176 research outputs found

    An online survey of UK women's attitudes to having children, the age they want children and the effect of the COVID-19 pandemic

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    STUDY QUESTION: What are women's views on having children, including the age they want to have them and other influences such as the coronavirus disease 2019 (COVID-19) pandemic? SUMMARY ANSWER: Women's views on having children, at their preferred age of 30 years, included their maternal urge and concerns about their biological clock and stability, while 19% said COVID-19 had affected their views. WHAT IS KNOWN ALREADY: Women globally are delaying the birth of their first child, with the average age of first birth approaching 32 years in some countries. The average age women have their first child in the UK is 30.7 years and over 50% of women aged 30 years are childless. The fertility rate stands at 1.3 in several European Union countries. Some people are not having their desired family size or are childless by circumstance. It is essential to understand people's attitudes to having children in different countries to identify trends so we can develop educational resources in an age-appropriate manner. STUDY DESIGN, SIZE, DURATION: We conducted an anonymous, online survey of multiple choice and open-ended questions. The survey was live for 32 days from 15 May 2020 to 16 June 2020 and was promoted using social media. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 887 women from 44 countries participated in the survey. After filtering out women who did not consent, gave blank or incomplete responses, and those not in the UK, 411 responses remained. From the data, three areas of questioning were analysed: their views on having children, the ideal age they want to have children and the effects of the COVID-19 pandemic. Qualitative data were analysed by thematic analysis. MAIN RESULTS AND THE ROLE OF CHANCE: The average age (±SD) of the women who completed the survey was 32.2 years (±5.9), and they were mainly heterosexual (90.8%) and 84.8% had a university education. One-third of women were married/in a civil partnership (37.7%) and 36.0% were cohabitating. In relation to their views on having children, the main themes identified were: the maternal urge, the ticking of the biological clock, why did no one teach us this?, the need for stability and balance in their life, pressure to start a family and considering other ways to have a family. When asked 'In an ideal world, at what age approximately would you like to have had or have children?' a normal distribution was observed with a mean age of 29.9 (±3.3) years. When asked 'What factors have led you to decide on that particular age?' the most frequent choice was 'I am developing my career'. Three themes emerged from the qualitative question on why they chose that age: the need for stability and balance in their life, the importance of finding the right time and life experiences. The majority of women felt that the COVID-19 pandemic had not affected their decision to have children (72.3%), but 19.1% said it had. The qualitative comments showed they had concerns about instability in their life, such as finances and careers, and delays in fertility treatment. LIMITATIONS, REASONS FOR CAUTION: The survey was promoted on social media only and the women who answered the survey were highly educated. WIDER IMPLICATIONS OF THE FINDINGS: The women surveyed ideally want children at age 30 years but there are obstacles in their way, such as the need to develop their career. Global tailored fertility education is essential to ensure people make informed reproductive choices. In addition, it is essential for supportive working environments and affordable childcare to be in place in every country. STUDY FUNDING/COMPETING INTEREST(S): J.C.H. is founder of www.globalwomenconnected.com and Reproductive Health at Work, and author of the book Your Fertile Years. This project was funded by the Institute for Women's Health, UCL. TRIAL REGISTRATION NUMBER: N/A

    Aplicación de la teoría de robots manipuladores a la biomecánica del brazo humano1

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    ResumenEste artículo presenta la aplicación de un conjunto de técnicas propias de la teoría de los robots manipuladores al estudio del movimiento del brazo humano. Para ello el brazo humano se modela como un robot manipulador redundante. En particular se aplica el concepto de índices de desempeño para predecir posturas óptimas del brazo durante la realización de tareas. En el estudio se incluyen tanto posiciones estáticas, como secuencias de posiciones para la formulación de trayectorias óptimas de movimiento

    Diseño un controlador robusto basado en observador para el modelo lineal de un helicóptero de un grado de libertad (VTOL)

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    Este artículo propone un controlador basado en observador para un modelo de helicóptero tipo VTOL de un grado de libertad. El objetivo de control es mantener la posición del VTOL en un punto de operación, a pesar de las incertidumbres ocasionadas por inexactitud en el modelo y ruido en las mediciones. El controlador y el observador son diseñados con base en algoritmos que inducen modos deslizantes en el sistema en lazo cerrado, ofreciendo características de robustez y convergencia en tiempo finito. Los resultados de simulación muestran un buen desempeño del esquema propuesto tanto en condiciones de ausencia de ruido como cuando se consideran mediciones ruidosas.Universidad Nacional de ColombiaCinvestavColcienciasBanco Mundia

    Analysis of ``Gauge Modes'' in Linearized Relativity

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    By writing the complete set of 3+13 + 1 (ADM) equations for linearized waves, we are able to demonstrate the properties of the initial data and of the evolution of a wave problem set by Alcubierre and Schutz. We show that the gauge modes and constraint error modes arise in a straightforward way in the analysis, and are of a form which will be controlled in any well specified convergent computational discretization of the differential equations.Comment: 11pages LaTe

