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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.
1

Tall Poppy Syndrome and its effect on work performance

Dediu, Igorevna January 2015 (has links)
The aim of this study was to find out whether employees would perform worse if they perceived their work colleagues to have negative attitudes towards tall poppies (colleagues favoured the fall of tall poppies rather than rewarding tall poppies), thus displaying typical tall poppy syndrome perceptions. Performance measures were: decision-making vigilance, decision-making dependence, decision-making avoidance, problem solving, creativity, service quality, and the personality construct need for affiliation. Control variables were age, tenure and need for achievement. The design of the study was cross-sectional, online surveys were used to collect the data. The link to the survey was distributed using LinkedIn groups and Facebook advertising, yielding a sample of 229 participants. The data was analysed using regression; the results confirmed 3 of the 7 hypotheses. The results indicated that employees working in an environment that favoured the fall of tall poppies, showed lower decision-making dependability and higher decision-making avoidance. Internal service quality was partially confirmed, it was negatively associated with participants working in an environment that favoured the fall of tall poppies, rather than reward; Theories about the contribution New Zealand’s history has made to the development of tall poppy syndrome are considered. Practical implications of the results are discussed. Directions for future studies in industrial and organizational psychology on the effects of tall poppy syndrome on work performance are discussed.
2

Papaver somniferum and P. bracteatum : tissue culture and morphinan alkaloid production

Day, Keith B. January 1987 (has links)
Papaver somniferum plants accumulate the secondary products codeine and morphine. P. bracteatum accumulates their precursor, thebaine. The aims of the project were to use tissue cultures for the production of these alkaloids and for the biotransformation of thebaine to codeine and morphine. Methods were evaluated for the extraction, separation and quantification of mg or mug amounts of morphinan alkaloids from plant material. TLC, IIPLC and RIA were useful. Poppy cells fron a range of seed sources and explants were grown in static and suspension culture. Manipulations were made in atterpts to induce morphinan biogenesis. These included inmobilisation of cells and changes in the growth medium. Morphinans were absent from unspecialised cells in all but one instance. The biotransformation of thebaine was tested in cell suspensions of P. somniferum and Nicotiana alata. Using thebaine (biosynthesised from CO2) these experiments were extended to organs of the P. somniferum plant. A thebaine-biotransfomation product arose in N. alata (but not P. somniferum) suspensions that also arose in excised P. somniferum capsules. A non-specific enzymic activity is proposed. No codeine or morphine were produced. Plant regeneration was demonstrated, in good yield, by embryogenesis fron meristenoid tissue of P. bracteatum. In P. somniferum the process was initiated but was not routinely successful. Regeneration may be useful for plant improvenent via cloning or as a source of variation. On reorganisation into plantlets, capacity for morphinan alkaloid accumulation was realised. Capacity for alkaloid accumulation is discussed in tenns of a requisite minimum level of cytodifferentiation, perhaps of laticifer-like cells. The uptake or binding of radiolabelled morphine by suspension cultures was investigated, since binding may be a reason for failure to detect morphinans in cultures extracted by the usual methods. Evidence was found that exogenous morphine binds to an insoluble fraction in P. somniferum and I. tabacum but cells did not contain any endogenous bound morphincins.
3

The Evolution of Opium and Anesthesia: From the Ancient Sumerians to 1800s.

Techapinyawat, Rheana 15 February 2018 (has links)
A paper submitted to The University of Arizona College of Medicine - Phoenix, History of Medicine course.
4

Phenotypical and genotypical eversporting varieties

Roelofs, Eltjo Tjarks. January 1937 (has links)
Thesis (doctoral)--Rijks-Universiteit te Groningen, 1937. / From: "Genetica", deel 19, alf. 6. Includes bibliographical references (p. 535-536).
5

Molecular systematics of Meconopsis Vig. (Papaveraceae): taxonomy, polyploidy evolution, and historical biogeography from a phylogenetic insight

Xiao, Wei, active 2013 18 February 2014 (has links)
Known as the Himalayan poppies or the blue poppies, Meconopsis is a genus with approximately 50 species distributed through the high altitude of the Himalaya and the Hengduan Mountains (SW China). This dissertation is a study of the systematics of Meconopsis primarily using molecular phylogenetic methods. DNA sequences of chloroplast matK, ndhF, trnL-trnF, rbcL, and nuclear ITS were collected to reconstruct the phylogenies of the genus. Results showed that traditional Meconopsis is a polyphyletic group and revealed extensive mismatches between the nuclear ITS tree and the chloroplast tree. Based on the phylogenies, the taxonomy of Meconopsis was revised, making Meconopsis monophyletic. Four new sections (sect. Meconopsis, sect. Aculeatae, sect. Primulinae, and sect. Grandes) were proposed as well as a species complex (M. horridula). The chloroplast phylogeny and a likelihood method (chromEvol) were applied to ancestral chromosome number estimation to reconstruct the polyploidy evolution history of the genus. The analysis recovered an ancient triploid ancestor shared by sect. Primulinae and sect. Grandes. A low-copy nuclear gene (GAPDH) network of Meconopsis was further reconstructed, which indicated that the ancient triploid ancestor was formed by hybridization. A hypothesis of reticulate history of Meconopsis was also proposed based on the GAPDH network. Using a reconstructed rbcL phylogeny of Ranunculales, the stem group of Meconopsis was estimated at ca. 22 Mya by molecular dating, which coincided with the time of Asian interior desertification and the onset of Asian monsoon. These climatic changes could possibly have been the impetus for the split between Meconopsis and its sister clade. Ancestral area reconstruction was further conducted using likelihood-based methods. The result indicated that Meconopsis originated in the Himalaya, most likely in the west Himalaya, followed by migration to the Hengduan Mountains. / text
6

