Dissertations / Theses: 'Shoot'

1

Stephenson, Debra Phyllis. "Transfer of training in a shoot-don't-shoot scenario simulation." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/29517.

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2

Robertson, Paul. "Police dilemmas of interpretation and action : the 'shoot/no-shoot dilemma'." Thesis, University of Abertay Dundee, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.650525.

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3

Rivers, Tiffany. "Shoot or Be Shot| Urban America and Gun Violence among African American Males." Thesis, California State University, Long Beach, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10841331.

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Gun homicides are highly concentrated in African American communities and are widespread in urban neighborhoods. African American males are disproportionately victims and perpetrators of gun violence, have a higher propensity to use and carry weapons, and are more likely to die due to gun violence. Few studies, however, provide a detailed account of the history of gun carrying, the value of gun carrying, and the individual and situational factors that lead to or inhibit the use of guns among young African American males.

Based on semi-structured interviews of 11 African American males obtained via snowball sampling, this thesis explains the causes of African American male gun violence, and describes the patterns and decision-making processes around gun carrying and the use of guns (i.e. how gun were introduced, obtained, used or not used, loved, and despised) among African American males in Oakland, California. Based on the sample’s insight, this thesis concludes that strengthening collective efficacy and community-police relationships, providing employment and educational opportunities and resources, implementing mentorship and restorative justice programs, and Crime Prevention Through Experimental Design (CPTED) strategies can reduce gun violence.

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4

Rumbke, Leif. "Run, Shoot, Catch : Kinetik im Computerspiel." Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2009/3328/.

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Die Bedeutung der Bewegung im Computerspiel wird von vielen Seiten immer wieder betont. Dies ist keinesfalls verwunderlich, wenn man sich einmal die „Verben“ vor Augen führt, die den Handlungsraum klassischer Computerspiele konstituieren: „Laufen“, „Schießen“ und „Fangen“ sollen hier nur als Stellvertreter für ein Repertoire an möglichen Aktionen stehen, die allesamt auf der kinetischen Ebene stattfinden. Diese Handlungen erschöpfen sich aber nicht in sich selbst, sondern stellen auch Sinnzusammenhänge unterhalb der Spielelemente her. In den meisten klassischen Games sind es eben diese kinetischen Relationen, welche die singulären Elemente überhaupt erst zu einem diegetischen Spielraum zusammenfügen, und das Spiel so ermöglichen. Umso verwunderlicher mutet es da an, dass dieser Gestaltungsebene von analytischer Seite bislang so wenig Aufmerksamkeit zu Teil wurde. Mein Aufsatz soll an die Möglichkeiten einer kinetischen Perspektive bei der Betrachtung von Computerspielen heranführen und aufzeigen, welches Potential in einer Analyse wie auch der gestalterischen Nutzung dieser bislang weitgehend vernachlässigten Gestaltungsebene liegen könnte.
The significance of movement in computer games has always been emphasized by many views. This is not at all surprising when one considers the verbs describing the actions that occur in classic games: “Running”, “Shooting” and “Catching” are just a taste of the wide array of playing possibilities, all taking place on a level of kinetics. However these are not just words describing movement but rather create significant relations between the elements in the game. In most classic games it is exactly these kinetic correlations that bring together the single elements to create a diegetic space, thereby rendering the game possible. All the more remarkable is the lack of attention this level of design has received from any analytical standpoint. This document should provide an introduction to the possibilities of observing video games from a kinetics point of view, and bring to light what kind of potential lies in a dedicated analysis of this much neglected level of design as well as its utilization in the creative process.

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5

Venn, Peter. "Regulation of shoot apical meristem activity." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/20969/.

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All above ground plant organs initiate or derive from stem cells at the shoot apical meristem. The activity of the shoot apical meristem determines the rate of leaf initiation, which is repressed by the ACTIN RELATED PROTEIN2/3 (ARP2/3) complex in the dark. The ARP2/3 complex is an ancient nucleator of actin filament branches, with roles in a variety of subcellular processes. However, the mechanism by which the ARP2/3 complex regulates shoot apical meristem activity is unknown. In this thesis I show that the increased shoot apical meristem activity of arp3 in prolonged darkness required the polar auxin efflux carrier PIN-FORMED1 (PIN1). Wild-type shoot apical meristem activity was largely unaffected by inhibitors of polar auxin transport in the dark, and a pin1 mutant had similar shoot apical meristem activity to wild-type. By stark contrast, the increased shoot apical meristem activity of arp3 was hypersensitive to inhibitors of polar auxin transport, and abolished in an arp3pin1 double mutant. Furthermore, multiple phenotypes of a brassinosteroid biosynthesis mutant det2, reported to have reduced PIN1 expression and polar auxin transport, were rescued in an arp3det2 double mutant grown in the light. These results indicate that the ARP2/3 complex regulates the activity of PIN1, possibly by facilitating PIN1 endocytosis, and suggest that the ARP2/3 complex is a repressor of brassinosteroid responses. The auxin response factors ARF4 and ARF5 were found to be repressors of shoot apical meristem activity in the same pathway as the ARP2/3 complex. This result led to the proposal of a model where auxin minima, rather than auxin maxima (where ARF4 and ARF5 are active) are required to initiate new leaves at the shoot apical meristem. The increased shoot apical meristem activity of arp3 required sugar, the glucose sensor TOR kinase, and the initial steps of glycolysis which generate precursors for cell wall biosynthesis. In a candidate approach to identify novel transcriptional regulators of dark development, the IND transcription factor was found to repress shoot apical meristem activity redundantly with its homologue HEC2. IND was also found to interact genetically with the phytochrome interacting factors PIF3 and PIF4 to differentially regulate shoot apical meristem activity. Microarray analysis revealed that the primary target of IND is the sugar transporter SWEET15 (upregulated), which promoted shoot apical meristem activity. This research identifies potential avenues for generating crop varieties with increased shoot apical meristem activity in the dark, which might be advantageous in a mulched system, and for generating semi-dwarf crop varieties, by activating a subset of brassinosteroid responses in brassinosteroid deficient crops.

