230 research outputs found

    Characteristics of high quality ZnO thin films deposited by pulsed laser deposition

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    This paper show that under optimized deposition condition, films can be grown having a full width at half maximum (FWHM) value of the (002) x-ray diffraction (XRD) line a factor of 4 smaller than the previously published results using PLD and among the best reported so far by any technique. Under optimized conditions, c-axis oriented ZnO films having a FWHM value of the (002) XRD reflection line less than 15°, electrical resistivities around 5 × 10-2 Ω cm and optical transmittance higher than 85% in the visible region of the spectrum were obtained. Refractive index was around 1.98 and the Eg = 3.26 eV, values characteristic of very high quality ZnO thin films

    Growth of ZnO thin films on GaAs by pulsed laser deposition

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    ZnO thin films have been grown on GaAs substrates using the pulsed laser deposition technique with or without a photodeposited SiO2 buffer layer. The presence of the SiO2 layer has a beneficial effect on the crystalline quality of the grown ZnO films. Highly c-axis oriented ZnO films having a full width at half maximum value of the (002) X-ray diffraction line of less than 0.13 ° have been grown on such buffer layers at a substrate temperature of only 350 °C

    Effects of laser wavelength and fluence on the growth of ZnO thin films by pulsed laser deposition

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    Transparent, electrically conductive and c-axis oriented ZnO thin films have been grown by the pulsed laser deposition (PLD) technique on silicon and Corning glass substrates employing either a KrF excimer laser (¿ = 248 nm) or a frequency-doubled Nd:YAG laser (¿ = 532 nm). The crystalline structure, surface morphology, optical and electrical properties of the deposited films were found to depend not only on the substrate temperature and oxygen partial pressure, but also on the irradiation conditions. The quality of the ZnO layers grown by the shorter wavelength laser was always better than that of the layers grown by the longer wavelength, under otherwise identical deposition conditions. This behaviour was qualitatively accounted for by the results of the numerical solution of a one-dimensional heat diffusion equation which indicated a strong superheating effect of the melted target material for the case of frequency-doubled Nd:YAG laser irradiations. By optimizing the deposition conditions we have grown, employing the KrF laser, very smooth c-axis oriented ZnO films having a full-width at half-maximum value of the (002) X-ray diffraction value less than 0.16° and optical transmittance around 85% in the visible region of the spectrum at a substrate temperature of only 300°C

    A review of geological effects and damage distribution of the June 9, 1980 Mexicali Valley Earthquake

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    The June 9, 1980 earthquake (M_L = 6.1) occurred on the Cerro Prieto fault located in the Mexicali Valley (Figure 8.1). A day and a half after the event, the area was inspected both from the air and on the ground. The aim of the aerial reconnaissance was to obtain evidence of possible slippage of the Cerro Prieto fault as well as other phenomena related to the earthquake

    Santo Tomás y el gnosticismo

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    El Espíritu Santo en la teología de Santo Tomás de Aquino

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    In recent years, it has been noted from part of specialists in St Thomas’ thought of a growing interest in his biblical commentaries. This essay is part of this movement. The author tries to draw attention of the theology of the Holy Spirit as it is presented not only in the Summa of Theology but also in other writings of the Common Doctor. After presenting a summary of the questions 27 - 36, 37 and 38 of the first part of the ST, the author shows the surprising richness of treatise on the Holy Spirit in the Summa Contra Gentiles, IV. cc. 15 to 26. The central and important role of the Holy Spirit in the life of the Church is studied in an analysis of the comment of Thomas to the Letters of St. Paul, in particular to the Romans and the Gospel of John. To emphasize the dignity of the devotion to the Holy Spirit, the author has added a section on the Gifts of the Holy Spirit, especially in its relationship with the theological and moral virtues, and charisms. A few pages on the New Law and the grace of the Holy Spirit conclude this study. Durante los últimos años se ha podido notar de parte de los especialistas del pensamiento de Santo Tomás un interés creciente en sus comentarios bíblicos. Este ensayo se inscribe en este movimiento. El autor intenta llamar la atención a la teología del Espíritu Santo tal como esta se presenta no solo en la Suma de Teología sino también en otros escritos del Doctor Común. Después de presentar un resumen de las cuestiones 27 - 36, 37 y 38 de la primera parte de la ST, muestra la sorprendente riqueza de los tratados sobre el Espíritu Santo en la Suma contra los Gentiles, IV. cc. 15 a 26. El rol central e importantísimo del Espíritu Santo en la vida de la Iglesia es estudiado en un análisis del comentario de Tomás a las Cartas de san Pablo, en particular a la Carta a los Romanos y del Evangelio según San Juan. Para subrayar la dignidad de la devoción al Espíritu Santo, el autor ha añadido una sección sobre los Dones del Espíritu Santo, en particular en su relación con las virtudes teologales y morales, y con los Carismas. Unas páginas sobre la Ley Nueva como la gracia del Espíritu Santo concluyen este estudio

