295 research outputs found

    Optimización de sistemas de respuesta dual. una aproximación compromiso

    Get PDF
    Recientemente se han propuesto diversas aproximaciones para la optimización de procesos donde se identifican dos variables respuesta, sin llegar a un concenso en el establecimiento de una solución compromiso ante la presencia de múltiples condiciones contradictorias. Se propone una nueva metodología que toma en cuenta simultáneamente la calidad de las predicciones, las variabilidades relativas y los costos o preferencias asociados a cada respuesta. Se ilustra mediante un ejemplo y los resultados pueden ser replicados utilizando el módulo SOLVER de EXCEL.Several approximations have been recently proposed to optimize processes in which are identified two responses variables, but there is no agreement in the establishment of a compromise solution among the multiples conflicting conditions. We propose a new methodology which takes simultaneously into account the quality of the predictions, the relative variabilities and the cost or preference of each response. An example illustrates the methodology and the results can be replicated using EXCEL SOLVER

    Lightning Impulse Current Tests on Conductive Fabrics

    Get PDF
    Submitted to "Journal of Industrial Textiles"The large amount of electric current associated to lightning discharges is hazardous for living beings, equipment, structures and buildings. To protect those targets against lightning are used Lightning Protection Systems (LPS). However, there are some temporary outdoor activities and backcountry places where an adequate LPS cannot be set up mainly due to the large dimensions of its components and its heavy weight. On the search of light weight lightning protection materials that can be used as part of special LPS, we research some types of electroconductive fabrics by applying high lightning impulse currents in laboratory. The fabric samples checked were pieces of 10 cm x 10 cm: two rip-stop type, a plain-weave, a non-woven and a carbon-impregnated polymeric, all of them obtained commercially. Under laboratory conditions, these samples were subject to subsequent lightning impulse currents registering the voltage and current signals. Optical and scanning electron microscope inspections were performed after tests. Despite some changes visualized as marks left on the fabric surface, the results show that investigated conductive textiles can endure ground currents produced by atmospheric lightning since they withstand the several applied laboratory lightning impulse currents. The outcomes suggest that the weave pattern of the conductive fabric influences the lightning current tolerance, enabling some conductive fabrics to be used in heavy-current applications and as part of personal LPS for outdoor, backcountry and mobile shelters, particularly when lightweight and portability are mandatory

    Trainee-environment interactions that stimulate motivation:A rich pictures study

    Get PDF
    Staying motivated when working and learning in complex workplaces can be challenging. When complex environments exceed trainees' aptitude, this may reduce feelings of competence, which can hamper motivation. Motivation theories explain how intrapersonal and interpersonal aspects influence motivation. Clinical environments include additional aspects that may not fit into these theories. We used a systems approach to explore how the clinical environment influences trainees' motivation and how they are intertwined. We employed the rich pictures drawing method as a visual tool to capture the complexities of the clinical environment. A total of 15 trainees drew a rich picture representing a motivating situation in the workplace and were interviewed afterwards. Data collection and analysis were performed iteratively, following a constructivist grounded theory approach, using open, focused and selective coding strategies as well as memo writing. Both drawings and the interviews were used to reach our results. Trainees drew situations pertaining to tasks they enjoyed doing and that mattered for their learning or patient care. Four dimensions of the environment were identified that supported trainees' motivation. First, social interactions, including interpersonal relationships, supported motivation through close collaboration between health care professionals and trainees. Second, organisational features, including processes and procedures, supported motivation when learning opportunities were provided or trainees were able to influence their work schedule. Third, technical possibilities, including tools and artefacts, supported motivation when tools were used to provide trainees with feedback or trainees used specific instruments in their training. Finally, physical space supported motivation when the actual setting improved the atmosphere or trainees were able to modify the environment to help them focus. Different clinical environment dimensions can support motivation and be modified to create optimal motivating situations. To understand motivational dynamics and support trainees to navigate through postgraduate medical education, we need to take all clinical environment dimensions into account54324225

    Cultivo de piña

    Get PDF
    Se tratan generalidades del cultivo de piña, su origen, zonas de producción, morfología de la planta y condiciones de suelo y clima. Adicional se contemplan la las actividades y tecnologías requeridas para establecer, mantener, cosechar y mercadear el cultivo.Generalities of pineapple cultivation, its origin, production areas, plant morphology and soil conditions and climate are treated. Additionally, the activities and technologies required to establish, maintain, harvest and market the crop are contemplated.Generalities of pineapple cultivation, its origin, production areas, plant morphology and soil conditions and climate are treated. Additionally, the activities and technologies required to establish, maintain, harvest and market the crop are contemplated.naBogot

    Repeated use of rich pictures to explore changes in subjective experiences over time of patients with advanced cancer

