476 research outputs found

    Methodology for Part Visualization Problem Solving - the Importance of the Process

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    Part visualization is a fundamental skill in engineering. It comprises the reading, interpretation and creation of industrial technical drawings, understanding the different views (multi-view) of an object/piece represented in any technical drawing. The ability to mentally visualize and manipulate objects and situations is an essential need in many jobs and careers. It is estimated that at least 84 majors consider visualization a fundamental need, and in technical jobs, many of them related to the different types of engineering, the ability to visualize has a crucial importance. Educators have often pointed out the difficulties of most students in graphic courses when trying to visualize an object using multi-view drawings. This is mainly due to the inexistence of a systematic process to analyze complex forms. A thorough review of the literature in technical drawing textbooks has not been successful in finding a clear, concise, and properly developed method of solving visualization problems by means of procedural contents. In collaboration with several experts and for the first time, a problem solving model for visualization has been designed and developed for all kind of industrial objects (Methodology for Part Visualization Problem Solving) within a constructivist didactic framework. This Problem Solving model is the key to all technical knowledge and is an application of the scientific method. In order to solve visualization problems in any kind of industrial object, comprehension indicators have been defined and a Teaching Unit has been developed with the help of dynamic images (power point and CAD files) as well as physical models. They may be applied by drawing up a programme of specific tasks which takes into account the theoretical contents and procedures involved in part visualization as well as the students\\u27 main difficulties and deficiencies when faced with this kind of problem. This teaching strategy has been applied over the last two years in the first year of Industrial Engineering at the Department of Engineering in Bilbao at the University of the Basque Country with good results

    Deterministic Generation of Large Fock States

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    We present a protocol to deterministically prepare the electromagnetic field in a large photon number state. The field starts in a coherent state and, through resonant interaction with one or few two-level systems, it evolves into a coherently displaced Fock state, without any post-selection. We show the feasibility of the scheme under realistic parameters. The presented method opens a door to reach Fock states with n∼100n\sim100 and optimal fidelities above 7070%, blurring the line between macroscopic and quantum states of the field

    Inflection, Canards and Folded Singularities in Excitable Systems: Application to a 3D FitzHugh–Nagumo Model

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    Specific kinds of physical and biological systems exhibit complex Mixed-Mode Oscillations mediated by folded-singularity canards in the context of slow-fast models. The present manuscript revisits these systems, specifically by analysing the dynamics near a folded singularity from the viewpoint of inflection sets of the flow. Originally, the inflection set method was developed for planar systems [Brøns and Bar-Eli in Proc R Soc A 445(1924):305–322, 1994; Okuda in Prog Theor Phys 68(6):1827–1840, 1982; Peng et al. in Philos Trans R Soc A 337(1646):275–289, 1991] and then extended to N-dimensional systems [Ginoux et al. in Int J Bifurc Chaos 18(11):3409–3430, 2008], although not tailored to specific dynamics (e.g. folded singularities). In our previous study, we identified components of the inflection sets that classify several canard-type behaviours in 2D systems [Desroches et al. in J Math Biol 67(4):989– 1017, 2013]. Herein, we first survey the planar approach and show how to adapt it for 3D systems with an isolated folded singularity by considering a suitable reduction of such 3D systems to planar non-autonomous slow-fast systems. This leads us to the computation of parametrized families of inflection sets of one component of that planar (non-autonomous) system, in the vicinity of a folded node or of a folded saddle. We then show that a novel component of the inflection set emerges, which approximates and follows the axis of rotation of canards associated to folded-node and folded-saddle singularities. Finally, we show that a similar inflection-set component occurs in the vicinity of a delayed Hopf bifurcation, a scenario that can arise at the transition between folded node and folded saddle. These results are obtained in the context of a canonical model for folded-singularity canards and subsequently we show it is also applicable to complex slow-fast models. Specifically, we focus the application towards the self-coupled 3D FitzHugh–Nagumo model, but the method is generically applicable to higher-dimensional models with isolated folded singularities, for instance in conductance-based models and other physical-chemical systems.Ikerbasque (The Basque Foundation for Science

    High Resolution Zero-Shot Domain Adaptation of Synthetically Rendered Face Images