    Análisis por elementos finitos de una prótesis transtibial para un ciclista paralímpico

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    (Eng) Currently, finite element analysis techniques are used to reduce costs in the manufacturing process of sports prostheses. This study primarily focuses on the finite element analysis of a design for a transtibial prosthesis for a paralympic cyclist, integra ting the biomechanics of an athlete with a double leg amputation below the knee with two prostheses categorized before the Union Cycling International (UCI) with a C - 3 disability and the characteristics of the terrain and the dynamic model. The analysis em ploying finite elements aims to evaluate the static and dynamic behavior of the proposed design when subjected to competition in the track - cycling category. As a result of this analysis, mechanical aspects, such as static forces, buckling, frequency, fatig ue, free fall, impact, and aerodynamics, can be evaluated to verify that the design of the proposed transtibial prosthesis meets an adequate aerodynamic profile and its mechanical characteristics are suitable to be used in a high - performance Paralympic cyc ling competition.(Spa) En la actualidad se emplean técnicas de análisis por elementos finitos para reducir costos en el proceso de fabricación de prótesis deportivas. Este estudio particularmente se centra en el análisis por elementos finitos de un diseño para una prótesis transtibial de un ciclista paralímpico, en el que se integra la biomecánica de un atleta con amputación en ambas piernas por debajo de la rodilla, con dos prótesis categorizado ante la Unión Ciclista Internacional (UCI) con una discapacidad de grado C-3, considerando características del terreno y el modelo dinámico. El análisis por medio de elementos finitos tiene como objetivo evaluar el comportamiento estático y dinámico del diseño propuesto cuando se somete a una competencia en la categoría de ciclismo de pista. Como resultado de este análisis, se pueden evaluar aspectos mecánicos como: esfuerzos estáticos, pandeo, frecuencia, fatiga, caída libre, impacto y aerodinámica, permitiendo verificar que el diseño de la prótesis transtibial propuesto cumple con un perfil aerodinámico idóneo y sus características mecánicas para ser utilizada en una competencia de ciclismo paralímpico de alto rendimiento

    Diagnostic difficulties in congenital tumor with positive antibodies for skeletal muscle. Lipofibromatosis case report

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    Neonatos con Tumores congénitos de partes blandasIntroduction: Congenital soft tissue tumors are uncommon; proper diagnosis calls for histopathological experience and ancillary techniques based upon immunohistochemial, cytogenetic, and molecular biology. Following excision, intermediately aggressive soft tumors tend to local recurrence, which significantly impacts prognosis; some cases occur close to malignity; subsequently, diagnostic implications are enormous for the patient. Case report: A 26-day old neonate with a posterior left thigh mass entered hospital. Initial biopsy analysis could not rule out either striated muscle origin or malignancy; resection and classification of surgical piece followed. Pursuant to resection, using immunohistochemistry panel, tumor analysis and classification took place. Conclusion: Soft tumor diagnosis is a complex process, even more so for newborns. Infrequent occurrence requires that examiners have ample histopathological experience in the handling of ancillary techniques. Furthermore, as in lipofibromatosis, determining the presence of trapped vs. malignant tissue hinders proper classification, which, in turn, has profound implications for the patient. We include a standard diagnostic algorithm based on clinical and histological characteristics for this type of congenital lesions.https://orcid.org/0000-0003-3507-7596https://orcid.org/0000-0001-8932-4877https://orcid.org/0000-0002-7147-425Xhttps://orcid.org/0000-0001-7982-4552Revista Internacional - No indexadaN

    Ecología del Dacnis Turquesa (dacnis hartlaubi) en la zona cafetera de Támesis, Antioquia

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    El Dacnis Turquesa es una especie endémica de Colombia (Hilty y Brown 1996, Stiles 1998), cuya distribución es aparentemente muy restringida y fragmentada (Collar et al. 1992, Hilty y Brown 1996, Botero y Verhelst 2001).BogotáPrograma de Becas para la Conservación de Especies de Fauna y Flor

    Limitaciones y potencialidades del sistema de producción de tomate de árbol en el departamento de Caldas.

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    Se describen y analizan las características sobresalientes del sisema de producción tomate de árbol, Cyphomandra betacea en el departamento de Caldas, con el objeto de entender su nacionalidad y definir alternativas tecnológicas aptas para los agricultores de la región. La toma de información se hizo a través de una encuesta formal difiniendo los límites del sistema a través de unidades espaciales denominadas de referencia. Se analizan los cítricos de competitividad productiva, desarrollo sostenible, equidad y desarrollo tecnológicoTomate-Solanum lycopersicu
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