    Get PDF
    BACKGROUND: The combination of verbal and visual tools may help unravel the experiences of advanced cancer patients. However, most previous studies have focused on a specific symptom, at only one moment in time. We recently found that a specific visual tool, originating from systems thinking, that is, rich pictures (RPs), could provide a more comprehensive view of the experiences of patients with advanced cancer. AIMS: To examine whether the repeated use of RPs can make changes in subjective experiences of patients living with advanced cancer visible over time. METHODS AND RESULTS: We performed a prospective study with a generic qualitative approach that was mostly informed by the process of grounded theory. We invited patients to make an RP twice, at the start of the study, and again after 2 months. Both RP drawing sessions were directly followed by a semi‐structured interview. Patients with all types of solid tumors, above the age of 18, and with a diagnosis of advanced, incurable cancer, were eligible. Eighteen patients participated and 15 patients were able to draw an RP twice. In eight RP‐sets, considerable differences between the first and second RP were noticeable. Two patterns were distinguished: (1) a change (decline or improvement) in physical health (five patients), and/or (2) a change in the way patients related to cancer (three patients). CONCLUSION: RPs are a valuable qualitative research method that can be used to explore the experiences of patients with advanced cancer, not only at a single point in time but also over time

    Very high rotational frequencies and band termination in 73Br

    Get PDF
    Rotational bands in 73Br have been investigated up to spins of 65/2 using the EUROBALL III spectrometer. One of the negative-parity bands displays the highest rotational frequency 1.85 MeV reported to date in nuclei with mass number greater than 25. At high frequencies, the experimental dynamic moment of inertia for all bands decrease to very low values, indicating a loss of collectivity. The bands are described in the configuration-dependent cranked Nilsson-Strutinsky model. The calculations indicate that one of the negative-parity bands is observed up to its terminating single-particle state at spin 63/2. This result establishes the first band termination case in the A = 70 mass region.Comment: 6 pages, 6 figures, submitted to Phys. Rev. C as a Rapid Communicatio

    Deleción terminal del brazo largo del cromosoma 9 en leucemia promielocítica aguda

    Get PDF
    La Leucemia Promielocítica Aguda (LPA), definida como M3 en la clasificación francesa-americana- británica (FAB)(1), se caracteriza por presentar una translocación cromosómica al azar t(15;17)(q22;q21). En esta translocación se fusionan los receptores del ácido retinoíco ?(? RAR) gen localizado en el cromosoma 17 y el gen PML sobre el cromosoma 15(2). Por otra lado, la deleción del brazo largo del cromosoma 9(9q-) es una alteración rara específica encontrada en (LMA) como una anormalidad única del cariotipo o como un cambio secundario, particularmente junto con t(8;21)(q22;q22)(3,4). La mayoría de ellas son deleciones intersticiales, 9q12 y 9q22; constituyen el sitio más común de ruptura proximal y distal (5)

    Intrinsic regulation of hemangioma involution by platelet-derived growth factor

    Get PDF
    Infantile hemangioma is a vascular tumor that exhibits a unique natural cycle of rapid growth followed by involution. Previously, we have shown that hemangiomas arise from CD133+ stem cells that differentiate into endothelial cells when implanted in immunodeficient mice. The same clonally expanded stem cells also produced adipocytes, thus recapitulating the involuting phase of hemangioma. In the present study, we have elucidated the intrinsic mechanisms of adipocyte differentiation using hemangioma-derived stem cells (hemSCs). We found that platelet-derived growth factor (PDGF) is elevated during the proliferating phase and may inhibit adipocyte differentiation. hemSCs expressed high levels of PDGF-B and showed sustained tyrosine phosphorylation of PDGF receptors under basal (unstimulated) conditions. Inhibition of PDGF receptor signaling caused enhanced adipogenesis in hemSCs. Furthermore, exposure of hemSCs to exogenous PDGF-BB reduced the fat content and the expression of adipocyte-specific transcription factors. We also show that these autogenous inhibitory effects are mediated by PDGF receptor-β signaling. In summary, this study identifies PDGF signaling as an intrinsic negative regulator of hemangioma involution and highlights the therapeutic potential of disrupting PDGF signaling for the treatment of hemangiomas

    DJ-1 contributes to adipogenesis and obesity-induced inflammation

    Get PDF
    Adipose tissue functions as an endocrine organ, and the development of systemic inflammation in adipose tissue is closely associated with metabolic diseases, such as obesity and insulin resistance. Accordingly, the fine regulation of the inflammatory response caused by obesity has therapeutic potential for the treatment of metabolic syndrome. In this study, we analyzed the role of DJ-1 (PARK7) in adipogenesis and inflammation related to obesity in vitro and in vivo. Many intracellular functions of DJ-1, including oxidative stress regulation, are known. However, the possibility of DJ-1 involvement in metabolic disease is largely unknown. Our results suggest that DJ-1 deficiency results in reduced adipogenesis and the down-regulation of pro-inflammatory cytokines in vitro. Furthermore, DJ-1-deficient mice show a low-level inflammatory response in the high-fat diet-induced obesity model. These results indicate previously unknown functions of DJ-1 in metabolism and therefore suggest that precise regulation of DJ-1 in adipose tissue might have a therapeutic advantage for metabolic disease treatment.open0
    corecore