915 resultados para Nose.


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Mode of access: Internet.

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"References" at end of each chapter.

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Edaphic factors affect the quality of onions (Allium cepa). Two experiments were carried out in the field and glasshouse to investigate the effects of N (field: 0, 120 kg ha(-1); glasshouse: 0, 108 kg ha(-1)), S (field: 0, 20 kg ha(-1); glasshouse: 0, 4.35 kg ha(-1)) and soil type (clay, sandy loam) on onion quality. A conducting polymer sensor electronic nose (E-nose) was used to classify onion headspace volatiles. Relative changes in the E-nose sensor resistance ratio (%dR/R) were reduced following N and S fertilisation. A 2D Principal Component Analysis (PCA) of the E-nose data sets accounted for c. 100% of the variations in onion headspace volatiles in both experiments. For the field experiment, E-nose data set clusters for headspace volatiles for no N-added onions overlapped (D-2 = 1.0) irrespective of S treatment. Headspace volatiles of N-fertilised onions for the glasshouse sandy loam also overlapped (D-2 = 1.1) irrespective of S treatment as compared with distinct separations among clusters for the clay soil. N fertilisation significantly (P < 0.01) reduced onion bulb pyruvic acid concentration (flavour) in both experiments. S fertilisation increased pyruvic acid concentration significantly (P < 0.01) in the glasshouse experiment, especially for the clay soil, but had no effect on pyruvic acid concentration in the field. N and S fertilisation significantly (P < 0.01) increased lachrymatory potency (pungency), but reduced total soluble solids (TSS) content in the field experiment. In the glasshouse experiment, N and S had no effect on TSS. TSS content was increased on the clay by 1.2-fold as compared with the sandy loam. Onion tissue N:water-soluble SO42- ratios of between five and eight were associated with greater %dR/R and pyruvic acid concentration values. N did not affect inner bulb tissue microbial load. In contrast, S fertilisation reduced inner bulb tissue microbial load by 80% in the field experiment and between 27% (sandy loam) and 92% (clay) in the glasshouse experiment. Overall, onion bulb quality discriminated by the E-nose responded to N, S and soil type treatments, and reflected their interactions. However, the conventional analytical and sensory measures of onion quality did not correlate with %dR/R.

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Genotype, sulphur (S) nutrition and soil-type effects on spring onion quality were assessed using a 32-conducting polymer sensor E-nose. Relative changes in sensor resistance ratio (% dR/R) varied among eight spring onion genotypes. The % dR/R was reduced by S application in four of the eight genotypes. For the other four genotypes, S application gave no change in % dR/R in three, and increased % dR/R in the other. E-nose classification of headspace volatiles by a two-dimensional principal component analysis (PCA) plot for spring onion genotypes differed for S fertilisation vs. no S fertilisation. Headspace volatiles data set clusters for cv. 'White Lisbon' grown on clay or on sandy loam overlapped when 2.9 [Mahalanobis distance value (D2) = 1.6], or 5.8-(D2 = 0.3) kg S ha-1 was added. In contrast, clear separation (D2 = 7.5) was recorded for headspace volatile clusters for 0 kg S hd-1 on clay vs. sandy loam. Addition of 5.8 kg S ha-1 increased pyruvic acid content (mmole g-1 fresh weight) by 1.7-fold on average across the eight genotypes. However, increased S from 2.9 to 5.8 kg ha-1 did not significantly (P > 0.05) influence % dR/R, % dry matter (DM) or total soluble solids (TSS) contents, but significantly (P < 0.05) increased pyruvic acid content. TSS was significantly (P < 0.05) reduced by S addition, while % DM was unaffected. In conclusion, the 32-conducting polymer E-nose discerned differences in spring onion quality that were attributable to genotype and to variations in growing conditions as shown by the significant (P < 0.05) interaction effects for % dR/R.

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In this article, the authors analyze participants' accounts of why they took part in a repeat-interview study exploring newly diagnosed patients' perceptions of diabetes service provision in Lothian, Scotland. The study involved three semistructured in-depth interviews with each patient (N = 40), which spanned a year. The authors provide a thematic discursive analysis of responses to the question, Can I ask you what made you decide to part in the study and why you've stayed involved over the past year? The main themes are (a) recruitment within health contexts ("the nurse said it would help"), (b) altruism ("if it can help somebody"), (c) qualitative research being seen as inherently innocuous ("nothing to lose"), and (d) therapeutic aspects of interviewing ("getting it off my chest"). The analysis contributes both to the qualitative literature about generic research participation and to a germinal literature exploring qualitative health research participation. © 2006 Sage Publications.

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With an ageing population and increasing prevalence of central-nervous system (CNS) disorders new approaches are required to sustain the development and successful delivery of therapeutics into the brain and CNS. CNS drug delivery is challenging due to the impermeable nature of the brain microvascular endothelial cells that form the blood-brain barrier (BBB) and which prevent the entry of a wide range of therapeutics into the brain. This review examines the role intranasal delivery may play in achieving direct brain delivery, for small molecular weight drugs, macromolecular therapeutics and cell-based therapeutics, by exploitation of the olfactory and trigeminal nerve pathways. This approach is thought to deliver drugs into the brain and CNS through bypassing the BBB. Details of the mechanism of transfer of administrated therapeutics, the pathways that lead to brain deposition, with a specific focus on therapeutic pharmacokinetics, and examples of successful CNS delivery will be explored. © 2014 Bentham Science Publishers.

