803 resultados para conjunction


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Organic petrology supported by electron microscopical and micro-analytical techniques was applied to organic matter in Proterozoic sediments to better understand hydrothermal processes responsible for ore-grade mineralisation. It was shown that organic maturation was not only closely linked to the geological history of the sediments, but also highlighted heat transfer by convection as differentiated from conduction solely through sediment burial and step-wise subsidence. Water-rock ratios effect organic maturation in hydrothermal systems, and erratic reflectance profiles are indicators of convective heat transfer. Identification and characterisation of organic materials in terms of source rock and migrated hydrocarbons was shown to be a powerful tool in reconstructing the thermal history of sediments, identifying hydrothermal episodes, fluid pathways and heat source in the northern Australian Proterozoic basins. Higher reflectance of organic matter towards the central parts of the Mount Isa Basin and some of the most northerly parts point to proximity to higher heat flow at times, in contrast to relatively low temperatures prevailing in the western parts of the basin, next to the Murphy Inlier. A close correlation shown between peak organic reflectance values and super-sequence boundaries farther highlighted the valuable information to be gained from organic petrology, by allowing the separation of processes responsible for metal dissolution and transportation from those inducing precipitation. (C) 2001 Elsevier Science B.V All rights reserved.

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PURPOSE: To investigate the ability of inversion recovery ON-resonant water suppression (IRON) in conjunction with P904 (superparamagnetic nanoparticles which consisting of a maghemite core coated with a low-molecular-weight amino-alcohol derivative of glucose) to perform steady-state equilibrium phase MR angiography (MRA) over a wide dose range. MATERIALS AND METHODS: Experiments were approved by the institutional animal care committee. Rabbits (n = 12) were imaged at baseline and serially after the administration of 10 incremental dosages of 0.57-5.7 mgFe/Kg P904. Conventional T1-weighted and IRON MRA were obtained on a clinical 1.5 Tesla (T) scanner to image the thoracic and abdominal aorta, and peripheral vessels. Contrast-to-noise ratios (CNR) and vessel sharpness were quantified. RESULTS: Using IRON MRA, CNR and vessel sharpness progressively increased with incremental dosages of the contrast agent P904, exhibiting constantly higher contrast values than T1 -weighted MRA over a very wide range of contrast agent doses (CNR of 18.8 ± 5.6 for IRON versus 11.1 ± 2.8 for T1 -weighted MRA at 1.71 mgFe/kg, P = 0.02 and 19.8 ± 5.9 for IRON versus -0.8 ± 1.4 for T1-weighted MRA at 3.99 mgFe/kg, P = 0.0002). Similar results were obtained for vessel sharpness in peripheral vessels, (Vessel sharpness of 46.76 ± 6.48% for IRON versus 33.20 ± 3.53% for T1-weighted MRA at 1.71 mgFe/Kg, P = 0.002, and of 48.66 ± 5.50% for IRON versus 19.00 ± 7.41% for T1-weighted MRA at 3.99 mgFe/Kg, P = 0.003). CONCLUSION: Our study suggests that quantitative CNR and vessel sharpness after the injection of P904 are consistently higher for IRON MRA when compared with conventional T1-weighted MRA. These findings apply for a wide range of contrast agent dosages.

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In the context of severe economic recession, the Library is compelled to adapt to this changing environment, in order to meet the requirements and demands of users with very specific needs. Taking the pillars of sustainable development as a reference point, and extrapolating them to our domain, we establish the next main goals

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This paper discusses Communication Skills Training for Professionals and Paraprofessionals (ComPro), a program that trains professionals and paraprofessionals to communicate more effectively with their hearing-impaired clientele. This study assesses the usefulness of the ComPro in-service program and student workbook.

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Students who are deaf or hard of hearing have typically had difficulty in mathematics; however, this problem often is overlooked because of difficulties in language and reading abilities. This study aims to identify the most appropriate mathematics curriculum for deaf or hard of hearing students in an oral deaf education program.

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A fast, simple, non-destructive method for the direct screening of polycyclic aromatic hydrocarbons (PAHs) in vegetable oil samples is proposed. The method uses a supercritical fluid extraction (SFE) system coupled on-line with a fluorimetric detector to determine PAHs. This special assembly avoids the main problems encountered in the determination of PAHs in complex matrices such as vegetable oils. PAHs are selectively extracted by using silica gel in the thimble and cleaned up by passage through a C18 column. Interferences are preferentially retained by the silica gel during the SFE process while PAHs are adsorbed in the C18 column and the remainder of the matrix is sent to waste. Finally, the C18 column is purged to remove residual CO2 gas and adsorbed PAHs are recovered by desorption with a solvent. The extracts from positive samples are subsequently analyzed by liquid chromatography (LC) with fluorescence detection. The proposed method allows the confirmation of vegetable oil safety and hence provides a new tool for consumer protection. (C) 2004 Elsevier B.V. All rights reserved.

