Academic literature on the topic 'Leaf dissection'
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Journal articles on the topic "Leaf dissection"
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Ke, Jinxiu, Duo Chen, and Yanping Guo. "Designing leaf marginal shapes: Regulatory mechanisms of leaf serration or dissection." Biodiversity Science 26, no. 9 (2018): 988–97. http://dx.doi.org/10.17520/biods.2018127.
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Leng, Yujia, Guoyou Ye, and Dali Zeng. "Genetic Dissection of Leaf Senescence in Rice." International Journal of Molecular Sciences 18, no. 12 (December 11, 2017): 2686. http://dx.doi.org/10.3390/ijms18122686.
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GUNAWARDENA, ARUNIKA H. L. A. N., and NANCY G. DENGLER. "Alternative modes of leaf dissection in monocotyledons." Botanical Journal of the Linnean Society 150, no. 1 (January 2006): 25–44. http://dx.doi.org/10.1111/j.1095-8339.2006.00487.x.
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Holtan, Hans E. E., and Sarah Hake. "Quantitative Trait Locus Analysis of Leaf Dissection in Tomato Using Lycopersicon pennellii Segmental Introgression Lines." Genetics 165, no. 3 (November 1, 2003): 1541–50. http://dx.doi.org/10.1093/genetics/165.3.1541.
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Abstract Leaves are one of the most conspicuous and important organs of all seed plants. A fundamental source of morphological diversity in leaves is the degree to which the leaf is dissected by lobes and leaflets. We used publicly available segmental introgression lines to describe the quantitative trait loci (QTL) controlling the difference in leaf dissection seen between two tomato species, Lycopersicon esculentum and L. pennellii. We define eight morphological characteristics that comprise the mature tomato leaf and describe loci that affect each of these characters. We found 30 QTL that contribute one or more of these characters. Of these 30 QTL, 22 primarily affect leaf dissection and 8 primarily affect leaf size. On the basis of which characters are affected, four classes of loci emerge that affect leaf dissection. The majority of the QTL produce phenotypes intermediate to the two parent lines, while 5 QTL result in transgression with drastically increased dissection relative to both parent lines.
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Blein, Thomas, Véronique Pautot, and Patrick Laufs. "Combinations of Mutations Sufficient to Alter Arabidopsis Leaf Dissection." Plants 2, no. 2 (April 8, 2013): 230–47. http://dx.doi.org/10.3390/plants2020230.
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Wang, Xu-Mei, Xiao-Qi Hou, Yu-Qu Zhang, and Yan Li. "Morphological Variation in Leaf Dissection of Rheum palmatum Complex (Polygonaceae)." PLoS ONE 9, no. 10 (October 28, 2014): e110760. http://dx.doi.org/10.1371/journal.pone.0110760.
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Kellman, Kenneth. "A newly designed dissection needle for making transverse leaf sections." Evansia 22, no. 4 (2005): 118–21. http://dx.doi.org/10.5962/p.346619.
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Gurevitch, Jessica. "VARIATION IN LEAF DISSECTION AND LEAF ENERGY BUDGETS AMONG POPULATIONS OF ACHILLEA FROM AN ALTITUDINAL GRADIENT." American Journal of Botany 75, no. 9 (September 1988): 1298–306. http://dx.doi.org/10.1002/j.1537-2197.1988.tb14190.x.
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Blein, Thomas, Amada Pulido, Aurélie Vialette-Guiraud, Krisztina Nikovics, Halima Morin, Angela Hay, Ida Elisabeth Johansen, Miltos Tsiantis, and Patrick Laufs. "A Conserved Molecular Framework for Compound Leaf Development." Science 322, no. 5909 (December 19, 2008): 1835–39. http://dx.doi.org/10.1126/science.1166168.
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Diversity in leaf shape is produced by alterations of the margin: for example, deep dissection leads to leaflet formation and less-pronounced incision results in serrations or lobes. By combining gene silencing and mutant analyses in four distantly related eudicot species, we show that reducing the function of NAM/CUC boundary genes (NO APICAL MERISTEM and CUP-SHAPED COTYLEDON) leads to a suppression of all marginal outgrowths and to fewer and fused leaflets. We propose that NAM/CUC genes promote formation of a boundary domain that delimits leaflets. This domain has a dual role promoting leaflet separation locally and leaflet formation at distance. In this manner, boundaries of compound leaves resemble boundaries functioning during animal development.
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Descalsota-Empleo, Gwen Iris, Abd Aziz Shamsudin Noraziyah, Ian Paul Navea, Chongtae Chung, Maria Stefanie Dwiyanti, Reuben Jacob Dicen Labios, Asmuni Mohd Ikmal, et al. "Genetic Dissection of Grain Nutritional Traits and Leaf Blight Resistance in Rice." Genes 10, no. 1 (January 8, 2019): 30. http://dx.doi.org/10.3390/genes10010030.