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6

Smith, Dianne J. "They shoot single people, don't they?" [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000520.

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7

Abad, Vivero Ursula Citlalli. "Morphogenesis at the shoot Apical Meristem." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEN088/document.

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Le phénomène de morphogenèse est le fruit de la division des cellules et de leur expansion, qui sont contrôlées de façon différentielle selon les types cellulaires et les tissus. Dans le cas des plantes, le méristème apical caulinaire (MAC) produit de façon continue les organes aériens à partir de primordia qui sont initiés suite à l’accumulation locale d’une hormone végétale, l’auxine. Pour étudier le processus de formation des organes aériens, nous utilisons l’inflorescence d’Arabidopsis thaliana, dont les fleurs sont mises en place selon un patron régulier à partir de cellules dérivées de cellules souches. Au cours de ce processus, ARF5/MP– un facteur de réponse à l’auxine se liant à l’ADN – joue un rôle central. Une fois activé, il induit l’expression des facteurs de transcription LEAFY, AINTEGUMENTA et AINTEGUMENTA-LIKE6, qui sont nécessaires pour la spécification de l’identité florale et pour la croissance proliférative. A l’échelle cellulaire, des excroissances latérales sont initiées suite à des hétérogénéités locales de croissance. Dans les cellules végétales, ces différences sont dues à des modifications de la paroi cellulaire impliquant l’auxine et ses cibles, qui induisent des variations dans la dynamique des microtubules corticaux résultant en des changements de direction de croissance. Dans une moindre mesure, l’auxine diminue la rigidité des parois cellulaires préalablement à la formation d’un nouvel organe, conduisant à des changements de taux de croissance. Ceci est corrélé à l’activation transcriptionnelle de nombreux gènes qui sont impliqués dans les modifications de la paroi. Ainsi, la voie de signalisation de l’auxine régule l’initiation des primordia en intégrant d’une part l’activation d’un réseau de régulation transcriptionnelle et, d’autre part, la rigidité et l’anisotropie de la paroi cellulaire, impactant directement le taux et la direction de croissance.Cette thèse soutient l’idée selon laquelle l’initiation des organes dans le MAC repose sur des boucles de rétroaction là où des changements locaux de propriétés de la paroi cellulaire influent sur le réseau moléculaire. Il est probable que d’autres hormones soient nécessaires afin de canaliser l’initiation des organes
The process of morphogenesis is driven by cell division and expansion, which are controlled ina differential manner among cell types and tissues. In plants, the above ground organs arecontinuously produced by the shoot apical meristem (SAM), where the initiation of newprimordia is triggered by the local accumulation of the plant hormone auxin. We study theprocess of morphogenesis in the inflorescence of Arabidopsis thaliana, where flowers areformed in a regular pattern from the SAM.The DNA-binding auxin response factor ARF5/MP plays a central role in the initiation offlowers. After its activation, it induces the expression of LEAFY, AINTEGUMENTA andAINTEGUMENTA-LIKE6 transcription factors necessary for the specification of floralidentity and proliferative growth. However, at the cellular level, the initiation of lateraloutgrowths depends on regional differences in growth. In plant cells, these processes areregulated via modifications of the cell wall. Auxin and its downstream targets are also involvedin these processes, by activating changes in the dynamics of the cortical microtubules, whichresult in changes in growth direction. Auxin also slightly reduces wall rigidity prior to organoutgrowth in the SAM, which results in changes in growth rate. This is correlated with thetranscriptional activation of a number of cell wall modifying genes.Thus, auxin signaling regulates primordium initiation by integrating the activation of atranscriptional regulatory network and both the stiffness and anisotropy of the cell wall, whichdirectly influence the rate and direction of growth.The findings of this thesis provide evidence indicating that the mechanisms of organ initiationat the SAM involve feedbacks where changes in the local properties of the cell wall influencethe molecular regulation of the transcriptional regulatory network. Our results suggest that thismight require the influence from other hormones, different from auxin, that funnel theinitiation of lateral outgrowths

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8

Sorefan, Karim. "The max4 Shoot Branching Regulator of Arabidopsis." Thesis, University of York, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485139.

