ABSTRACT
The purpose of this study was to develop a customized polishing protocol using standard zirconia polishing kit with polishers of different grit and to study their effect on the surface roughness of zirconia and compare it to that of laboratory polished zirconia samples and machine polished titanium implant abutments. Methods: The samples used in this study were 15 zirconia blocks and 10 machine polished titanium implant abutments (5 Biohorizon and 5 MIS). The 15 zirconia blocks were again divided into three groups. The first group consisted of 5 zirconia samples polished by customised polishing protocol (coarse + medium+ fine). The second group consisted of 5 zirconia samples which were sent to lab1 which used Komet company burs and 5 zirconia samples were sent to lab2 which used carborundum burs and sandpaper for polishing. The fourth group consisted of 5 machine polished titanium implants from MIS system and fifth group consisted of 5 machine polished titanium implants from Biohorizon system. After polishing, the mean surface roughness values (Ra) of zirconia samples and titanium implant abutments were calculated quantitatively by optical profilometer and qualitatively by scanning electron microscope (SEM). Results: The mean surface roughness value of customised polishing protocol using coarse+medium+fine polisher was 0.11 µm which was almost equal to the mean surface roughness values of lab1 polished zirconia samples - 0.131 µm and that of machine polished titanium implant abutments –Biohorizon: 0.201 µm MIS: 0.0859 µm and was within the optimal range of 0.2µm. Conclusions: Within the limitations of this study it was concluded that, the mean surface roughness values of zirconia samples polished by customised polishing protocol , lab1 polished samples and machine polished titanium implant abutments were found to be similar & closer to the critical Ra values (0.2µm) suggesting that the chairside polishing of zirconia can be carried out using the customized polishing technique
ABSTRACT
ABSTRACT Lead has been used in a wide range of applications, but in the past decades it became clear that its high toxicity could cause various problems. Studies indicate that exposure to high concentrations of lead can cause harmful damages to humans. To eliminate the usage of lead in electronic products as an initiative towards electronic waste management (e waste), lead free solders were produced with suitable methods by replacing lead. But lead free solders are not preferred as a substitute of lead because they are poor in their mechanical properties such as tensile strength, shear strength and hardness which are ultimately required for a material to resist failure.Nano-Structured materials and coatings offer the potential for Vital improvements in engineering properties based on improvements in physical and mechanical properties resulting from reducing micro structural features by factors of 100 to 1000 times compared to current engineering materials.
ABSTRACT
Los miembros del Task Force pediátrico del Pulmonary Vascular Research Institute (PVRI, su sigla en Inglés) fueron conscientes de la necesidad de desarrollar una clasificación funcional de la hipertensión pulmonar en niños. La clasificación que se propone sigue el mismo patrón y utiliza los mismos criterios de la clasificación de la hipertensión pulmonar específica para adultos de Dana Point. Fue necesario incluir modificaciones para los niños, teniendo en cuenta que la edad, el crecimiento físico y la madurez influyen en la expresión funcional de la enfermedad. Es necesario definir el estado clínico del niño, pues ello facilita revisar la evolución del mismo en una forma consistente y objetiva a medida que él/ella crecen. Particularmente en los niños más jóvenes, se trató de incluir indicadores objetivos como el crecimiento, la necesidad de alimentos suplementarios y los registros de asistencia al colegio y a la guardería. Esto ayuda a monitorear la evolución clínica y la respuesta al tratamiento a través de los años y facilita el desarrollo de algoritmos de tratamiento en estos pacientes. Se presenta un artículo de consenso sobre una clasificación aplicable a los niños con hipertensión pulmonar que se discutió en la reunión anual del PVRI que se llevó a cabo en Panamá en febrero de 2011.
The members of the Pediatric Task Force of the Pulmonary Vascular Research Institute (PVRI) were aware of the need to develop a functional classification of pulmonary hypertension in children. The proposed classification follows the same pattern and uses the same criteria as the Dana Point pulmonary hypertension specific classification for adults. Modifications were necessary for children, since age, physical growth and maturation influences the way in which the functional effects of a disease are expressed. It is essential to encapsulate a child's clinical status, to make it possible to review progress with time as he/she grows up, as consistently and as objectively as possible. Particularly in younger children we sought to include objective indicators such as thriving, need for supplemental feeds and the record of school or nursery attendance. This helps monitor the clinical course of events and response to treatment over the years. It also facilitates the development of treatment algorithms for children. We present a consensus paper on a functional classification system for children with pulmonary hypertension, discussed at the Annual Meeting of the PVRI in Panama City, February 2011.