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Colored rice is rich in nutrition and also a good source of valuable genes/quantitative trait loci (QTL) for nutrition, grain quality, and pest and disease resistance traits for use in rice breeding. Genome-wide association analysis using high-density single nucleotide polymorphism (SNP) is useful in precisely detecting QTLs and genes. We carried out genome-wide association analysis in 152 colored rice accessions, using 22,112 SNPs to map QTLs for nutritional, agronomic, and bacterial leaf blight (BLB) resistance traits. Wide variations and normal frequency distributions were observed for most of the traits except anthocyanin content and BLB resistance. The structural and principal component analysis revealed two subgroups. The linkage disequilibrium (LD) analysis showed 74.3% of the marker pairs in complete LD, with an average LD distance of 1000 kb and, interestingly, 36% of the LD pairs were less than 5 Kb, indicating high recombination in the panel. In total, 57 QTLs were identified for ten traits at p < 0.0001, and the phenotypic variance explained (PVE) by these QTLs varied from 9% to 18%. Interestingly, 30 (53%) QTLs were co-located with known or functionally-related genes. Some of the important candidate genes for grain Zinc (Zn) and BLB resistance were OsHMA9, OsMAPK6, OsNRAMP7, OsMADS13, and OsZFP252, and Xa1, Xa3, xa5, xa13 and xa26, respectively. Red rice genotype, Sayllebon, which is high in both Zn and anthocyanin content, could be a valuable material for a breeding program for nutritious rice. Overall, the QTLs identified in our study can be used for QTL pyramiding as well as genomic selection. Some of the novel QTLs can be further validated by fine mapping and functional characterization. The results show that pigmented rice is a valuable resource for mineral elements and antioxidant compounds; it can also provide novel alleles for disease resistance as well as for yield component traits. Therefore, large opportunities exist to further explore and exploit more colored rice accessions for use in breeding.
Dissertations / Theses on the topic "Leaf dissection"
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Viljoen, Jan-Adriaan. "Distribution of leaf dissection and sclerophylly along microhabitat gradients in pteridophytes of the Cape peninsula." Bachelor's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/25976.
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Plant species with small leaves and sclerophylls have been reported to occur mainly on dry, low-nutrient soils in situations of high insolation. However; a number of physiological functions have been proposed for the two sets of traits. Ferns are well-suited to the study of leaf structure and its impact in different environments, as they show remarkable variation in leaf dissectedness and sclerophylly, and are able to inhabit a variety of marginal habitats. In this study, ecological and leaf trait data were collected for 17 fern species occurring in Skeleton Gorge, Table Mountain, in the Western Cape. Correlations between the traits and regressions of leaf traits on potential environmental determinants was carried out using both species averages and phylogenetically independent contrasts. The habitat and leaf traits were also subjected to a test of evolutionary trait conservatism. Sclerophyllous plants were found to be have thicker leaves, containing less chlorophyll, but sclerophylly was poorly correlated with leaf dissection. Plants occurring in high-light environments tended to be more sclerophyllous and have more dissected leaves, although these environments also were nutrient-poor. Leaf dissection appears to be primarily a means of dissipating heat by convection, rather than evaporative cooling, but it may also improve nutrient acquisition in low-nutrient soils. Sclerophylly in these ferns was not directly associated with nutrients; instead low sclerophylly seems to be favoured in low-light environments, perhaps because of lower metabolic costs or to reduce self-shading.
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Dignat, Grégoire. "Dissection génétique de la croissance foliaire et de ses composantes écophysiologiques chez le maïs." Thesis, Montpellier, SupAgro, 2012. http://www.theses.fr/2012NSAM0041.