    Women’s experiences of receiving care for pelvic organ prolapse: a qualitative study

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    Background Pelvic organ prolapse is a common urogenital condition affecting 41–50% of women over the age of 40. To achieve early diagnosis and appropriate treatment, it is important that care is sensitive to and meets women’s needs, throughout their patient journey. This study explored women’s experiences of seeking diagnosis and treatment for prolapse and their needs and priorities for improving person-centred care. Methods Twenty-two women receiving prolapse care through urogynaecology services across three purposefully selected NHS UK sites took part in three focus groups and four telephone interviews. A topic guide facilitated discussions about women’s experiences of prolapse, diagnosis, treatment, follow-up, interactions with healthcare professionals, overall service delivery, and ideals for future services to meet their needs. Data were analysed thematically. Results Three themes emerged relating to women’s experiences of a) Evaluating what is normal b) Hobson’s choice of treatment decisions, and c) The trial and error of treatment and technique. Women often delayed seeking help for their symptoms due to lack of awareness, embarrassment and stigma. When presented to GPs, their symptoms were often dismissed and unaddressed until they became more severe. Women reported receiving little or no choice in treatment decisions. Choices were often influenced by health professionals’ preferences which were subtly reflected through the framing of the offer. Women’s embodied knowledge of their condition and treatment was largely unheeded, resulting in decisions that were inconsistent with women’s preferences and needs. Physiotherapy based interventions were reported as helping women regain control over their symptoms and life. A need for greater awareness of prolapse and physiotherapy interventions among women, GPs and consultants was identified alongside greater focus on prevention, early diagnosis and regular follow-up. Greater choice and involvement in treatment decision making was desired. Conclusions As prolapse treatment options expand to include more conservative choices, greater awareness and education is needed among women and professionals about these as a first line treatment and preventive measure, alongside a multi-professional team approach to treatment decision making. Women presenting with prolapse symptoms need to be listened to by the health care team, offered better information about treatment choices, and supported to make a decision that is right for them

    Does osteoporosis predispose falls? a study on obstacle avoidance and balance confidence

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    Contains fulltext : 96832.pdf (publisher's version ) (Open Access)BACKGROUND: Osteoporosis is associated with changes in balance and physical performance and has psychosocial consequences which increase the risk of falling. Most falls occur during walking; therefore an efficient obstacle avoidance performance might contribute to a reduction in fall risk. Since it was shown that persons with osteoporosis are unstable during obstacle crossing it was hypothesized that they more frequently hit obstacles, specifically under challenging conditions. METHODS: Obstacle avoidance performance was measured on a treadmill and compared between persons with osteoporosis (n = 85) and the comparison group (n = 99). The obstacle was released at different available response times (ART) to create different levels of difficulty by increasing time pressure. Furthermore, balance confidence, measured with the short ABC-questionnaire, was compared between the groups. RESULTS: No differences were found between the groups in success rates on the obstacle avoidance task (p = 0.173). Furthermore, the persons with osteoporosis had similar levels of balance confidence as the comparison group (p = 0.091). The level of balance confidence was not associated with the performance on the obstacle avoidance task (p = 0.145). CONCLUSION: Obstacle avoidance abilities were not impaired in persons with osteoporosis and they did not experience less balance confidence than the comparison group. These findings imply that persons with osteoporosis do not have an additional risk of falling because of poorer obstacle avoidance abilities
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