An investigation into the molecular genetics and cytogenetics of self-incompatibility in Papaver rhoeas L

Wheeler, Mike January 2001 (has links)
No description available.
7

Height control of Eschscholtzia californica using ancymidol, cycocel, and limited inductive photoperiod

Garrett, Elizabeth Carol Bass 21 July 2010 (has links)
Limited inductive photoperiod (LIP) significantly reduced stem length but had no effect on the peduncle length, leaf number, plant diameter, days from seed to first flower or days from start of long days (LD) to first flower in Eschscholtzia californica. However with fewer LD cycles, negative effects associated with LIP included an increasing number of bud abortions and plants remaining vegetative, while the number of axillary buds decreased. Ancymidol [alpha-cyclopropyl-alpha-(4-methoxyphenyl)-5- pyrimidinemethanol] at 35, 45 and 50 ppm reduced stem length, but had no effect on peduncle length. Although plant diameter was significantly reduced, ancymidol had no effect on number of leaves or days to flower. There were no bud abortions, all plants flowered successfully, and there was no negative effect on axillary bud number with the use of ancymidol. Cycocel [(2-chloroethyl) trimethylammonium chloride] had no effect on stem length or the overall plant height in the Eschscholtzia californica. In addition, cycocel proved to be ineffective on associated vegetative growth and reproductive development. / Master of Science
8

Description and control of flowering in California Poppy (Eschscholzia californica)

Carter, Karen Faye January 1986 (has links)
The California poppy (Eschscholzia californica Cham.) has floral marketplace potential provided it can be produced as a well-proportioned potted plant. Its attractive floral display and tolerance of extreme heat and drought make it a good candidate for research aimed at introducing it as a new ornamental crop. The major objectives of this study were to document the apical meristem changes of California poppy during the transition to flowering, to determine the minimum number of inductive long-day (LD) cycles required for induction and initiation of flowering, and to examine the effects of exogenously applied gibberellin (GA₄₊₇) and auxin (NAA) on reproductive and vegetative development. Histological examination of apical meristems exposed to varying numbers of LD cycles revealed many changes commonly associated with the onset of flowering. There was an increase in RNA activity in the apical cells, an enhanced doming of the shoot apex, an increased elongation of primordia internodes, a disruption of the tunica-corpus organization, and the appearance of well-developed branch primordia. Eight to ten LD cycles was identified as the critical range required for successful flowering in California poppy plants when exposure to the inductive photoperiod was begun at the 8 to 12 true, expanded leaf stage. Exogeneous NAA was shown to have no significant effect on final reproductive status or vegetative development of California poppy. GA₄₊₇ application resulted in an enhanced shift toward reproductive development and an increase in stem elongation, but it had little effect on peduncle elongation. These results indicate that stem and peduncle elongation may be controlled by different mechanisms and warrant further research. The final chapter of the thesis concerning the design and evaluation of educational programs for the Virginia Tech Horticultural Gardens represents a departure from the major topic of study. This chapter is the result of the author's interest in, and the Garden's need for, an educational program suitable for the general public. This study can be considered the first step in the development of such an educational program. / Master of Science
9

Extractives from eucomis montana and agapanthus inapertus.

Pillay, Bavani. January 2003 (has links)
Two species belonging to different families were investigated, Eucomis montana from the Hyacinthaceae and Agapanthus inapertus from the Agapanthaceae. To date no previous chemical investigation on Eucomis montana has been reported. Eucomis species are routinely harvested, processed and sold for the treatment of various ailments ranging from toothache, gastro-intestinal ailments, pain-producing ailments and venereal and urinary diseases. Members of the genus have shown to contain steroidal compounds and homoisoflavonoids. In this work one nortriterpenoid, a eucosterol type derivative and eleven homoisoflavonoids belonging to four classes, the 3-benzyl-4-chromanone, the 3-benzyl-3-hydroxy-4-chromanone, the 3-benzylidenyl-4-chromanone and the scillascillin type were found in the bulbs of Eucomis montana. Agapanthus species are also used by a number of African tribes medicinally. The bulbs and rhizomes of this family have been reported to contain steroidal saponins and sapogenins. In this work the roots of Agapanthus inapertus have been investigated and a tignan precursor and a lignan have been found. Structures of the compounds isolated were determined using spectroscopic techniques. / Thesis (M.Sc.)-University of Natal, Durban 2003.
10

Investigations into the analytical applications and fundamental chemistry of the chemiluminescent reactions of Tris(22-bipyridyl)ruthenium(III) with certain Papaver Somniferum alkaloids and other related compounds.