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L'objectif de cette thèse était d'analyser le déterminisme génétique de la croissance foliaire (LER) du maïs (Zea mays L.). Nous avons combiné plusieurs approches visant à (i) résumer l'information génétique tirée de trois populations de cartographie de QTL (une d'origine tropicale et deux tempérées), (ii) tester l'effet de l'introgresssion de diversité allélique dans les QTL les plus prometteurs, (iii) évaluer jusqu'à quel point les QTL de croissance foliaire affectent la croissance d'autres organes de la plante (iv) disséquer des QTLs d'intérêt par cartographie fine ou génétique d'association locale. La première partie de ce travail concerne le déterminisme génétique de la croissance foliaire maximale (LERmax) évaluée dans des conditions optimales la nuit. LERmax, telle que mesurée en plateforme de phénotypage, partage dans une forte proportion, son contrôle génétique avec la croissance d'autres organes. Des QTL qui affectaient LERmax ou/et la croissance d'autres organes ont alors été disséqués. Une région génomique a été cartographiée avec 23 lignées quasi-isogéniques (NILs) séquentiellement introgressées dans les bins 1.10-11, réduisant ainsi l'intervalle de confiance du QTL d'un facteur 3. Une seconde région génomique a été analysée par une méthode innovante fondée sur une étude d'association ciblée sur une région génomique dans un série allélique générée par introgression de 62 allèles donneurs tirés des lignées parentales d'hybrides cultivés et de populations historiques de maïs d'Amérique Latine dans une lignée élite. L'étude d'association dans cette région relativement petite révèle plus de polymorphismes causaux qu'attendus (six SNP en faible déséquilibre de liaison vs trois QTL consensus).La seconde partie de ce travail considère la sensibilité de la croissance foliaire à la demande évaporative et au déficit hydrique du sol. Un détermisme génétique commun aux deux sensibilités a été mis en évidence par méta-analyse de QTLs initialement détectés dans trois populations en ségrégation et par le test de NILs. Huit métaQTL situés dans quatre régions génomiques ont été testés avec 6 à 17 allèles introgressés pour identifier des NILs qui manifestaient les plus forts effets sur le phénotype. Nous avons initié une cartographie fine dans une de ces régions génomiques à partir d'une populations de recombinants issues de l'introgresssion d'un donneur d'origine tropicale dans B73The objective of this thesis was to analyze the genetic control of the Leaf Elongation Rate (LER) of maize (Zea mays L.). We combined approaches that (i) summarize the QTL information of three mapping populations (one tropical, two temperate), (ii) tested the impact of the introgression of allelic diversity at most promising QTLs, (iii) test to what extent QTLs of LER affect different traits (iv) dissect QTLs of interest by fine mapping or local association mapping.The first part of this document focuses on the genetic control of maximum LER (LERmax) measured in near-optimal conditions during the night. LERmax, as measured in a phenotyping platform, shares an appreciable proportion of its genetic control with the growth abilities of other organs. QTLs affecting LERmax and/or the growth of other organs were therefore dissected. One genomic region was fine-mapped with 23 Near-Isogenic Lines (NILs), sequentially introgressed in the bins 1.10-11, resulting in a reduction of the confidence interval by a factor 3. A second genomic region was analysed after the development of an innovative method of local association mapping on a collection of NILs, introgressed with 62 donor parents from historical populations from different altitude and latitudes in Latin America. This relatively small region harbors more causal polymorphisms than expected (six associated markers in low linkage disequilibrium vs three cQTLs).The second part focuses on the sensitivities of LER to evaporative demand or to soil water deficit. The two sensitivities share a large part of their genetic control as demonstrated by a metaQTL analysis on three mapping populations and the test of NILs. Eight metaQTLs in four genomic regions were tested with 6 to 17 different alleles to find the NILs that best impact the phenotype. We started a fine mapping on one genomic region by using one population of NILs involving a tropical donor
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Dechaumet, Sylvain. "Dissection métabolique de la sénescence foliaire et de la remobilisation des nutriments chez le colza (Brassica napus)." Thesis, Rennes, Agrocampus Ouest, 2018. http://www.theses.fr/2018NSARC133/document.
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Le colza est une culture oléagineuse très exigeante en intrants azotés associée à une faible efficience d’usage de l’azote (EUA). Le défi majeur vise à améliorer le bilan agroenvironnemental du colza par une optimisation de l’EUA, notamment en condition où l’azote est limitant dans le sol. L’EUA est limitée par une faible efficience de remobilisation de l’azote (ERA) lors de la sénescence des feuilles. L’objectif de ce travail de thèse a consisté à rechercher, chez le colza, la topologie et l’orientation des attributs métaboliques associées à l’ERA pendant la sénescence foliaire.Les résultats montrent que le métabolome des feuilles évolue tout au long de leur développement végétatif, de leur croissance à leur chute. Il est spécifique à chaque étage foliaire et traduit des relations trophiques et environnementales particulières liées au positionnement des feuilles dans le couvert végétal. Ces spécificités sont associées à des variations de teneurs en glucides, d’acides aminés,de glucosinolates et de coumarines en lien étroit avec la régulation phytohormonale du développement foliaire et avec leur translocation dans le phloème. Le cas de la Proline a été plus particulièrement approfondi et l’activation de son catabolisme sous régulation circadienne dans les tissus sénescents a été mise en évidence. Une approche combinée de transcriptomique et de métabolomique a permis de démontrer une variabilité génotypique importante dans les processus de dégradation et de transport des protéines, glucides et acides aminés entre deux génotypes à forte ERA. De la même manière, des relatiOilseed rape is a very demanding oleaginous crop for nitrogen inputs associated with a low nitrogen use efficiency (NUE). The main challenge to improve the agri-environmental balance of oilseed rape is to optimize the NUE, especially under nitrogen deprivation. The NUE is limited by a low nitrogen remobilization efficiency (NRE) during leaf senescence. The aim of this thesis was to define the metabolome topology and orientation associated with NRE during leaf senescence in oilseed rape.The results show that leaf metabolome dynamically evolves throughout their vegetative growth, until their fall. Metabolome was found specific to each leaf rank, reflecting the trophic and environmental relationships related to the leaf positioning in the canopy. These specificities are associated with variations in carbohydrates, amino acids, glucosinolates and coumarins contents in close connection with the phytohormonal regulation of leaf development and with their translocation in the phloem.In particular, the activation of Proline circadian-controlled catabolism in senescent tissues was demonstrated. Finally, significant variations in the degradation and transport of proteins, carbohydrates and amino acids between two highly efficient NRE genotypes were highlighted using a combined transcriptomic and metabolomic approach. Similarly, a close relationship has been described between the genes expression levels and the metabolic content involved to increase NRE under low nitrogen input.The results are discussed regarding nitrogen remobilization improvement and more generally nutrients i
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Jones, Felicity Anne. "Growth and voluntary feed intake of two diverse genetic lines of pigs." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284424.