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Axillary bud growth is inhibited by auxin produced at the shoot apex and transported down the stem. Removal of the shoot apex by decapitation can release buds from inhibition, and application of auxin to the cut stump can restore bud inhibition. However auxin action is likely to be indirect because auxin does not accumulate in inhibited buds, and therefore requires a second messenger. The max4 mutant of Arabidopsis has increased b,ud growth that leads to increased branching in mature plants. The axillary buds of isolated nodes are also partially resistant to exogenous auxin applied to the apical cut stump. The max4 mutation also partially rescues the branch!ng of the axr3-1 auxin over-responding mutant. The auxin resistant phenotype of the max4 mutant appears to be specific to bud growth because max4 seedlings were only slightly resistant to exogenous auxin, and the max4 mutation did not rescue other auxin related phenotypes of the Bxr3-1 mutant. The phenotype and auxin physiology of the max4 mutant is reminiscent of the/amosus pea mutants. The ramosus1 mutant regulates a graft transmissible signal that interacts with auxin to inhibit bud growth. The max4 and ramosus1 mutant phenotypes are caused by mutations in orthologous genes, encoding a member of the polyene dioxygenase family. All of the family members characterised to date function around a carbon-carbon double bond of polyene chain compounds with cyclic carbon end groups. MAX4 is most related to animal polyene dioxygenases that cleave carotenoid substrates. Possibly the MAX4/RMS1 proteins cleave a carotenoid to produce a novel mobile signal that iFlhibits bud growth, and may act as an auxin second messenger.

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9

Ali, Md Sohrab. "Shoot morphogenesis of Aucuba japonica Thunb. (Cornaceae)." Kyoto University, 2005. http://hdl.handle.net/2433/145007.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第11605号
農博第1461号
新制||農||904(附属図書館)
学位論文||H17||N3998(農学部図書室)
23248
UT51-2005-D354
京都大学大学院農学研究科森林科学専攻
(主査)教授菊澤喜八郎, 教授野渕正, 教授藤田稔
学位規則第4条第1項該当

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10

George, Gilu. "Genotype by environment interaction in shoot branching." Thesis, University of York, 2012. http://etheses.whiterose.ac.uk/2831/.

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Plant development is highly plastic, allowing plants to adapt to constant changes in environmental conditions. An excellent example of developmental plasticity is shoot branching. The final architecture of the shoot system is determined by the integration of environmental cues such as light and nutrients with endogenous cues. In this thesis the effect of Nitrogen (N) availability on Arabidopsis shoot branching was used as a model to investigate plant developmental plasticity. In particular, natural variation in shoot branching response to N supply was investigated using a set of multi parent advanced generation inter cross (MAGIC) lines (Kover et al., 2009). Correlations between traits in a selected group of MAGIC lines revealed several interesting correlations, characterising two strategies for N response. One strategy involved flowering early, maintaining branch numbers of low N, and minimal shift in resource allocation to roots. This was associated with good seed yield and yield retention on low N. An alternative strategy involves late flowering, high branching on high N but low branching on low N, (i.e. high branching plasticity), and a substantial increase in root fraction on Low N. This was associated with high seed yields on high N, but poor yield retention on low N. The molecular basis for these different strategies are currently unknown, but it seems likely that plant hormones are involved. Analysis of bud activation on isolated nodal stem segments provided strong evidence that the regulation of branching by N availability requires strigolactone (SL), and that strigolactone acts by increasing the competition between buds. There was some evidence of strigolatone resistance in a low plasticity MAGIC line. Shoot system architecture is a key factor underlying crop yield, and yield stability under low N input is an agricultural priority. Therefore, in parallel the branching responses of a set of Brassica rapa lines to N limitation were determined. Results highlight many conserved features between Arabidopsis and Brassica, as well as some differences. These comparisons should aid breeding for shoot system architectures that can deliver improved yield under low N.

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11

Babur, John Leland. "Shoot Structure of Boschniakia hookeri Walpers (Orobanchaceae)." PDXScholar, 1995. https://pdxscholar.library.pdx.edu/open_access_etds/4931.

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Boschniakia hookeri Walpers has been found to parasitize the roots of Gaultheria shallon Pursh, Arctostaphylos uva-ursi (l.) Spreng, and Vaccinium ovatum Pursh, all members of the Ericaceae. This is the first documented report of the parasitism of Vaccinium ovatum. The subterranean shoot of B. hookeri originates endogenously from the perennial tubercle of the parasite. The shoot has an eustele, composed of collateral vascular bundles, arranged in four composite fronts and separated by four wide 'leaf gaps.' Pits on metaHylem vessels range from nearly circular to laterally elongated. Rll vessel members have simple perforations. Ouerall, the Hylem of subterranean shoots contained relatively few tracheary elements. Phloem is abundant, with radial series of sieve tube members that have simple sieve plates. Brachysclereids forming large clusters are positioned to both the inside and outside of the vascular bundles. Abundant stomata are present and frequently raised above the shoot surface. RHillary buds along subterranean shoots are capable of producing flowers or branch shoots. Considerable secondary growth occurs in maintained shoots below developing branch shoots. This manifested by the additional production of secondary Hylem and phloem, and the formation of a protective cuticular epithelium. This study of B. hookeri supports the view that the short and fleshy character of the subterranean shoot, increased presence of phloem, reduction of leaves to scales, and a perennial nature are specializations associated with the holoparasitic mode of life.

