Microwave plasma chemical vapour deposition diamond nucleation on ferrous substrates with Ti and Cr interlayers

Diamond-coated steel is considered an important issue in synthetic diamond technology due to the great economical importance of enhancing the wear resistance and surface hardness of commercial Fe-based alloys. However, direct diamond coating by chemical vapour deposition (CVD) is rather problematic-adhesion and growth are seriously affected. The use of interlayers is a common approach to minimise these problems. This work reports an investigation on the establishment of good nucleation and growth conditions of diamond films by microwave plasma CVD (MPCVD) on ferrous substrates coated with Ti and Cr interlayers. Commercial grade ferrous substrates were pre-coated with commercial interlayers by sputtering (Ti, Cr) and electroplating (Cr) techniques. Steel substrates led to better results than iron cast substrates. The best films were obtained on Ti pre-coated steel substrate. The results on Cr interlayers pointed to the advantage of electroplating over the physical vapour deposition (PVD) sputtering. From the two selected parameter sets for diamond deposition, the one using lower power level conducted to the best results. Initial roughness and growth parameters were found to counteract on the uniformity of the diamond films. The morphology was studied by scanning electron microscopy (SEM), the roughness was estimated by profilometry, while diamond quality and stress state were evaluated by mu-Raman spectroscopy. (C) 2002 Elsevier Science B.V. All rights reserved

Maior sobrevida em pacientes com marcadores imunogenéticos de rápida progressão para a AIDS: subsídios para a assistência de enfermagem

This study sought subsidies for improving nursing care programs for AIDS patients and aimed to verify the influence of changes in sexual behavior, including the adoption of safe sex practices, associated with the survival of AIDS patients with immunogenetic markers of rapid disease progression. 27 AIDS patients were interviewed, with genetic predisposition to rapid progression to AIDS. Genes were typified through the polymerase chain reaction. In spite of the presence of immunogenetic factors, associated with individual predisposition to a rapid evolution of the disease, changes in sexual behavior, including safe sex practices and antiretroviral therapy, may be related to greater survival. This suggests that counseling, detection of risk attitudes and health education, focusing on positive health behavior, are tools nursing must use with HIV-positive patients, with a view to better quality of life and greater survival among these individuals, even among those with genetic predisposition to rapid disease progression.Los autores buscan apoyo para el perfeccionamiento de programas de enfermería, orientados a pacientes con SIDA. La finalidad de este estudio fue la de verificar la influencia del comportamiento sexual en la supervivencia de pacientes con SIDA, portadores de genes asociados a la rápida progresión de la enfermedad. Fueron estudiados 27 pacientes con SIDA. Las tipificaciones de genes fueron realizadas por la reacción en cadena de la polimerasa. No obstante la presencia de factores inmunogenéticos, asociados a la predisposición individual a la rápida evolución de la enfermedad, cambios en el comportamiento sexual, con prácticas sexuales seguras y el uso de terapia antiretroviral, pueden estar relacionados con mayor supervivencia. La orientación, la detección de actitudes de riesgo y la educación de salud con enfoque en el comportamiento positivo de salud son herramientas que la enfermería debe utilizar con portadores del VIH, buscando la mejor calidad de vida y mayor supervivencia de esos individuos, incluso en aquellos que tienen predisposición genética a la rápida progresión de la enfermedad.Com enfoque em subsídios para o aperfeiçoamento de programas de enfermagem, direcionados a pacientes com aids, o presente estudo foi realizado com o objetivo de verificar a influência do comportamento sexual na sobrevida de pacientes com aids, portadores de genes associados à rápida progressão da doença. Foram entrevistados 27 pacientes com aids, geneticamente predispostos à rápida progressão da doença. As tipificações dos genes foram realizadas pela reação em cadeia da polimerase. Os resultados sugerem que, apesar da presença de fatores imunogenéticos, associados à predisposição individual para rápida evolução da doença, as mudanças do comportamento sexual, com adoção de práticas de sexo seguro, junto ao uso da terapia anti-retroviral, podem estar relacionadas com maior sobrevida. O aconselhamento, a detecção de atitudes de risco e a educação para saúde, enfocando o comportamento positivo de saúde, são ferramentas que a enfermagem deve utilizar a portadores do HIV, visando à melhor qualidade de vida e maior sobrevida desses indivíduos, mesmo naqueles geneticamente predispostos à rápida progressão da doença

Hypericum sp.: essential oil composition and biological activities

Phytochemical composition of Hypericum genus has been investigated for many years. In the recent past, studies on the essential oils (EO) of this genus have been progressing and many of them have reported interesting biological activities. Variations in the EO composition of Hypericum species influenced by seasonal variation, geographic distribution, phenological cycle and type of the organ in which EO are produced and/or accumulated have also been reported. Although many reviews attributed to the characterization as well as biological activities of H. perforatum crude extracts have been published, no review has been published on the EO composition and biological activities of Hypericum species until recently (Crockett in Nat Prod Commun 5(9):1493–1506, 2010; Bertoli et al. in Global Sci Books 5:29–47, 2011). In this article, we summarize and update information regarding the composition and biological activities of Hypericum species EO. Based on experimental work carried out in our laboratory we also mention possible biotechnology approaches envisaging EO improvement of some species of the genus.Fundação para a Ciência e a Tecnologia (FCT) - project PTDC/AGR AAM/70418/2006, SFRH/BD/ 13283/2003