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Testicular biopsy has been a complementary technique for clinical and research purposes to evaluate reproductive function in males. However, hemorrhage, inflammation, degeneration, and adhesion are factors that might limit the use of this procedure. In order to minimize these potential problems, fibrin glue derived from snake venom, a tissue adhesive with sealing, hemostatic, and healing properties, was used in conjunction with bilateral testicular biopsy with the Tru-Cut needle and was compared with a more conventional technique that uses nylon suture. Thirty mature rams were randomly assigned to three groups of 10 animals each, as follows: nonsurgical control group (no scrotal surgery, or biopsy); biopsy + glue group (fibrin glue on puncture sites and skin incisions) and biopsy + suture group (compression with swab on puncture sites and suturing of skin incision). The surgeries of the rams in the biopsy groups were performed on the same day, which was designated Day 0 for all three groups. Data of scrotal circumference, number of spermatozoa per ejaculum, percentage of morphologically abnormal spermatozoa, spermatozoa motility, and serum testosterone concentrations from Days -7, 20, 40, 60, 80 and 100 were evaluated. There were no significant differences between groups within days for any of the parameters evaluated. In conclusion, the testicular biopsy procedure using the Tru-Cut needle in conjunction with conventional nylon suture or the more novel fibrin glue in rams did not affect any of the parameters of testicular function evaluated in this study and was shown to be relatively simple, safe and efficient. (C) 2002 Published by Elsevier B.V. B.V.

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Aim: To evaluate the influence of a sub-epithelial connective tissue graft placed at the buccal aspect of implants installed immediately after tooth extraction on the dimensional changes of hard and soft tissues. Materials and Methods: In six Labrador dogs a bilateral partial- thickness dissection was made buccal to the second mandibular premolar. At the lingual aspect, full-thickness flaps were elevated. The teeth were extracted and implants installed immediately into the distal socket. A connective tissue graft was obtained from the palate and applied to the buccal aspect of the test sites, whereas contra-laterally, no graft was applied. The flaps were sutured to allow a non-submerged installation. After 4 months of healing, the animals were sacrificed, ground sections were obtained and histomorphometric analyses were performed. Results: After 4 months of healing, all implants were integrated (n = 6). Both at the test and at the control sites bone resorption occurred: 1.6 mm and 2.1 mm, respectively. The difference was not statistically significant. The coronal aspect of the peri-implant soft tissue was wider and located more coronally at the test compared with the control sites. The differences were statistically significant. Conclusions: The application of a connective tissue graft placed at the buccal aspect of the bony wall at implants installed immediately after tooth extraction yielded a minimal preservation of the hard tissues. The peri-implant mucosa, however, was significantly thicker and more coronally positioned at the test compared with the control sites. © 2012 John Wiley & Sons A/S.

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In contrast to formal semantics, the conjunction and is nonsymmetrical in pragmatics. The events in Marc went to bed and fell asleep seem to have occurred chronologically although no explicit time reference is given. As the temporal interpretation appears to be weaker in Mia ate chocolate and drank milk, it seems that the kind and nature of events presented in a context influences the interpretation of the conjunction. This work focuses on contextual influences on the interpretation of the German conjunction und (‘and’). A variety of theoretic approaches are concerned with whether and contributes to the establishment of discourse coherence via pragmatic processes or whether the conjunction has complex semantic meaning. These approaches are discussed with respect to how they explain the temporal and additive interpretation of the conjunction and the role of context in the interpre-tation process. It turned out that most theoretic approaches do not consider the importance of different kinds of context in the interpretation process.rnIn experimental pragmatics there are currently only very few studies that investigate the inter-pretation of the conjunction. As there are no studies that investigate contextual influences on the interpretation of und systematically or investigate preschoolers interpretation of the con-junction, research questions such as How do (preschool) children interpret ‘und’? and Does the kind of events conjoined influence children’s and adults’ interpretation? are yet to be answered. Therefore, this dissertation systematically investigates how different types of context influence children’s interpretation of und. Three auditory comprehension studies were conducted in German. Of special interest was whether and how the order of events introduced in a context contributes to the temporal read-ing of the conjunction und. Results indicate that the interpretation of und is – at least in Ger-man – context-dependent: The conjunction is interpreted temporally more often when events that typical occur in a certain order are connected (typical contexts) compared to events with-out typical event order (neutral contexts). This suggests that the type of events conjoined in-fluences the interpretation process. Moreover, older children and adults interpret the conjunc-tion temporally more often than the younger cohorts if the conjoined events typically occur in a certain order. In neutral contexts, additive interpretations increase with age. 5-year-olds reject reversed order statements more often in typical contexts compared to neutral contexts. However, they have more difficulties with reversed order statements in typical contexts where they perform at chance level. This suggests that not only the type of event but also other age-dependent factors such as knowledge about scripts influence children’s performance. The type of event conjoined influences children’s and adults’ interpretation of the conjunction. There-fore, the influence of different event types and script knowledge on the interpretation process does not only have to be considered in future experimental studies on language acquisition and pragmatics but also in experimental pragmatics in general. In linguistic theories, context has to be given a central role and a commonly agreed definition of context that considers the consequences arising from different event types has to be agreed upon.