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12

Meads, Michael Vearl. "Effects of Short Shoot Number and Presence of an Apical Meristem on Rhizome Elongation, New Short Shoot Production, and New Rhizome Meristem Production of Thalassia Testudinum Banks and Solander Ex König Planting Units in Tampa Bay." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4157.

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Thalassia testudinum Banks and Solander ex König is the dominant seagrass in the Gulf of Mexico, Caribbean and the West Coast of Florida, yet little rhizome elongation, new short shoot production, or new rhizome meristem production data has been collected via direct measurement. A study of the rhizome growth of T. testudinum was completed in December 2004 in southern Tampa Bay that determined growth after 26.5 months. Two PVC planting frames each containing four rhizomes with 2 short shoots, two rhizomes with 4 short shoots, and two rhizomes with 8 short shoots were planted next to existing T. testudinum beds at 5 sites (n = 10 planting frames). The rhizome apical meristem was removed from half of each set of short shoot units on each planting frame. Plants initially lacking a rhizome meristem produced more new long shoot meristems than those planted with an intact meristem, and larger planting units produced more new rhizome meristems than smaller ones, P = 0.001 and P < 0.001, respectively. The total number of rhizome meristems per planting unit (new meristems + initial meristem) was greater in plantings initially lacking a long shoot meristem in the 2, 4 and 8 short shoot size classes. Only the two short shoot plants benefited from an intact rhizome meristem at planting time, elongating 66.4 cm versus 60.4 cm for plants initially lacking a rhizome meristem at 26.5 months. In the 4 and 8 short shoot classes, plants that lacked a rhizome meristem at planting outpaced those with a meristem, producing 192.1 and 277.9 for 4 and 8 short shoot plants compared to 120.9 cm and 177.7 cm for plants with a meristem during the same time period. The greatest growth rate increases were due to lateral branching on planting units that lacked a rhizome meristem in the two largest size classes (4 and 8 short shoots); the differences between plants with an intact rhizome meristem and those without with the size classes pooled did not prove to be statistically different, P = 0.112. Differences among the size classes were significant, however, P < 0.001. Analysis of new short shoots was analogous to the results for rhizome elongation, with the presence of an initial rhizome factor proving insignificant, P = 0.401, and the initial number of short shoots factor proving significant, P < 0.001. The rhizome growth, new short shoot production, and new rhizome meristem production data determined by direct measurements in this study appear to be the first planting unit measurements for this species under natural conditions.

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13

Alexander, Debbie L. "The role of corkscrew in maize shoot development." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270001.

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14

Bennett, Tom. "The regulation of shoot branching in Arabidopsis thaliana." Thesis, University of York, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434134.

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15

Wallace, Rick L., and Nakia J. Woodward. "Training Your Librarians to Shoot for the Stars." Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etsu-works/8763.

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Leyser, Henrietta Miriam Ottoline. "An analysis of fasciated mutants of Arabidopsis thaliana and the role of cytokinin in this phenotype." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357803.

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17

Ebida, Aly Ibrahim Aly. "Evaluation of phenotypic stability and salinity tolerance in tissue culture : propagated plants of strawberry (Fragaria x ananassa Duch.) cultivar 'Tioga'." Thesis, Imperial College London, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273270.

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18

Trahan, Adam. "Don't shoot the messenger capital jurors' perceptions of attorneys /." [Bloomington, Ind.] : Indiana University, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3380134.

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Thesis (Ph.D.)--Indiana University, Dept. of Criminal Justice, 2009.
Title from PDF t.p. (viewed on Jul 14, 2010). Source: Dissertation Abstracts International, Volume: 70-12, Section: A, page: 4866. Adviser: Marla R. Sandys.

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19

Shimizu-Sato, Sae, Mina Tanaka, Hitoshi Mori, and 仁志森. "Auxin-cytokinin interactions in the control of shoot branching." Springer Netherlands, 2009. http://hdl.handle.net/2237/11481.

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20

Brockmann, Alexander [Verfasser]. "Shoot-Out-Klauseln : Radikale Trennungsverfahren im Gesellschaftsrecht / Alexander Brockmann." Frankfurt a.M. : Peter Lang GmbH, Internationaler Verlag der Wissenschaften, 2017. http://d-nb.info/1129544370/34.

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21

Boother, Gillian Margaret. "Gibberellins and genetic control of shoot growth in barley." Thesis, University of Bristol, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330035.

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22

Öztig, Lacin Idil [Verfasser], and Thomas [Akademischer Betreuer] Diez. "Why do Border Guards Shoot? An Explanation of Shoot to Kill Policies which Target Illegal Border Crossers / Lacin Idil Öztig ; Betreuer: Thomas Diez." Tübingen : Universitätsbibliothek Tübingen, 2013. http://d-nb.info/1162444681/34.