Full textBooks on the topic "Leaf dissection"
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Allen, Connie. Laboratory Manual for Anatomy and Physiology, 6e Loose-Leaf Print Companion and EPUB Reg Card & Cat Dissection: A Laboratory Guide, 3e Set. Wiley, 2018.
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Smith, Lori, and Elaine Marieb. Human Anatomy Laboratory Manual with Cat Dissections -- Loose Leaf. Pearson Education, 2022.
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Wiersinga, W. Joost, and Tom van der Poll. The host response to infection in the critically ill. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0303.
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Infection continues to be a leading cause of intensive care unit death. The host response to infection can be seen as a pattern recognition receptor (PRR)-mediated dysregulation of the immune system following pathogen invasion in which a careful balance between inflammatory and anti-inflammatory responses is vital. A measured and rapid response to microbial invasion is essential to health. The same immunological and coagulation systems that protect against localized infection can act to our disadvantage when these systems are activated systemically during generalized microbial infection. Toll-like receptors (TLR), the inflammasomes and other PRRs initiate the host response after recognition of pathogen-associated-molecular-patterns (PAMPs) or endogenous danger-associated-molecular-patterns (DAMPs). The systemic host response to infection will result in activation of coagulation, downregulation of physiological anticoagulant mechanisms, and inhibition of fibrinolysis. Further dissection of the role of host–pathogen interactions, the cytokine response, the coagulation cascade and their multidirectional interactions in sepsis should lead towards the development of new therapeutic approaches in the critically ill who are faced with infection.
Book chapters on the topic "Leaf dissection"
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Zaid, Waleed, Peter Park, Beomjune Kim, and Rob Laughlin. "Complications Related to Lymphatics and Chyle Leak." In Complications in Neck Dissection, 59–78. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-62739-3_4.
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Sebök, Martina, Jean-Philippe Dufour, Marco Cenzato, Yasuhiko Kaku, Michihiro Tanaka, Tetsuya Tsukahara, Luca Regli, and Giuseppe Esposito. "When Is Diagnostic Subtraction Angiography Indicated Before Clipping of Unruptured and Ruptured Intracranial Aneurysms? An International Survey of Current Practice." In Acta Neurochirurgica Supplement, 9–17. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-63453-7_2.
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AbstractIntroduction: The goal of this survey is to investigate the indications for preoperative digital subtraction angiography (DSA) before clipping of ruptured and unruptured intracranial aneurysms in an international panel of neurovascular specialists.Methods: An anonymous survey of 23 multiple-choice questions relating to indications for DSA before clipping of an intracranial aneurysm was distributed to the international panel of attendees of the European-Japanese Cerebrovascular Congress (EJCVC), which took place in Milan, Italy on 7–9 June 2018. The survey was collected during the same conference. Descriptive statistics were used to analyze the data.Results: A total of 93 surveys were distributed, and 67 (72%) completed surveys were returned by responders from 13 different countries. Eighty-five percent of all responders were neurosurgeons. For unruptured and ruptured middle cerebral artery (MCA) aneurysms without life-threatening hematoma, approximately 60% of responders perform surgery without preoperative DSA. For aneurysms in other locations than MCA, microsurgery is done without preoperative DSA in 68% of unruptured and in 73% of ruptured cases. In cases of ruptured MCA or ruptured non-MCA aneurysms with life-threatening hematoma, surgery is performed without DSA in 97% and 96% of patients, respectively. Factors which lead to preoperative DSA being performed were: aneurysmal shape (fusiform, dissecting), etiology (infectious), size (>25 mm), possible presence of perforators or efferent vessels arising from the aneurysm, intra-aneurysmal thrombus, previous treatment, location (posterior circulation and paraclinoid aneurysm) and flow-replacement bypass contemplated for final aneurysm treatment. These are all factors that qualify an aneurysm as a complex aneurysm.Conclusion: There is still a high variability in the surgeons’ preoperative workup regarding the indication for DSA before clipping of ruptured and unruptured intracranial aneurysms, except for ruptured aneurysms with life-threatening hematoma. There is a general consensus among cerebrovascular specialists that any angioanatomical feature indicating a complex aneurysm should lead to a more detailed workup including preoperative DSA.
