and depression symptoms and objective patient lesion measures improved after treatment. There was large effect size for SPD symptom improvement in both treatment types (Cohen’s d: group = 0.88; individual = 1.15) (Study 2). Conclusion: The adapted Rothbaum protocol was effective for SPD remission, comorbidities, and skin lesions, both in individual and group formats

    On the Lebesgue measure of Li-Yorke pairs for interval maps

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    We investigate the prevalence of Li-Yorke pairs for C2C^2 and C3C^3 multimodal maps ff with non-flat critical points. We show that every measurable scrambled set has zero Lebesgue measure and that all strongly wandering sets have zero Lebesgue measure, as does the set of pairs of asymptotic (but not asymptotically periodic) points. If ff is topologically mixing and has no Cantor attractor, then typical (w.r.t. two-dimensional Lebesgue measure) pairs are Li-Yorke; if additionally ff admits an absolutely continuous invariant probability measure (acip), then typical pairs have a dense orbit for f×ff \times f. These results make use of so-called nice neighborhoods of the critical set of general multimodal maps, and hence uniformly expanding Markov induced maps, the existence of either is proved in this paper as well. For the setting where ff has a Cantor attractor, we present a trichotomy explaining when the set of Li-Yorke pairs and distal pairs have positive two-dimensional Lebesgue measure.Comment: 41 pages, 3 figure

    Diffusion of e-health innovations in 'post-conflict' settings: a qualitative study on the personal experiences of health workers.

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    BACKGROUND: Technological innovations have the potential to strengthen human resources for health and improve access and quality of care in challenging 'post-conflict' contexts. However, analyses on the adoption of technology for health (that is, 'e-health') and whether and how e-health can strengthen a health workforce in these settings have been limited so far. This study explores the personal experiences of health workers using e-health innovations in selected post-conflict situations. METHODS: This study had a cross-sectional qualitative design. Telephone interviews were conducted with 12 health workers, from a variety of cadres and stages in their careers, from four post-conflict settings (Liberia, West Bank and Gaza, Sierra Leone and Somaliland) in 2012. Everett Roger's diffusion of innovation-decision model (that is, knowledge, persuasion, decision, implementation, contemplation) guided the thematic analysis. RESULTS: All health workers interviewed held positive perceptions of e-health, related to their beliefs that e-health can help them to access information and communicate with other health workers. However, understanding of the scope of e-health was generally limited, and often based on innovations that health workers have been introduced through by their international partners. Health workers reported a range of engagement with e-health innovations, mostly for communication (for example, email) and educational purposes (for example, online learning platforms). Poor, unreliable and unaffordable Internet was a commonly mentioned barrier to e-health use. Scaling-up existing e-health partnerships and innovations were suggested starting points to increase e-health innovation dissemination. CONCLUSIONS: Results from this study showed ICT based e-health innovations can relieve information and communication needs of health workers in post-conflict settings. However, more efforts and investments, preferably driven by healthcare workers within the post-conflict context, are needed to make e-health more widespread and sustainable. Increased awareness is necessary among health professionals, even among current e-health users, and physical and financial access barriers need to be addressed. Future e-health initiatives are likely to increase their impact if based on perceived health information needs of intended users
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