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23

Johnston, Jennifer Elaine. "Effects of branch pruning on shoot growth of balsam fir." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ35506.pdf.

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Dhaliwal, Harbinder Singh. "Competence and determination during shoot and root organogenesis in vitro." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ38579.pdf.

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Johnston, Jennifer Elaine. "Effects of branch pruning on shoot growth of balsam fir." Thesis, University of New Brunswick, 1997. http://hdl.handle.net/1882/679.

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Poprawka, Tomasz Rajmund. "Characterisation of the regulatory interaction between SHOOT MERISTEMLESS and YABBY3." Thesis, University of East Anglia, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502424.

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Most plant organs are formed post-embryonically in a continuous manner through the activity of highly organised and dynamic structures called meristems. SHOOT MERISTEMLESS (STM), a member of the KNOX gene family, is a key regulatory gene that maintains shoot meristem cells undifferentiated . Based on a transcriptional profiling approach, YABBY3 (YAB3), which is a central regulator of organ polarity, emerged as one of the potential candidates for direct regulation by STM.

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27

Ameyaw, George Akumfi. "Investigations on seed transmission of cacao swollen shoot virus (CSSV)." Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553071.

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Cocoa swollen shoot virus disease (CSSVD) seriously affects cocoa production in Ghana, particularly in the areas of mass infection (AMI) in the Eastern Region whilst the disease continues spreading to areas with scatter outbreaks especially in the Western Region. Reports utilising visible diagnostic symptoms on whether the virus is seed-borne and transmissible to seedlings of cocoa (Theobroma cacao L.) have been conflicting. Studies show that visible viral symptoms are not always manifested on all affected parts of infected cocoa trees due to a period of CSSV latency. In this work, molecular diagnostic techniques involving DNA and RNA based polymerase chain reaction (PCR) methods were utilised with CSSV primers designed from conserved regions of published CSSV sequences to investigate whether CSSV is sexually transmissible from infected parents to developing seeds and seedlings through a series of pollination experiments. The study also evaluated whether pollen could be a source of CSSV infection into seeds and seedlings through cross pollination experiments by using pollen from CSSV infected cocoa trees onto healthy recipients. Robust precautions were taken to avoid cross contamination during duplicated DNA extractions and only those PCR results accompanied by effective positive and negative controls (from CSSV symptomatic and quarantine assured CSSV free trees respectively) were scored. Following DNA extraction all pods obtained from the self pollination experiments involving CSSV infected cocoa trees were found to contain seeds that were PCR positive for CSSV DNA. The pith (mesocarp) of each of the self pollination generated pods was similarly PCR positive for CSSV DNA, though not all seeds from the pods were positive for the PCR screening. Seed components showed diminishing frequencies of CSSV DNA presence in the order: testa> cotyledon> embryo. Sequential DNA samples from new leaves of some of the seedlings derived from the self-pollinated trees are consistently PCR positive for CSSV DNA over 24 months after germination. Nonetheless, a reverse transcription (RT) PCR screening test has been negative for all those PCR positive seedlings indicating absence of CSSV RNA transcripts in the seedlings. None of the seedlings have exhibited symptoms characteristic of CSSV and infectivity tests on them have been negative. Seeds and seedlings from the cross pollination experiments have also been negative for the PCR analysis implying that pollen could not to be a potential route for CSSV infection. Possible explanations for these events including viral DNA integration into the cocoa genome and possible methylation-directed inactivation of the CSSV DNA are discussed.

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Lyndon, Robert Frank. "Growth and development of the root and shoot apical meristems." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/15238.

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Buck-Sorlin, Gerhard Hartwig. "Crown architecture and modelling of oak (Quercus robur L., Q.petraea (Matt.) Liebl.) and sycamore (Acer pseudoplatanus L.)." Thesis, Bangor University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361257.

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Kanakis, Andreas G. "In vitro plant regeneration studies with Capsicum annuum." Thesis, University of Bath, 1987. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380371.

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31

Eiler, Brian A. "The Behavioral Dynamics of Shooter Bias in Virtual Reality: The Role of Race, Armed Status, and Distance on Threat Perception and Shooting Dynamics." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1511798377909988.

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32

Prigge, Michael Jon. "Regulation of Arabidopsis shoot development by the Serrate and Ensalada genes /." view abstract or download file of text, 1999. http://wwwlib.umi.com/cr/uoregon/fullcit?p9947979.

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Thesis (Ph. D.)--University of Oregon, 1999.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 87-98). Also available for download via the World Wide Web; free to University of Oregon users. Address: http://wwwlib.umi.com/cr/uoregon/fullcit?p9947979.

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Andræ, Nils. "Commissioning and validation of small subfields in Step-and-shoot IMRT." Thesis, Stockholm University, Medical Radiation Physics (together with KI), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8316.

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One of the most used irradiation techniques in modern radiation therapy is step-and-shoot IMRT. The accuracy of this technique when delivering complex dose distributions strongly depends on the size of the subfields. The aims of this study is to determine the minimum size of subfields that can be used efficiently in Step-and-Shoot IMRT, to investigate the validation process for beam delivery and treatment planning dose calculations, and to find recommendations for practical clinical implementations.