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Gleissberg, Stefan. "Comparative developmental and molecular genetic aspects of leaf dissection." In Systematics Association Special Volumes, 404–17. CRC Press, 2002. http://dx.doi.org/10.1201/9781420024982.ch21.
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Sorajja, Paul. "Coronary Dissection From Paravalvular Leak Closure." In Structural Heart Cases, 156–57. Elsevier, 2019. http://dx.doi.org/10.1016/b978-0-323-54695-9.00077-9.
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Demaerschalk, Bart M. "Cervical Arterial Dissection." In Mayo Clinic Critical and Neurocritical Care Board Review, edited by Eelco F. M. Wijdicks, James Y. Findlay, William D. Freeman, and Ayan Sen, 600–602. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780190862923.003.0086.
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Cervical arterial dissections (CDs) are among the most common causes of stroke in young and middle-aged adults. CD is most prevalent in the upper cervical spine and may involve either the vertebral arteries or the carotid arteries. Mechanical forces can lead to intimal injuries of the cervical arteries and result in CD.
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Ferguson, Kris, and Alaa Abd-Elsayed. "Peripheral nerve stimulation trial and implantation." In Sacroiliac Joint Pain, edited by Alaa Abd-Elsayed and Dawood Sayed, 135–46. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780197607947.003.0013.
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This chapter will detail the surgical recommendations and step-by-step approaches for both trial stimulation and permanent implantation of peripheral nerve stimulation to treat sacroiliac joint pain. It also provides a brief history of this procedure, which has evolved from being a procedure that required careful, open dissection of the target nerve to a sleek treatment requiring only image guidance and a minimally invasive percutaneous approach. A trial stimulation period typically ranges from 7 to 14 days; steps for the trial simulation procedure include preparation, target point identification, and lead insertion. Additional topics for the permanent implantation procedure include tunneling and pocket dissection.
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Wellman, James K., Katie E. Corcoran, and Kate J. Stockly. "Dissecting Megachurch Scandals." In High on God, 189–214. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780199827718.003.0014.
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This chapter examines the dark side of megachurches by quantifying and theorizing megachurch scandals. We collected data on megachurch scandals and identified fifty-six such scandals discussed in forty-eight online newspaper articles for the years 2006 to 2017. Most of the scandals that we studied came from the malfeasance of megachurch senior pastors, and the vast majority were sexual in nature. The charismatic bond that megachurch pastors form with their attendees and the power that stems from it can be used for their own personal gain. We theorize a form of soft patriarchalism as a way to name this power differential. We contend that the model of soft patriarchalism gives power to men and creates opportunities for them to manipulate and ruin the lives of women under their care. These scandals often lead to the implosion of megachurches, where the charismatic bond between the pastor and congregation is irrevocably broken.
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Cooper, Kyle J., Constantino S. Peña, and James F. Benenati. "The Aorta." In Interventional Radiology, edited by Bradley B. Pua, Anne M. Covey, and David C. Madoff, 199–218. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190276249.003.0018.
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The aorta is the primary conduit delivering arterial blood from the heart to the rest of the body. Understanding its formation and development is essential to explaining its variant anatomy. The aorta can be involved in a large number of conditions. Atherosclerosis is the most common process that affects the aorta. In addition, acute aortic injury can lead to ulceration, dissection, rupture, and transection. Genetic and hereditable conditions involving the aorta are conditions that can cause a number of changes to the structural makeup of the aortic wall. Understanding these condition allows their proper recognition, diagnosis, and treatment. This chapter, therefore, will review the anatomy, pathophysiology, and disease management related to the aorta.
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Selden, Nathan R. "Genetic Epilepsy." In Functional Neurosurgery, C12—C12.P62. Oxford University PressNew York, 2019. http://dx.doi.org/10.1093/med/9780190887629.003.0012.
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Abstract Genetic epilepsies may present early in childhood with multiple seizure types, including tonic, atonic, and partial seizures. In patients refractory to management with anti-convulsant medications and/or ketogenic diet, as appropriate, and who do not have any imaging or electrophysiological evidence of focality, additional therapy may be undertaken using vagal nerve stimulation (VNS). The VNS lead is generally implanted in the mid-cervical region on the left (due to lesser effects on cardiac rhythm), with the generator placed in a subclavicular position. Like anti-convulsant drugs, VNS is palliative, and requires system upkeep, including but not limited to generator changes for battery life. Risks of VNS including treatment failure due to infection or device malfunction, hoarseness due to recurrent laryngeal nerve palsy, or rarely more serious surgical complications related to anterior neck dissection.
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Graddy, Ryan, and Darius A. Rastegar. "Stimulants." In ASAM Handbook of Addiction Medicine, 183–218. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780197506172.003.0008.