Subject(s)
Hypertension , Child , Hypertension, PulmonaryABSTRACT
Las clasificaciones actuales de la hipertensión pulmonar han contribuido significativamente al conocimiento de la enfermedad vascular pulmonar, han facilitado ensayos farmacológicos y han mejorado nuestro conocimiento de las cardiopatías congénitas del adulto; sin embargo estas clasificaciones no son aplicables completamente a la enfermedad en el niño. La clasificación que aquí se propone se basa principalmente en la práctica clínica. Los objetivos específicos de esta nueva clasificación son mejorar las estrategias diagnósticas, promover la investigación clínica, mejorar nuestro conocimiento de la patogénesis, de la fisiología y de la epidemiología de la enfermedad y orientar el desarrollo de modelos de la enfermedad humana en el laboratorio y estudios en animales; también puede servir como un recurso docente. Se hace énfasis en los conceptos de maladaptación perinatal, alteraciones del desarrollo e hipoplasia pulmonar como factores causantes de la hipertensión pulmonar pediátrica; así mismo, en la importancia de los múltiples síndromes malformativos congénitos, genéticos y cromosómicos en la presentación de la hipertensión pulmonar pediátrica. La enfermedad vascular pulmonar hipertensiva en niños se divide en diez grandes categorías.
Current classifications of pulmonary hypertension have contributed a great deal to our understanding of pulmonary vascular disease, facilitated drug trials, and improved our understanding of congenital heart disease in adult survivors. However, these classifications are not applicable readily to pediatric disease. The classification system that we propose is based firmly in clinical practice. The specific aims of this new system are to improve diagnostic strategies, to promote appropriate clinical investigation, to improve our understanding of disease pathogenesis, physiology and epidemiology, and to guide the development of human disease models in laboratory and animal studies. It should be also an educational resource. We emphasize the concepts of perinatal maladaptation, maldevelopment and pulmonary hypoplasia as causative factors in pediatric pulmonary hypertension. We highlight the importance of genetic, chromosomal and multiple congenital malformation syndromes in the presentation of pediatric pulmonary hypertension. We divide pediatric pulmonary hypertensive vascular disease into 10 broad categories.
Subject(s)
Humans , Hypertension , Heart Defects, Congenital , Pediatrics , Pulmonary ArteryABSTRACT
Nocardia globerula NHB-2 exhibited an intracellular acetonitrile hydrolysing activity (AHA) when cultivated in nutrient broth supplemented with glucose (10.0 g/l) and yeast extract (1.0 g/l), at pH 8.0, 30 degrees C for 21 hr. Maximum AHA was recorded in the culture containing 0.1 M of sodium phosphate buffer, (pH 8.8) at 45 degrees C for 15 min with 600 micromol of acetonitrile and resting cells of N. globerula NHB-2 equivalent to 1.0 ml culture broth. This activity was stable up to 40 degrees C and was completely inactivated at or above 60 degrees C. About five-fold increase in AHA was observed after optimization of culture and reaction conditions. Under the optimized conditions, this organism hydrolyzed various nitriles and amides such as propionitrile, benzonitrile. acetamide, and acrylamide to corresponding acids. This nitrile/amide hydrolysing activity of N. globerula NHB-2 has potential applications in enzymatic synthesis of organic acids and bioremediation of nitriles and amides contaminated soil and water system.
Subject(s)
Acetonitriles/metabolism , Catalysis , Culture Media , Hydrogen-Ion Concentration , Hydrolysis , Ions/chemistry , Metals/chemistry , Nocardia/drug effects , Substrate Specificity , Temperature , Time FactorsABSTRACT
Studies on the effect of a juvenoid, DPE-28 (2,4-dinitrophenyl-2',6'-di-tertiarybutyl phenyl ether) on biology and behaviour of Cx. quinquefasciatus showed that the developmental duration, sex ratio, mating success and blood feeding were considerably affected by the exposure of larvae and pupae to the compound. Exposure of fourth instar larvae to 0.007 (EI90) and 0.0019 (EI50) ppm of DPE-28 prolonged the duration of pupation by 58.6 and 52.4 hr and delayed the adult emergence by 35.4 and 17.7 hr in males and 36.8 and 21.1 hr in females respectively. Exposure of freshly ecdysed pupae to 10 and 5 ppm delayed the adult emergence with respect to the control by 54.3 and 32.4 hr in males and 55.2 and 33.2 hr in females respectively. The sex ratio of the adults emerged from treated larvae and pupae was also affected. The female mosquitoes that survived from the exposed fourth instar larvae and pupae exhibited a low blood engorgement ratio. This depression in blood feeding was more pronounced in adults emerged from treated pupae than that of treated fourth instar larvae. A significant proportion of adults emerged from treated larvae and pupae were able to feed only partially. Mating success of the treated populations declined considerably when crosses were made between the males and females emerged from treated fourth instar larvae and pupae. The adults emerged from treated larvae and pupae showed a significant reduction in the oviposition.