Two different detectors, a CC04 ion chamber and a SFD stereotactic diode, have been used for measuring head scatter factors in air (Sc), total output factors (Scp) and dose profiles in water for a wide range of field sizes. The measurements were compared to calculations done with a pre-release version of the Nucletron MasterPlanTM v 3.1 treatment planning system that employs a novel, high resolution fluence modelling for both its pencil beam and collapsed cone dose calculation algorithms. Collimator settings were explicitly checked using FWHM film measurements with a build-up sheet of tungsten placed close to the treatment head to reduce the influence from lateral electron transport and geometrical penumbra. An analysis of the influence and sensitivity of Scp for small fields with respect to the linear accelerator source size and shape was also made.

The measurements with the ionization chamber and the stereotactic diode showed good agreements with each other and with the treatment planning system calculations for field sizes larger than 2×2 cm2. For small field sizes, measurements with different detectors yielded different results. Calculations showed agreements with measurements with the smallest detector, provided careful field size calibration and commissioning of calculation parameters. Uncertainties in collimator settings and source characteristics were shown to yield large uncertainties in Scp for fields smaller than 2×2 cm2.

The treatment planning system was found to properly handle small subfields but results were very sensitive to uncertainties in source size, as well as calibration and reproducibility of the collimator settings. Therefore if subfields smaller than 2×2 cm2 are to be used in IMRT extra care should be taken to determine the source characteristics and to calibrate the collimators. The volume of the detectors used for validation of such small fields and the loss of charged particle equilibrium conditions also have to be taken into consideration.

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Lamppu, J. (Jukka). "Scots pine needle longevity and other shoot characteristics along pollution gradients." Doctoral thesis, University of Oulu, 2002. http://urn.fi/urn:isbn:9514268822.

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Abstract Branches of adult Scots pine (Pinus sylvestris L.) trees were sampled from boreal dry pine forests to study needle longevity, its variation and its relation to other shoot characteristics. The stands studied were located along transects from two smelters and one city, e.g. along gradients of pollution impact. Constant needle age structures were assumed and static life-tables generated. Mean needle longevity was calculated as the sum of the proportions of living needle fascicles on the successive annual shoots. It fully incorporated the information of the static life-tables and was preferred to median or maximum ages because of its significantly lower variation. The first half of the shedding span, the duration of the period when the needle survival gradually dropped from 90 to 50 %, proved to validly reflect the changes in the needle age structure. Needle longevity decreased 15-40 % towards the pollution sources along the transects studied. Near the smelters, needle longevity decreased with the increasing needle Fe, or Fe, Ni and Cu concentration that represented the main constituents of the airborne particle emissions. Near the city, needle longevity decreased with the increasing needle N and P concentrations, annual needle mass and needle mass packing and decreasing needle area packing. In the urban forests, needle Mg, P and K concentrations decreased linearly with the decreasing needle survival from the second to the fourth needle age class. Concentrations in the living needles of the fourth age class stayed over 80 % of the average for all the age classes, though needle survival dropped below 50 %. A decreasing needle Mn concentration was detected towards all the emission sources. Leaching, especially from the soil, as a possible cause was discussed. Needle longevity had the lowest variation among the shoot characteristics, which increases its value as a tool in ecological monitoring. Low plasticity in needle longevity could be an acclimation to the ambient environmental conditions and length of the growing season and to maximise the carbon gain per time. Needle longevity decreased and annual needle mass and leaf mass per area increased upwards in the crowns of mature Scots pines, reflecting the acclimation to irradiance.

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35

Herrington, Edward John. "Light quality effects on in vitro shoot proliferation of Spiraea nipponica." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28809.