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Stimulants are sympathomimetic substances that include cocaine, amphetamines, and cathinones. Approximately 1% of Americans have used illicit stimulants in the past month, and nearly 25,000 deaths were attributed to stimulant overdose in 2017. Acute effects include tachycardia, elevated blood pressure, and euphoria. High doses of stimulants may lead to cardiac arrhythmias, severe hypertension, agitation, myocardial infarction, aortic dissection, stroke, hyperthermia, or rhabdomyolysis. Abstinence after regular use of stimulants may lead to dysphoria, fatigue, insomnia, and agitation. People who use stimulants may present with acute effects or medical complications. Cocaine metabolites and amphetamines can be detected in urine for a few days after use. The most serious complications of acute use are cardiovascular (especially myocardial infarction and stroke) and psychiatric (agitation and delirium); the risk of hyperthermia is also increased. A number of psychosocial modalities appear to reduce stimulant use among selected individuals, including individual and group counseling, cognitive–behavioral therapy, contingency management, and community reinforcement. No medication has been consistently shown to reduce complications and use of stimulants, although prescription stimulants and topiramate show some promise for treating cocaine use disorder. Syringe exchange programs and safe consumption sites are associated with decreased stimulant use-related complications. Caffeine has mild stimulant effects and may lead to a mild dependence syndrome.
Conference papers on the topic "Leaf dissection"
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Jou, Liang-Der, Deok Hee Lee, and Michel E. Mawad. "Arterial Flows in Carotid Artery Dissection." In ASME 2007 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2007. http://dx.doi.org/10.1115/sbc2007-176396.
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Dissection at the carotid artery is not infrequent, and it may lead to arterial stenosis, dissecting-aneurysm, ischemia stoke, or subarachnoid hemorrhage [2]. The exact cause of carotid artery dissection remains unknown, but it occurs often among young and middle-aged individuals who are otherwise healthy [3]. Extra-cranial carotid dissection is often managed conservatively by anti-thrombotic therapy, while the intracranial carotid dissection often requires interventional management.
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Alsager Alzayed, Mohammad, Christopher McComb, Samuel T. Hunter, and Scarlett R. Miller. "Helping Teams Expand the Breadth of Their Solution Space Through Product Dissection: A Simulation Based Investigation." In ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/detc2018-85832.
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Product dissection has been highlighted as an effective means of interacting with example products in order to produce creative outcomes. While product dissection is often conducted as a team in engineering design education as a component of larger engineering design projects, the research on the effectiveness of product dissection activities has been primarily limited to individuals. Thus, the goal of this study was to investigate the impact of the type(s) of product dissected in a team environment on the breadth of the design space explored and the underlying influence of educational level on these effects. This was accomplished through a computational simulation of 7,000 nominal brainstorming teams generated by a statistical bootstrapping technique that accounted for all possible team configurations. Specifically, each team was composed of four team members based on a design repository of 463 ideas generated by first-year and senior engineering design students after a product dissection activity. The results of the study highlight that simulated senior engineering design teams explored a larger solution space than simulated first-year teams and that dissecting different types of products allowed for the exploration of a larger solution space for all of the teams. The results also showed that dissecting two analogically far and two simple products was most effective in expanding the solution space for simulated senior teams. The findings presented in this study can lead to a better understanding of how to most effectively deploy product dissection modules in engineering design education in order to maximize the solution space explored.
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Starkey, Elizabeth M., Cailyn Spencer, Kevin Lesniak, Conrad Tucker, and Scarlett R. Miller. "Do Technological Advancements Lead to Learning Enhancements?: An Exploration in Virtual Product Dissection." In ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/detc2017-68237.
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Recent shifts into larger class sizes and online learning have caused engineering educators to rethink the way they integrate inductive, or active learning activities into their courses. One way engineering educators have done this is through the integration of new technological environments. However, little is known about how the type of technological environment utilized in active learning exercises impacts student learning and satisfaction. Thus, as a first step to understanding the impact of technological advancements on student learning and satisfaction, a study was conducted with 18 senior level undergraduate engineering students who were asked to perform product dissection, or the systematic disassembly of a product, using three technological interfaces (computer, iPad, immersive virtual reality). Variations in the complexity of the product dissected were also explored. The results of this study indicate that variations in technological interfaces did not impact student learning as assessed by a Student Learning Assessment (SLA). However, the complexity of the product dissected did impact learning, with students scoring significantly lower on the SLA when dissecting the most complex product. The results also indicated that students perceived learning and satisfaction were highest when using the immersive virtual reality system. These results suggest that the costs of investing in more technological advanced systems for product dissection may not yet outweigh the educational benefits. However, the increase in student satisfaction with VR environments has the potential to positively impact student retention in engineering programs.
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van Enschut, JFM (Hans) d'Achard. "Dissecting the creative leap." In Procedings of the Second Conference. New York, New York, USA: ACM Press, 2011. http://dx.doi.org/10.1145/2079216.2079239.
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Pasta, Salvatore, Julie A. Philippi, Thomas G. Gleason, and David A. Vorp. "Dissection Properties of Aneurysmal and Nonaneurysmal Human Ascending Thoracic Aorta: Preliminary Results." In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19520.