Gerardi, Richard David, mikewood@deakin.edu.au January 1999 (has links)
The reaction of tris(2,2’-bipyridyl)ruthenium(III) (Ru(bipy) <sub>3</sub><sup>3+</sup>) with various analytes to generate chemiluminescence has been well documented. This investigation sought to undertake a chemiluminometic study of the reactions of Ru(bipy) <sub>3</sub><sup>3+</sup> with selected Papaver Somniferum alkaloids and specifically synthesised phenethylamines. The investigation, based on a kinetic study, primarily addressed the effect of varying reaction conditions (pH) on Ru(bipy) <sub>3</sub><sup>3+</sup> chemiluminescence production. To monitor these reactions, a batch chemiluminometer was specifically designed, fabricated and automated to conduct an extensive study on the selected compounds of interest. The instrumentation incorporated a custom built reaction cell and comprised an ‘on-line’ sample preparation system with which calibration standards could be automatically prepared. The instrumentation provided both time-independent (peak area) and time-dependent (kinetic profile) information. A novel approach to the stabilisation of Ru(bipy) <sub>3</sub><sup>3+</sup> as a chemiluminescencent reagent was also investigated and a recirculating system was employed with the batch chemiluminometer to provide a stable supply of Ru(bipy) <sub>3</sub><sup>3+</sup>. Codeine, thebaine and 6-methoxy-codeine were the Papaver Somniferum alkaloids selected for this study and several N-methylated and N,N-dimethylated phenethylamines and methoxy-substituted phenetheylamines were also synthesised to investigate the affect of pH on the chemiluminescence emission efficiency. The versatility of the batch chemiluminometer facilitated the kinetic study of numerous analytes over a broad pH range. The exemplary performance of the chemiluminometer as an analytical instrument, was demonstrated by the calibration functions, based on peak area data, which exhibited excellent linearity and sensitivity. The estimated detection limits (3σ) for the selected alkaloids were in the range 2 x 10&<sup>-9<&/sup;> M to 7 x 10&<sup>-9<&/sup;> at pH 5.0 and above, which compared favourably to detection limits for the same compounds determined using FIA. Relative standard deviations (n=5) for peak areas ranged between 1% to 5% with a mean of 3.1% for all calibration standards above 2.5 x 10&<sup>-8<&/sup;> M. Correlation between concentration and peak area, irrespective of pH and analyte was excellent, with all but two calibration functions having r-squared values greater than 0.990. The analytical figures of merit exemplified the precision and robustness of the reagent delivery and ‘on-line’ sample preparation, as well as the sensitivity of the system. The employment of the chemiluminometer for the measurement of total chemiluminescence emission (peak area) was in itself a feasible analytical technique, which generated highly reproducible and consistent data. Excellent analytical figures of merit, based on peak area, were similarly achieved for the phenethylamines. The effects of analyte structure on chemiluminescence activity was also investigated for the alkaloids and the phenethylamines. Subtle structural variations between the three alkaloids resulted in either a moderately reduced or enhanced total emission that was two or three fold difference only. A significant difference in reaction kinetics was observed between thebaine and codeine/6-methoxy-codeine, which was dependent upon pH. The time-dependent data, namely the observed rate constants for the initial rise in intensity and for the subsequent decay rate, were obtained by fitting a mathematical function (based on the postulated reaction mechanism) to the raw data. The determination of these rate constants for chemiluminescence reactions highlighted the feasibility for utilising such measurements for quantitative analytical applications. The kinetic data were used to discriminate between analyte responses in order to determine the concentrations of individual analytes in a binary mixture. A preliminary, multi-component investigation performed on a binary mixture of codeine and 6-methoxy-codeine (1:1) successfully determined the concentrations of these individual components using such rate constant measurements. Consequently, variations in kinetics resulted in a significant difference between the relative chemiluminescence response based on peak area measurements and the relative response base on peak height measurements obtained using FIA. With regards to the observed reactivity of secondary amines and tertiary amines, chemiluminescence peak area determinations confirmed the vital role of pH on reaction efficiency, which was governed by structural features and kinetics. The tertiary amines investigated generally produced a greater emission under acidic conditions than the corresponding secondary amines. However, the measured chemiluminescence responses were highly dependent upon pH, with similar peak areas obtained for both amine groups under slightly alkaline conditions.

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