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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

"A spiritual sound, a lonely sound" : leaf music of Southeastern aboriginal Australians, 1890s-1990s

Ryan, Robin Ann, 1946- January 1999 (has links)
Abstract not available
252

Adsorptive stripping voltammetry of trace elements on a glassy carbon mercury film electrode

Pablo, Fleurdelis, University of Western Sydney, Nepean, Faculty of Science and Technology January 1994 (has links)
This thesis describes the development of new adsorptive cathodic stripping voltammetric methods for reliable determination of some trace metals in biological and environmental materials on a glassy carbon mercury film electrode. In particular, the development of these methods involved selection of a suitable complexing agent for the respective metal ion studied, characterization of the electrode processes, investigation of factors affecting the voltammetric response such as concentration and pH of supporting electrolyte, concentration of complexing agent, accumulation potential, accumulation time and electrode rotation rate. Also, organic and inorganic interferences, linear concentration range, and detection limits were carefully considered. Furthermore, the analytical application of the method was demonstrated for each metal in biological and/or environmental materials, after optimization of the sample decomposition procedure. Some conclusions : the results obtained by the AdCSV method for the determination of tin in juices agreed reasonably with those obtained by atomic absorption method; the use of the adsorptive voltammetric technique after dry-ashing and UV treatment of the samples was successfully demonstrated for the determination of vanadium in standard reference materials such as urban particulate matter, peach leaves, apple leaves and bovine liver; and, the use of the adsorptive stripping voltammetric technique, after decomposition of samples by dry-ashing and UV treatment, was successfully demonstrated for the determination of molybdenum in peach leaves, apple leaves and bovine liver samples. / Doctor of Philosophy (PhD)
253

The foliar physiognomic analysis and taphonomy of leaf beds derived from modern Australia rainforest

Greenwood, David Robert. January 1987 (has links) (PDF)
Typescript. Copies of two papers co-authored by the author, in back cover pocket. Bibliography: leaves 128-143.
254

Stress and its effect on absenteeism in primary schools

Leonard, Carl A. R. January 1998 (has links)
Faculty of Education. Bibliography: leaves 142-155.
255

Elevers kunskaper i årskurs 3 om höstlöv och nedbrytningen i naturen.

Pettersson, Carina January 2007 (has links)
<p>Denna undersökning handlar om elevers kunskaper och uppfattningar angående höstlöven och nedbrytning i naturen. Studien har gjorts på två skolor i årskurs 3. Skola A har profilen ”Natur och Miljö” och skola B är en större skola utan profil. Syftet med arbetet är dels att kartlägga elevers föreställningar om nedbrytning i naturen och dels att undersöka hur man kan arbeta med ämnet i skolan för att få en god lärandemiljö. Elever i årskurs 3 intervjuades och resultatet berättar att alla elever är medvetna om lövfällningen. Sedan skiljer sig kunskaperna åt. Hälften av eleverna på skola A förklarar att löven blir till jord. På skola B nämner ingen elev det. Mer än hälften av eleverna på skola A och två på skola B berättar att jord bildas av ätande maskar och småkryp. Skillnaden tror jag beror på att skola A komposterar. De flesta elever anger skolan som kunskapskälla. Genom att tidigare börja arbeta med kretsloppstänkande i skolan så skulle barnens förståelse utvecklas.</p> / <p>This study examines pupils’ knowledge and conceptions concerning the autumn leaves and decomposition in nature. The investigation took place at two schools. School A has the profile ”Nature and Environment” and school B is a larger school without a profile. The purpose of this work is partly to map pupils’ ideas about decomposition in nature and partly to investigate how to work with the subject in school to get a good learning environment. Pupils in third grade were interviewed and the results show that all pupils are conscious of the leaves falling. Half the pupils at school A explain that the leaves become only soil but no one mentioned that at school B. More than half the pupils at school A and two at school B told that soil comes from worms and small animals feeding. I think the difference between the schools depends on the composting at school A. Most pupils state school as a source of knowledge. Talking about the cycle of matter at an earlier stage could develop children’s understanding.</p>
256

Elevers kunskaper i årskurs 3 om höstlöv och nedbrytningen i naturen.