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    Generating photorealistic images of human faces at scale remains a prohibitively difficult task using computer graphics approaches. This is because these require the simulation of light to be photorealistic, which in turn requires physically accurate modelling of geometry, materials, and light sources, for both the head and the surrounding scene. Non-photorealistic renders however are increasingly easy to produce. In contrast to computer graphics approaches, generative models learned from more readily available 2D image data have been shown to produce samples of human faces that are hard to distinguish from real data. The process of learning usually corresponds to a loss of control over the shape and appearance of the generated images. For instance, even simple disentangling tasks such as modifying the hair independently of the face, which is trivial to accomplish in a computer graphics approach, remains an open research question. In this work, we propose an algorithm that matches a non-photorealistic, synthetically generated image to a latent vector of a pretrained StyleGAN2 model which, in turn, maps the vector to a photorealistic image of a person of the same pose, expression, hair, and lighting. In contrast to most previous work, we require no synthetic training data. To the best of our knowledge, this is the first algorithm of its kind to work at a resolution of 1K and represents a significant leap forward in visual realism

    Immobilisation of electrochemically active bacteria on screen-printed electrodes for rapid in situ toxicity biosensing

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    Microbial biosensors can be an excellent alternative to classical methods for toxicity monitoring, which are time-consuming and not sensitive enough. However, bacteria typically connect to electrodes through biofllm formation, leading to problems due to lack of uniformity or long device production times. A suitable immobilisation technique can overcome these challenges. Still, they may respond more slowly than biofllm-based electrodes because bacteria gradually adapt to electron transfer during biofllm formation. In this study, we propose a controlled and reproducible way to fabricate bacteria-modified electrodes. The method consists of an immobilisation step using a cellulose matrix, followed by an electrode polarization in the presence of ferricyanide and glucose. Our process is short, reproducible and led us to obtain ready-to-use electrodes featuring a high-current response. An excellent shelf-life of the immobilised electrochemically active bacteria was demonstrated for up to one year. After an initial 50% activity loss in the first month, no further declines have been observed over the following 11 months. We implemented our bacteria-modified electrodes to fabricate a lateral flow platform for toxicity monitoring using formaldehyde (3%). Its addition led to a 59% current decrease approximately 20 min after the toxic input. The methods presented here offer the ability to develop a high sensitivity, easy to produce, and long shelf life bacteria-based toxicity detectors. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of Chinese Society for Environmental Sciences, Harbin Institute of Technology, Chinese Research Academy of Environmental Sciences

    Prescripción inducida en atención primaria de la Comarca Bilbao

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    ObjetivosPrincipales: conocer la proporción de prescripción inducida (PI) en Comarca Bilbao y su procedencia, la proporción de gasto correspondiente a la PI, la proporción de PI en los principales grupos terapéuticos, la actitud del médico de atención primaria ante la prescripción solicitada y su influencia en el gasto, la proporción de desacuerdo con dicha prescripción y los motivos de desacuerdo, y la proporción con informe del especialista. Secundarios: conocer la proporción de PI en los demás grupos terapéuticos, en fármacos VINE, EFG y en los de nula o baja mejora terapéutica.Diseño.Estudio transversal, descriptivoEmplazamientoAtención primariaParticipantesFármacos financiables prescritos por y/o solicitados a los médicos de familia de EAP.Resultados principalesSe estudiaron 7.922 fármacos. Tipo de prescripción: PI, 48,3% (IC del 95%, 47,2–49,4); del médico de atención primaria (PRO), 50,6% (IC del 95%, 49,5–51,7); desconocida, 1,1% (IC del 95%, 0,9–1,3). Procedencia principal: especialista público (72,2%), especialista privado (16,6%). Un 62,5% del gasto correspondió a la PI. En el grupo terapéutico más prescrito, sistema nervioso central (24,2%), PI, 39,8%; PRO, 58,9%; en aparato cardiovascular (19,1%), PI, 56,2%, PRO, 43,1%. Se prescribió el fármaco solicitado en un 98,4% de los casos, se cambio en el 1,2% y se suprimió en un 0,4%. Proporción de desacuerdo, 11%; motivos de desacuerdo, no hay necesidad de tratar (23,9%), grupo terapéutico (34,4%), principio activo (13,2%), marca comercial (28,5%). Hubo informe de especialista en un 62,4% de los casos.ConclusionesSe detecta una proporción considerable de prescripción no atribuible a atención primaria y una proporción importante de fármacos que el médico de primaria prescribe sin estar de acuerdo. Sería necesario un sistema que permitiera separar el gasto por niveles, así como mejorar la comunicación entre éstos.ObjectivesMain objetives: to know the proportion of induced prescription (IP) in Area Bilbao and its source, the proportion of cost IP accounts for, the proportion of IP in the main therapeutic groups, the attitude of GP when requested for prescription and its influence on cost, the proportion of disagreement with requested prescription, the reasons for disagreement, and the proportion with letter from specialist. Secondary objectives: to know the proportion of IP in the remaining therapeutic groups, in drugs of low clinical value, in generic drugs and in new drugs with low or no therapeutic improvement.DesignA descriptive cross-sectional study.SettingPrimary health care.ParticipantsDrugs prescribable under National Health Service prescribed by and/or requested to GPs.Main results7.922 drugs were analysed. Type of prescription: IP, 48.3% (95% CI, 47.2–49.4); GP prescription (GPP), 50.6% (95% CI, 49.5–51.7); unknown source, 1,1% (95% CI, 0.9–1.3). Main source, public specialist (72.2%), private specialist (16.6%). IP accounted for 62.5% of cost. In the most prescribed therapeutic group, central nervous system (24.2%), IP, 39.8%; GPP, 58.9%; in cardiovascular system (19.1%), IP, 56.2%; GPP, 43.1%. 98.4% of requested prescription was actually prescribed, 1.2% was changed and 0.4%, suppressed. Proportion of disagreement, 11%; reasons for disagreement, no need for medical treatment (23.9%), therapeutic group (34.4%), active ingredient (13.2%), brand name (28.5%). There was a 62.4% with letter from specialist.ConclusionsPrimary care is not accountable for a substantial proportion of prescription. GP prescribes a considerable proportion of drugs without agreement. It would be necessary a system that allows to separate the cost by care levels and also improve their communication