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Acknowledgments This project was financially supported by the US Geological Survey through a cooperative agreement with the University of Wisconsin – Madison. We are indebted to Dave and Jennifer Redell and Paul White from the Wisconsin Department of Natural Resources for collecting the animals used to complete this study and for assisting with data collection. We thank Melissa Behr for assistance with necropsies and NWHC Animal Care Staff for their help with set-up and maintenance of animals. We thank Lobke Vaanholt and Catherine Hambly (University of Aberdeen, Scotland) for their expertise and coordination in the analyses of the DLW blood samples. Funds were used for direct project costs only. Use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the US Government.

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Central nervous system (CNS) drug delivery is often hampered due to the insidious nature of the blood-brain barrier (BBB). Nose-to-brain delivery via olfactory pathways have become a target of attention for drug delivery due to bypassing of the BBB. The antioxidant properties of phytochemicals make them promising as CNS active agents but possess poor water solubility and limited BBB penetration. The primary aim of this study was the development of mesoporous silica nanoparticles (MSNs) loaded with the poorly water-soluble phytochemicals curcumin and chrysin which could be utilised for nose-to-brain delivery. We formulated spherical MSNP using a templating approach resulting in ∼220nm particles with a high surface porosity. Curcumin and chrysin were successfully loaded into MSNP and confirmed through Fourier transformation infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and HPLC approaches with a loading of 11-14% for curcumin and chrysin. Release was pH dependant with curcumin demonstrating increased chemical stability at a lower pH (5.5) with a release of 53.2%±2.2% over 24h and 9.4±0.6% for chrysin. MSNP were demonstrated to be non-toxic to olfactory neuroblastoma cells OBGF400, with chrysin (100μM) demonstrating a decrease in cell viability to 58.2±8.5% and curcumin an IC50 of 33±0.18μM. Furthermore confocal microscopy demonstrated nanoparticles of <500nm were able to accumulate within cells with FITC-loaded MSNP showing membrane localised and cytoplasmic accumulation following a 2h incubation. MSNP are useful carriers for poorly soluble phytochemicals and provide a novel vehicle to target and deliver drugs into the CNS and bypass the BBB through olfactory drug delivery.

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Lo scopo di questo lavoro di tesi è stato quello di studiare l’efficacia e l’applicabilità dello strumento HERACLES II Flash Gas Chromatography Electronic Nose mediante l’analisi di un set molto ampio di campioni di oli d’oliva vergini reperiti presso un concorso nazionale. Nello specifico, mediante elaborazioni di statistica multivariata dei dati, è stata valutata sia la capacità discriminante del metodo per campioni caratterizzati da un diverso profilo sensoriale, sia la correlazione esistente tra l’intensità delle sensazioni percepite per via sensoriale ed i dati ottenuti mediante l’analisi strumentale. La valutazione delle caratteristiche sensoriali dei campioni è stata realizzata in occasione dello stesso concorso da parte di un gruppo di giudici esperti e secondo le modalità stabilite dai regolamenti comunitari. Ogni campione è stato valutato da almeno 8 assaggiatori che hanno determinato l’intensità di caratteristiche olfattive (eventuali difetti, fruttato e note secondarie positive) e gustative (amaro e piccante). La determinazione dei composti volatili, invece, è stata condotta mediante lo strumento HERACLES II Electronic Nose (AlphaMOS), dotato di due colonne cromatografiche caratterizzate da diversa polarità (MXT-5 con fase stazionaria apolare e MXT-WAX con fase stazionaria polare), ciascuna collegata ad un rivelatore di tipo FID. L’elaborazione multivariata dei dati è stata realizzata mediante il software in dotazione con lo strumento.

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Background: Ear, nose and throat foreign bodies (FBs) are common occurrences particularly among children. This study reviewed the clinical spectrum of ENT FBs, their treatment and outcomes as seen in a tertiary health center in North Western Nigeria. Method: The study was a retrospective chart review of patients that were managed for FB impaction in a tertiary health institution in North Western Nigeria over a four year period. Result: There were 239 patients; M: F: 1.2:1. Majority of FB impaction (46.4%) occurred in children. Majority (68.7%) were otic and FBs. 18.0% of the patients had had failed attempted removal by non ENT specialists. About 25% of these patients developed complications. Majority (62.0%) of these complications occurred in the hand of non-ENT medical personnel. Conclusion: Ear, nose and throat foreign bodies are common in North-Western Nigeria with the highest incidence in children. Removal attempts by untrained health professionals and lack of experience in FB management predisposes to complications. Parental education on close monitoring of their children to avoid such incidences and the need to immediately seek an Otorhinolaryngologist to prevent complications are emphasized.