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The work on Spiraea in vitro shoot cultures was done to determine the feasibility of using light quality to modify endogenous phytohormone balances to decrease apical dominance. Such an effect would enable a reduction in the high levels of exogenous cytokinin benzyladenine (BA) applied in culture and thus reduce potential side-effects. The Spiraea in vitro light quality response was characterized by examining the effects of different light wavelengths on growth. A mixture of red/FR induced rates of shoot proliferation with 0.25 mg/1 BA that were as high as rates obtained under white light with 0.5 mg/1 BA. Shoot quality, as determined by the proportion of shoots 1 cm or longer (useful shoots), was highest under red/FR light. The lowest shoot proliferation rate was observed under blue light. When light wavelengths intermediate between blue and red light (green, yellow, and orange) were applied to explants only minor growth modifications occurred. Green light did not inhibit shoot initiation but inhibited shoot elongation at the 0.5 mg/1 BA level. The efficacy of the light source-filter combinations in the first experiment was studied in two further experiments. With the three light sources (tungsten filament, fluorescent, and metal halide) together with a blue filter, results supported the putative blue light inhibitory effect suggested in the first light quality experiment. Under the red filter, the tungsten filament source induced the highest shoot number means at both BA levels used (0.25 and 0.5 mg/1). Two factors may have contributed to the red/FR effect observed in the first experiment; the time under an incubation light regime before transfer to the treatment regime, and the photon fluence rate of each regime. In the subsequent study to examine these factors, shoot initiation was optimized at the lower BA levels of 0.25 and 0.4 mg/1 when cultures under low fluence red/FR were transferred after four weeks to white light of a higher fluence for one more week. Glyphosate, a known promoter of IAA oxidation, was used to investigate the presumed effect of lowered IAA-cytokinin interactions. Two types of responses to glyphosate occurred, each one dependent on the glyphosate concentration. At the lower glyphosate level (0.087 mg/1), cultures under both light regimes with 0.25 mg/1 of BA, showed a strong inhibition of shoot initiation. This inhibitory effect was overcome in cultures with 0.5 mg/1 of BA and an overall stimulatory response occurred as shoot initiation rates were as much as four-fold higher than in the previous experiments. For both BA levels, changes in shoot number were greater under white light than under red/FR. At the higher glyphosate level (0.2 67 mg/1), the shoot initiation rates were greater than glyphosate-free controls for both BA levels under white light although under red/FR the rates were virtually unchanged from controls. The glyphosate effect investigated for Spiraea cultures appears to be influenced by the levels of the cytokinin BA resulting in pleiotropic effects which depend on the specific concentrations of each component.
Land and Food Systems, Faculty of
Graduate

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36

Holmes, Lisa. "The role of ethylene in shoot gravitropism in sunflower (Helianthus annuus)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ31353.pdf.

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37

Edwards, T. L. "The ecology of the spruce shoot aphid Cinara pilicornis (Homoptera-Aphididae)." Thesis, University of Ulster, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378742.

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38

Bainbridge, Kath. "The role of the Arabidopsis MAX genes in shoot branching control." Thesis, University of York, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423743.

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39

Egekwu, Chioma. "Influence of nitrogen and sink competition on shoot growth of poplar." Thesis, University of Maryland, College Park, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10130093.

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Terrestrial and oceanic biomass carbon sinks help reduce anthropogenic CO₂ emissions and mitigate the long-term effect of increasing atmospheric CO₂. Woody plants have large carbon pools because of their long residence time, however N availability can negatively impact tree responses to elevated CO₂. Seasonal cycling of internal N in trees is a component that contributes to fitness especially in N limited environments. It involves resorption from senescing leaves of deciduous trees and storage as vegetative storage proteins (VSP) in perennial organs. Populus is a model organism for tree biology that efficiently recycles N. Bark storage proteins (BSP) are the most abundant VSP that serves as seasonal N reserves. Here I show how poplar growth is influenced by N availability and how growth is influenced by shoot competition for stored N reserves. I also provide data that indicates that auxin mediates BSP catabolism during renewed shoot growth. Understanding the components of N accumulation, remobilization and utilization can provide insights leading to increasing N use efficiency (NUE) of perennial plants.

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40

Ho, Megan E. "Why did they shoot? The Power of Media with Attribution Theory." Scholarship @ Claremont, 2017. http://scholarship.claremont.edu/scripps_theses/962.

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Mass shootings, whether on a smaller scale or a large scale, take place frequently (LaFraniere, Cohen, & Oppel, 2015). Yet the media only covers a small fraction of crime events, and those selected often gather large amounts of attention. This is problematic because by only focusing on the only most extreme and newsworthy cases, the media distorts the general public's understanding of crime in the United States, and a person's actual likelihood of victimization (Schildkraut & Elsass, 2016). The purpose of the proposed study is to investigate in a nationally represented sample how individuals’ causal attributions for a school shooting with an Asian shooter, as well as whether media influence moderate their attitudes toward the shooter. Participants will be subjected to one of two media conditions, editorial type news or straight news, regarding a shooting and then will answer casual attribution questions and perceptions of the shooter. Participants who judge in-group members as the shooter are predicted to more likely to attribute the crime to external than individuals who judge out-group members. Also, it is predicted that individuals who judge out-group members as a shooter will not be more likely to attribute the crime to internal factors than individuals who judge in-group members. Lastly, it is predicted that editorial type news will influence individuals to attribute the shooting more to both external and internal factors than straight news would. This study may add important information on how media should be portrayed, and further explore attributions that are made against shooters. Implications for future research are also discussed.

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41

Baker, Catherine Craig Meyerowitz Elliot M. "Genetic and genomic studies of shoot and flower growth in Arabidopsis /." Diss., Pasadena, Calif. : California Institute of Technology, 2004. http://resolver.caltech.edu/CaltechETD:etd-12172003-173451.

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42

Lamppu, Jukka. "Scots pine needle longevity and other shoot characteristics along pollution gradients /." Oulu : Oulun Yliopisto, 2002. http://herkules.oulu.fi/isbn9514268822/.

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43

Duong, Hoa Thanh. "Quambalaria shoot blight in Corymbia calophylla: Detection, pathogenicity, and host resistance." Thesis, Duong, Hoa Thanh ORCID: 0000-0001-6183-6141 (2022) Quambalaria shoot blight in Corymbia calophylla: Detection, pathogenicity, and host resistance. PhD thesis, Murdoch University, 2022. https://researchrepository.murdoch.edu.au/id/eprint/64599/.