Pettersson, Carina January 2007 (has links)
Denna undersökning handlar om elevers kunskaper och uppfattningar angående höstlöven och nedbrytning i naturen. Studien har gjorts på två skolor i årskurs 3. Skola A har profilen ”Natur och Miljö” och skola B är en större skola utan profil. Syftet med arbetet är dels att kartlägga elevers föreställningar om nedbrytning i naturen och dels att undersöka hur man kan arbeta med ämnet i skolan för att få en god lärandemiljö. Elever i årskurs 3 intervjuades och resultatet berättar att alla elever är medvetna om lövfällningen. Sedan skiljer sig kunskaperna åt. Hälften av eleverna på skola A förklarar att löven blir till jord. På skola B nämner ingen elev det. Mer än hälften av eleverna på skola A och två på skola B berättar att jord bildas av ätande maskar och småkryp. Skillnaden tror jag beror på att skola A komposterar. De flesta elever anger skolan som kunskapskälla. Genom att tidigare börja arbeta med kretsloppstänkande i skolan så skulle barnens förståelse utvecklas. / This study examines pupils’ knowledge and conceptions concerning the autumn leaves and decomposition in nature. The investigation took place at two schools. School A has the profile ”Nature and Environment” and school B is a larger school without a profile. The purpose of this work is partly to map pupils’ ideas about decomposition in nature and partly to investigate how to work with the subject in school to get a good learning environment. Pupils in third grade were interviewed and the results show that all pupils are conscious of the leaves falling. Half the pupils at school A explain that the leaves become only soil but no one mentioned that at school B. More than half the pupils at school A and two at school B told that soil comes from worms and small animals feeding. I think the difference between the schools depends on the composting at school A. Most pupils state school as a source of knowledge. Talking about the cycle of matter at an earlier stage could develop children’s understanding.
257

Growth and Morphogenesis: Quantifying 3D Surface Growth Patterns and Shape Changes in Developing Leaves

Remmler, Lauren 02 February 2012 (has links)
ABSTRACT: Formation of organ shape is an intriguing yet largely unanswered question in developmental biology. Shapes arise as a result of tightly controlled spatial variation in the rates and directions of tissue expansion over the course of development; therefore, quantifying these growth patterns could provide information about the underlying mechanisms of morphogenesis. Here we present a novel technique and computational tools for quantifying growth and shape changes in developing leaves, with a few unique capabilities. This includes the ability to compute growth from three-dimensional (3D) coordinates, which makes this the first method suitable for studying leaf growth in species or mutants with non-flat leaves, as well as small leaves at early stages of development, and allows us to simultaneously capture 3D shape changes. In the following, we apply these methods to study growth and shape changes in the first rosette leaf of Arabidopsis thaliana. Results reveal clear spatiotemporal patterns in growth rates and directionality, and tissue deformation maps illustrate an intricate balance involved in maintaining a relatively flat leaf surface in wild type leaves. Semi-automated tools presented make a high throughput of data possible with this method, and algorithms for generating mean maps of growth will make it possible to perform standardized comparative analyses of growth patterns between wild type and mutants and/or between species. The methods presented in this thesis will therefore be useful for studying leaf growth and shape, to further investigate the mechanisms of morphogenesis.   RÉSUMÉ: Comment un organe acquiert sa forme particulière au cours du développement est une question intéressante mais largement non résolue. La forme d’un organe résulte de la façon dont les taux et directions de croissance de ses tissues varient dans l’espace et dans le temps. Quantifier les motifs de croissance est donc nécessaire pout élucider les mécanismes sous-jacents de la morphogenèse. Nous présentons ici une nouvelle méthodologie pour quantifier la croissance et les changements de forme dans les feuilles en développement. Cette méthodologie s’appuie sur le développement de nouvelles techniques expérimentales et de programmes informatiques, et présente des avantages uniques : la croissance de la surface des feuilles et le changement de forme peuvent être analysés en trois dimensions (3D), pour une longue période et de large déformations. De plus l’analyse de multiples échantillons permet de générer une cartographie moyenne des motifs de croissance à la surface des feuilles au cours de leur développement, ainsi qu’une description quantitative de la déformation des tissus sous l’effet de leur croissance. Dans cette thèse, nous présentons les résultats de croissance et de changements de forme de la première feuille de rosette d'Arabidopsis thaliana au cours de son développement. Les cartes moyennes de croissance révèlent des motifs spatio-temporels évidents tant pour les taux que pour les directions de croissance. De plus, la description de la déformation des tissus démontre l'équilibre complexe impliqué dans le maintien d'une surface relativement plane dans les feuilles. La méthode proposée et les logiciels associés permettra d’effectuer des analyses comparative de la croissance entre feuilles de type sauvage et feuilles de mutants aux formes altérées, afin d’élucider les mécanismes de la morphogenèse foliaire.
258