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Ascending thoracic aortic aneurysm (ATAA) is among the most devastating forms of cardiovascular disease, causing a significant mortality despite current medical and surgical treatments [1]. Moreover these therapies themselves are associated with great risk of mortality or morbidity, complicated by the advanced age of the typical patient, and high surgical costs. The mechanics of spontaneous aortic dissection is not fully understood. It is generally believed that aortic dissection initiates as an intimal tear in which a separation of wall layers produces the formation of a ‘false’ lumen. The dissection may propagate axially and/or circumferentially due to blood flow and pressure. Dissection may lead to several possible complications. For example, the septum between the false lumen and true lumen may fracture, resulting in embolism and ischemic damage. Another possibility is that the thinned and weakened residual outer aortic wall may fail, resulting in rapid blood loss and tamponade.
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Kelly, Brian P., John A. Glaser, and Denis J. DiAngelo. "Biomechancial Comparison of a Novel C1 Posterior Locking Plate With the Harms Technique in a C1-C2 Fixation Model." In ASME 2008 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2008. http://dx.doi.org/10.1115/sbc2008-193004.
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Current methods of atlantoaxial stabilization rely on screw fixation. Screw placement may be transarticular, or C1 lateral mass screws in combination with pedicle or pars screws at C2. These techniques can put the vertebral artery at risk. There is also dissection around the ganglion of the second cervical nerve root, which can lead to significant bleeding or postoperative pain.
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Pichamuthu, Joseph E., Julie A. Phillippi, Deborah A. Cleary, Douglas W. Chew, John Hempel, Thomas G. Gleason, and David A. Vorp. "Association of Mechanical Properties and Collagen Content With Valve Morphology in Ascending Thoracic Aortic Aneurysmal Tissue." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53873.
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Bicuspid aortic valve (BAV) is the most common congenital heart malformation occurring in 1–2% of the population with a high rate of morbidity [1]. There is a significantly higher rate of dilation of the aortic root in adults with a BAV when compared to the normal population and this condition is often associated with ascending thoracic aortic aneurysm (ATAA). ATAA is characterized as an enlargement of the aorta to twice its normal diameter. If left untreated, ATAA can lead to aortic dissection or rupture. Therefore, ATAA is recommended for prophylactic surgery when its diameter reaches about 5.5 cm. However, in certain high-risk cases, such as patients with BAV, ATAA may rupture when its diameter is less than 5.5 cm. Since ATAA dissection and rupture are biomechanical phenomena, better mechanical models are needed to more accurately predict these events over the predictive capability of diameter alone.
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Gotoh, Maya, Hisako Tokunaga, Kenji Kaneko, and Tsunenori Arai. "Air leak seal for lung dissection plane with diode laser irradiation: an ex vivo study." In Biomedical Optics (BiOS) 2007, edited by Steven L. Jacques and William P. Roach. SPIE, 2007. http://dx.doi.org/10.1117/12.701476.
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Gotoh, Maya, and Tsunenori Arai. "Air leak seal for lung dissection plane with diode laser irradiation: monitoring heat-denature with auto-fluorescence." In Biomedical Optics (BiOS) 2008, edited by Steven L. Jacques, William P. Roach, and Robert J. Thomas. SPIE, 2008. http://dx.doi.org/10.1117/12.764791.
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Beaton, Nigel, Jagat Adhikari, Yuehan Feng, Roland Bruderer, Ron Tomlinson, Ivan Cornella-Taracido, and Lukas Reiter. "Abstract 298: Dissection of drug-protein interactions by HR-LiP-MS in target validation and lead optimization." In Proceedings: AACR Annual Meeting 2021; April 10-15, 2021 and May 17-21, 2021; Philadelphia, PA. American Association for Cancer Research, 2021. http://dx.doi.org/10.1158/1538-7445.am2021-298.
Full textReports on the topic "Leaf dissection"
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Ghanim, Murad, Joe Cicero, Judith K. Brown, and Henryk Czosnek. Dissection of Whitefly-geminivirus Interactions at the Transcriptomic, Proteomic and Cellular Levels. United States Department of Agriculture, February 2010. http://dx.doi.org/10.32747/2010.7592654.bard.