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Quambalaria shoot blight (QSB) caused by the non-native pathogen Quambalaria pitereka has been recently introduced to south-west Western Australia (SWWA). It affects the leaves, buds, flowers, and fruits of the keystone tree species Corymbia calophylla (marri) and can lead to the death of young trees. This project examined the potential to establish a disease resistance program for marri to QSB by (1) developing qPCR assays for the rapid and sensitive detection of Q. pitereka from plant tissues, (2) investigating the pathogenicity of Q. pitereka isolates collected in SWWA; (3) screening for QSB resistance of 3-month-old seedlings under glasshouse conditions; and (4) estimating the genetic control of growth traits and QSB resistance in four-, and six-year old trees in two common garden trials containing 165 - 170 open-pollinated families from 18 provenances of marri from across its natural range. As disease expression in QSB is similar to myrtle rust (Austropuccinia psidii), in a glasshouse experiment, seedlings were also screened for resistance to myrtle rust to test whether resistance to both diseases is linked. A qPCR assay for the rapid and sensitive detection of Q. pitereka from plant tissues was developed. Inoculation of seedlings with several Q. pitereka isolates demonstrated that they varied in their pathogenicity ranging from those that caused no disease symptoms to ones that were highly pathogenic in seedlings. There were significant differences in resistance to both QSB and myrtle rust between seedling provenances but no significant correlation between resistance to QSB and myrtle rust. In the common garden field trials, narrow-sense heritability for all growth traits and QSB damage were low to moderate (h2 = 0.11 - 0.26). A correlation between QSB damage and growth traits indicated that fastgrowing provenances were less damaged by QSB disease. The genetic correlation between the same traits at four and six years was strong, and the Type-B correlations were strongly positive for all traits. Both disease incidence and disease severity were assessed and gave similar results, but disease incidence is the easiest to assess in older trees. There was poor correlation between the provenance resistance assessed at the seedling stage and trees at four and six years of age. Provenances from cooler wetter regions showed higher resistance in the field trials than those from warmer, drier areas. Results suggest that selection for QSB resistance cannot be assessed in seedlings but may be reliably undertaken by assessing disease incidence on four-year old trees at the earliest. The results of this study indicate a strong potential for a resistance breeding program to develop populations of genetically diverse and resistant trees.

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44

van, Rongen Martin. "The role of auxin transport in the control of shoot branching." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/270648.

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Branching is a highly plastic trait, enabling plants to adapt their growth form in response to environmental stimuli. In flowering plants, shoot branching is regulated through the activity of axillary buds, which grow into branches. Several classes of plant hormones have been shown to play pivotal roles in regulating bud outgrowth. Auxin derived from the primary shoot apex and active branches inhibits bud outgrowth, whereas cytokinin promotes it. Strigolactones also inhibit bud outgrowth, by changing properties of the auxin transport network, increasing the competition between buds. This occurs by modulating access to the polar auxin transport stream (PATS) in the main stem. The PATS provides directional, long distance transport of auxin down the stem, involving basal localisation of the auxin transporter PIN-FORMED1 (PIN1). Buds need to export their auxin across the stem towards the PATS in order to activate, but since PIN1 is mainly expressed in narrow files of cells associated with the stem vasculature, PIN1 itself it is unlikely to facilitate this connectivity. This thesis re-examines the role of auxin transport in the stem, showing that, besides the PIN1-mediated PATS, other auxin transport proteins constitute a more widespread and less polar auxin transport stream, allowing auxin exchange between the PATS and surrounding tissues. Disruption of this transport stream is shown to reduce bud-bud communication and to partially rescue the increased branching observed in strigolactone mutants. Furthermore, it is shown that distinct classes of auxin transport proteins within this stream can differentially affect bud outgrowth mediated by BRANCHED1 (BRC1). BRC1 is a transcription factor proposed to determine bud activation potential. Taken together, the data presented here provide a more comprehensive understanding of the shoot auxin transport network and its role in shoot branching regulation.

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45

Langford, Penny. "The photosynthetic ability of Rosa in vitro." Thesis, University of Bath, 1987. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377366.

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46

Xia, Qun. "Experimental study on vascular differentiation in the shoot apices of herbaceous dicotyledons." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/nq23932.pdf.

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47

McPhee, Christopher Scott. "Investigation of the interaction between root competition and shoot competition in plants." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ36059.pdf.

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48

Ramesar-Fortner, Nicole S. "Physiological control of shoot apical meristem formation in Brassica napus cv Topas." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0020/MQ55286.pdf.

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49

Israelsson, Maria. "Gibberellin homeostasis and biosynthesis in relation to shoot growth in hybrid aspen /." Umeå : Dept. of Forest Genetics and Plant Physiology, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/s307.pdf.

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50

Mellor, Elizabeth Anne. "The role of CORKSCREW I and FILIFOLIUM I in maize shoot development." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424863.

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Dissertations / Theses on the topic 'Shoot'

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