Lectures labyrinthiques : House of leaves de Mark Z. Danielewski

Rouleau, Nicolas 08 1900 (has links) (PDF)
Dans ce mémoire, nous tenterons de démontrer comment le roman House of Leaves de Mark Z. Danielewski se présente littéralement comme un labyrinthe dans lequel se perdent ses lecteurs et qui s'étend constamment à travers les lectures qu'on peut en faire. House of Leaves met en scène plusieurs narrateurs qui se superposent, les uns commentant les autres. Ces différents niveaux de narration s'interpénètrent, transgressant ainsi leur hiérarchie ontologique. Nous montrerons, en nous appuyant sur les théories de la lecture de Bertrand Gervais, comment cette transgression se fait par le biais d'une forme d'interprétation partageant les caractéristiques de la lecture littéraire. La figure du labyrinthe représente le mieux cette forme d'interprétation et elle est inscrite à même le texte dans les traces de ce qui fonde le travail de lecture d'un des personnages. Pour chaque palier d'interprétation, cette figure représente à la fois, en suivant la métaphore de la lecture littéraire, le texte lu, la lecture elle-même et le discours qui en résulte. Les traits de la figure sont reconnaissables dans chacun des principaux actes d'interprétation et les personnages-interprètes se comportent en accord avec la mise en récit du mythe du labyrinthe. Le texte, par la complexité propre à sa nature labyrinthique, suscite constamment une interprétation chez ses lecteurs. De cette façon, il happe ceux-ci qui, dans une logique d'invagination, viennent à le contenir en eux pour ensuite lui donner une matérialité sous la forme d'un discours pouvant être supporté par toutes sortes de médias. Le labyrinthe se répand sous la forme de ce texte contenu dans le roman de Danielewski, mais menaçant constamment de sortir de ses limites. House of Leaves se veut une œuvre totale utilisant le plus possible toutes les pratiques signifiantes que l'on trouve dans un livre pour perdre le lecteur tout en s'étendant dans d'autres discours, dans d'autres médias. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : House of Leaves, Mark Danielewski, labyrinthe, lecture, interprétation, figure.
259

Dietary vitamin A/precursors and lung cancer risk in Taiwan: with special reference to garland chrysanthemum and sweet potato leaves consumption

Jin, Yi-Ru 22 July 2005 (has links)
In 2004, lung cancer has been the leading cause of cancer death in Taiwan. Many studies demonstrate that vitamin A plays a crucial role in the prevention of lung cancer. However, few epidemiologic studies have examined the association of dietary vitamin A/precursors and lung cancer in Taiwan. Therefore, a case-control study was conducted to investigate the relationship between the consumption of local common foods that are rich in vitamin A/precursors and the risk of lung cancer. The cases were 301 newly diagnosed patients with histopathologically confirmed primary lung cancer. Two control groups were recruited: 602 hospital controls and 602 neighborhood controls. The consumption of 13 food items and vitamin supplements was estimated with the use of a structured food-frequency questionnaire in face-to-face interviews. Adjusted odds ratios (AOR) and the corresponding 95% confidence intervals (CI) were evaluated with controlling for potential confounders, using the conditional logistic regression model. It was found that reduced risk for lung cancer was associated with increased intakes of vitamin A, a-carotene, or b-carotene from various food groups except fruits. However, inverse associations were not observed for vitamin A, a-carotene, or b-carotene intake from various food items, except garland chrysanthemum and sweet potato leaves. On the other hand, retinol intake from food groups or items was not correlated with lung cancer development. Additionally, more servings of vegetables (AOR for the highest versus the lowest quartile = 0.67-0.70, 95% CI = 0.42-1.08, plinear trend = 0.04), garland chrysanthemum (AOR for the highest versus the lowest tertile = 0.58-0.74, 95% CI = 0.37-1.14, plinear trend = 0.01-0.04) and sweet potato leaves (AOR for the highest versus the lowest tertile = 0.43-0.65, 95% CI = 0.28-0.96, plinear trend &#x00A3; 0.03) were associated with the reduced risk for lung cancer. In conclusion, there were protective effects of dietary intake of vitamin A, a-carotene and b-carotene. The vegetables provided higher potential protection against development of lung cancer than the fruits, especially for garland chrysanthemum and sweet potato leaves. Therefore, our findings suggest that more consumption of garland chrysanthemum and sweet potato leaves might reduce the risk of lung cancer in Taiwan.
260