    The Pseudotransannular Ring Opening of 1-Aminocyclohept-4-ene-derived Epoxides in the Synthesis of Tropane Alkaloids: Total Synthesis of (±)-Ferrugine

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    We have optimized a synthetic approach to (±)-Ferrugine in 8 steps starting from 5-aminocyclohept-1-ene and using the Brønsted acid-catalyzed pseudotransannular ring-opening of the epoxide derived from this cycloheptene as the key step for the construction of the 8-azabicyclo[3.2.1]octane central core. While attempting the enantioselective synthesis of this natural product from enantiopure 2-hydroxy-8-azabicyclo[3.2.1]octane we have found that this compound shows a pronounced tendency to racemize via an achiral symmetric aziridinium intermediate. This racemization side process has been studied in detail using both experimental and computational methods

    Therapeutic Drug Monitoring of Antifungal Drugs: Another Tool to Improve Patient Outcome?

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    Introduction: This study aimed to examine the relationship among adequate dose, serum concentration and clinical outcome in a non-selected group of hospitalized patients receiving antifungals. Methods: Prospective cross-sectional study performed between March 2015 and June 2015. Dosage of antifungals was considered adequate according to the IDSA guidelines, whereas trough serum concentrations (determined with HPLC) were considered adequate as follows: fluconazole > 11\ua0\ub5g/ml, echinocandins > 1\ua0\ub5g/ml, voriconazole 1\u20135.5\ua0\ub5g/ml and posaconazole > 0.7\ua0\ub5g/ml. Results: During the study period, 84 patients (65.4% male, 59.6\ua0years) received antifungals for prophylaxis (40.4%), targeted (31.0%) and empirical therapy (28.6%). The most frequent drug was micafungin (28/84; 33.3%) followed by fluconazole (23/84; 27.4%), voriconazole (15/84; 17.9%), anidulafungin (8/84; 9.5%), posaconazole (7/84; 8.3%) and caspofungin (3/84; 3.6%). Considerable interindividual variability was observed for all antifungals with a large proportion of the patients (64.3%) not attaining adequate trough serum concentrations, despite receiving an adequate antifungal dose. Attaining the on-target serum antifungal level was significantly associated with a favorable clinical outcome (OR = 0.02; 95% CI 0.01\u20130.64; p = 0.03), whereas the administration of an adequate antifungal dosage was not. Conclusions: With the standard antifungal dosage, a considerable proportion of patients have low drug concentrations, which are associated with poor clinical outcome
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