Ανάλυση συστατικών φύλλων Vaccinium corymbosum

Μερμίγκη, Πηνελόπη 19 August 2014 (has links)
Το Vaccinium corymbosum (Ericaceae) είναι ένας ψηλός θάμνος, ο οποίος καλλιεργείται σε περιοχές της Αμερικής και της Ευρώπης για τους υψηλής διατροφικής αξίας καρπούς του (κυανά μύρτιλλα: blueberries). Στη χώρα μας, καλλιέργεια μύρτιλλων γίνεται κυρίως στην περιοχή της Δράμας. Οι περισσότερες μελέτες εστιάζουν στην ανάλυση των συστατικών των καρπών, ενώ η φυτοχημική σύσταση των φύλλων δεν έχει μελετηθεί εκτενώς. Η παρούσα εργασία, στόχο είχε την ανάλυση των κυριότερων φαινολικών συστατικών των φύλλων του φυτού, με χρήση χρωματογραφικών μεθόδων ανάλυσης. Τα αποξηραμένα φύλλα, τα οποία χρησιμοποιήθηκαν στην παρούσα διατριβή, προέρχονται από τις ποικιλίες ‘Bluecrop’ και ‘Patriot’, βιολογικής καλλιέργειας στην περιοχή της Δράμας. Προετοιμάστηκε αφέψημα των αποξηραμένων φύλλων, το οποίο στη συνέχεια εκχυλίστηκε διαδοχικά, με οξικό αιθυλεστέρα (AcOEt) και βουτανόλη (BuOH). Κατόπιν και με σκοπό τον εύκολο προσδιορισμό των φαινολικών ενώσεων, πραγματοποιήθηκε όξινη υδρόλυση (90 oC, 2 h, 50% μεθανόλη) όλων των κλασμάτων: Crude (αφέψημα), AcOEt, BuOH και Aqueous. Η ανάλυση των συστατικών πραγματοποιήθηκε με Υγρή Χρωματογραφία Υψηλής Απόδοσης με Ανιχνευτή Συστοιχίας Φωτοδιόδων (HPLC-DAD) και ύστερα με Υγρή Χρωματογραφία Υπερυψηλής Απόδοσης (UPLC-MS) με Φασματόμετρο Μάζας, το οποίο διαθέτει υβριδικό αναλυτή τετραπόλου – χρόνου πτήσης (Q-TOF). Για την HPLC-DAD ανάλυση χρησιμοποιήθηκε στήλη αντίστροφης φάσης (Luna C-18), με σύστημα βαθμιδωτής έκλουσης με τρείς διαλύτες: διάλυμα οξικού αμμωνίου (CH3COONH4-10 mM), ακετονιτρίλιο και μεθανόλη (Μαργιάννη, 2011). Επιπλέον, για την ποσοτικοποίηση των κυριότερων φαινολικών συστατικών χρησιμοποιήθηκε σύστημα βαθμιδωτής έκλουσης με δύο διαλύτες: διάλυμα CH3COONH4-10 mM και ακετονιτρίλιο (τροποποίηση Tsao et al., 2003). Στην ανάλυση UPLC-ESI-MS χρησιμοποιήθηκε στήλη αντίστροφης φάσης (BEH C18), με σύστημα βαθμιδωτής έκλουσης με δύο διαλύτες: 0.1% μυρμηκικό οξύ σε H2O και ακετονιτρίλιο. Τα αποτελέσματα έδειξαν, αρχικά, ότι κανένα από τα κλάσματα δεν περιέχει ανθοκυανίνες, ενώ το AcOEt κλάσμα είναι περισσότερο εμπλουτισμένο σε φαινολικά συστατικά, σε σχέση με τα άλλα κλάσματα. Με χρήση της UPLC-ESI-MS ανάλυσης, προσδιορίσθηκαν διάφορα συστατικά μεταξύ των οποίων φαινολικά οξέα και φλαβονοειδή. Ενδιαφέρον παρουσίασε το γεγονός ότι το Aqueous κλάσμα περιείχε μόνο φαινολικά οξέα. Η επιλογή της μεθόδου της όξινης υδρόλυσης, φαίνεται να ήταν ικανοποιητική, αφού τα άγλυκα τμήματα των γλυκοζυλιωμένων φλαβονολών, αλλά και τα προϊόντα διάσπασης του εστερικού δεσμού του χλωρογενικού οξέος, προσδιορίσθηκαν εύκολα με την UPLC-ESI-MS ανάλυση. Στα επιμέρους δείγματα ποσοτικοποιήθηκαν, με χρήση HPLC-DAD ανάλυσης τα εξής φαινολικά συστατικά: χλωρογενικό οξύ, ρουτίνη, υπεροζίτης, ισοκερσιτρίνη και κερκετίνη. Συνεπώς, το αφέψημα των καλλιεργούμενων μύρτιλλων είναι μία καλή πηγή φαινολικών συστατικών. / Vaccinium corymbosum (Ericaceae) is a tall shrub, which is cultivated in parts of America and Europe for their fruits (blueberries), which possess high nutritional value. In our country, blueberries are mainly cultivated in the area of Drama. Many studies focus on the analysis of the constituents of fruits, while the phytochemical composition of leaves has not been studied in detail. The present study aimed the analysis of the main components of blueberry leaves, using chromatographic techniques. Dried leaves (var ‘Bluecrop’ and ‘Patriot’) were obtained from the Cooperative ‘‘Biodrama’’. The decoction of dried leaves was prepared and then extracted sequentially with ethyl acetate and butanol. In order to easily identify the phenolic compounds, all fractions (Crude or decoction, AcOEt, BuOH and Aqueous) were hydrolysed in acid conditions (90 oC, 2 h, 50% MeOH). The components of the fractions were analyzed firstly by High Performance Liquid Chromatography with Diode Array Detector (HPLC-DAD) and then with Ultra High Performance Liquid Chromatography (UPLC-MS) with Mass Spectrometry. The mass spectrometer features hybrid quadrupole - time of flight (Q-TOF) analyzer. For the HPLC-DAD analysis a reverse phase column (Luna C-18) was used with a gradient elution system with three solvents: ammonium acetate (CH3COONH4-10 mM), acetonitrile (AcCN) and methanol (MeOH) (Margianni, 2011). Moreover, the quantification of the major phenolic components system was done with a gradient elution system of CH3COONH4-10 mM and AcCN (modified from Tsao et al., 2003). UPLC-ESI-MS was performed on a reverse phase column (BEH C18) with a gradient elution system with two solvents: 0.1% formic acid in H2O and AcCN. Firstly, the results showed that none of the fractions contain anthocyanins while AcOEt fraction is more enriched in phenolic compounds, in comparison to the other fractions. Using UPLC-ESI-MS analysis, we identified several components including phenolic acids and various flavonoids. Interestingly, the Aqueous fraction contained only phenolic acids. The choice of the method of acid hydrolysis appears to be satisfactory for identification purposes, since the aglycones of glycosylated flavonols, and the cleavage products of the chlorogenic acid, was determined easily by UPLC-ESI-MS analysis. The phenolic compounds: chlorogenic acid, rutin, hyperoside, isoquercitrin and quercetin were quantified in blueberry leaf decoction using HPLC-DAD. Therefore, the decoction of cultivated blueberries is a good source of phenolic compounds.

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