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Our project focuses on gene expression and proteomics of the whitefly Bemisia tabaci (Gennadius) species complex in relation to the internal anatomy and localization of expressed genes and virions in the whitefly vector, which poses a major constraint to vegetable and fiber production in Israel and the USA. While many biological parameters are known for begomovirus transmission, nothing is known about vector proteins involved in the specific interactions between begomoviruses and their whitefly vectors. Identifying such proteins is expected to lead to the design of novel control methods that interfere with whitefly-mediated begomovirus transmission. The project objectives were to: 1) Perform gene expression analyses using microarrays to study the response of whiteflies (B, Q and A biotypes) to the acquisition of begomoviruses (Tomato yellow leaf curl (TYLCV) and Squash leaf curl (SLCV). 2) Construct a whitefly proteome from whole whiteflies and dissected organs after begomovirus acquisition. 3) Validate gene expression by q-RTPCR and sub-cellular localization of candidate ESTs identified in microarray and proteomic analyses. 4) Verify functionality of candidate ESTs using an RNAi approach, and to link these datasets to overall functional whitefly anatomical studies. During the first and second years biological experiments with TYLCV and SLCV acquisition and transmission were completed to verify the suitable parameters for sample collection for microarray experiments. The parameters were generally found to be similar to previously published results by our groups and others. Samples from whole whiteflies and midguts of the B, A and Q biotypes that acquired TYLCV and SLCV were collected in both the US and Israel and hybridized to B. tabaci microarray. The data we analyzed, candidate genes that respond to both viruses in the three tested biotypes were identified and their expression that included quantitative real-time PCR and co-localization was verified for HSP70 by the Israeli group. In addition, experiments were undertaken to employ in situ hybridization to localize several candidate genes (in progress) using an oligonucleotide probe to the primary endosymbiont as a positive control. A proteome and corresponding transcriptome to enable more effective protein identification of adult whiteflies was constructed by the US group. Further validation of the transmission route of begomoviruses, mainly SLCV and the involvement of the digestive and salivary systems was investigated (Cicero and Brown). Due to time and budget constraints the RNAi-mediated silencing objective to verify gene function was not accomplished as anticipated. HSP70, a strong candidate protein that showed over-expression after TYLCV and SLCV acquisition and retention by B. tabaci, and co-localization with TYLCV in the midgut, was further studies. Besides this protein, our joint research resulted in the identification of many intriguing candidate genes and proteins that will be followed up by additional experiments during our future research. To identify these proteins it was necessary to increase the number and breadth of whitefly ESTs substantially and so whitefly cDNAs from various libraries made during the project were sequenced (Sanger, 454). As a result, the proteome annotation (ID) was far more successful than in the initial attempt to identify proteins using Uniprot or translated insect ESTs from public databases. The extent of homology shared by insects in different orders was surprisingly low, underscoring the imperative need for genome and transcriptome sequencing of homopteran insects. Having increased the number of EST from the original usable 5500 generated several years ago to >600,000 (this project+NCBI data mining), we have identified about one fifth of the whitefly proteome using these new resources. Also we have created a database that links all identified whitefly proteins to the PAVEdb-ESTs in the database, resulting in a useful dataset to which additional ESTS will be added. We are optimistic about the prospect of linking the proteome ID results to the transcriptome database to enable our own and other labs the opportunity to functionally annotate not only genes and proteins involved in our area of interest (whitefly mediated transmission) but for the plethora of other functionalities that will emerge from mining and functionally annotating other key genes and gene families in whitefly metabolism, development, among others. This joint grant has resulted in the identification of numerous candidate proteins involved in begomovirus transmission by B. tabaci. A next major step will be to capitalize on validated genes/proteins to develop approaches to interfere with the virus transmission.
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Levin, Ilan, John Thomas, Moshe Lapidot, Desmond McGrath, and Denis Persley. Resistance to Tomato yellow leaf curl virus (TYLCV) in tomato: molecular mapping and introgression of resistance to Australian genotypes. United States Department of Agriculture, October 2010. http://dx.doi.org/10.32747/2010.7613888.bard.
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Tomato yellow leaf curl virus (TYLCV) is one of the most devastating viruses of cultivated tomatoes. Although first identified in the Mediterranean region, it is now distributed world-wide. Sequence analysis of the virus by the Australian group has shown that the virus is now present in Australia. Despite the importance of the disease and extensive research on the virus, very little is known about the resistance genes (loci) that determine host resistance and susceptibility to the virus. A symptom-less resistant line, TY-172, was developed at the Volcani Center which has shown the highest resistance level among all tested varieties. Preliminary results show that TY-172 is a good candidate to confer resistance to both TYLCV and to Tomato leaf curl virus (ToLCV) in Queensland conditions. Furthermore, Segregation analysis has previously indicated that the resistance is determined by 2-3 genes. In this proposal we aimed to substantiate that TY-172 can contribute to resistance breeding against TYLCV in Queensland, to develop DNA markers to advance such resistance breeding in both Israel and Queensland, and to exploit these markers for resistant breeding in Australian and Israeli lines. To map quantitative trait loci (QTLs) controlling TYLCVresistance in TY172, appropriate segregating populations were analyzed using 69 polymorphic DNA markers spanning the entire tomato genome. Results show that TYLCV resistance in TY172 is controlled by a previously unknown major QTL, originating from the resistant line, and four additional minor QTLs. The major QTL, termed Ty-5, maps to chromosome 4 and accounts for 39.7-to-46.6% of the variation in symptom severity among segregating plants (LOD score: 33-to-35). The minor QTLs, originated either from the resistant or susceptible parents, were mapped to chromosomes 1, 7, 9 and 11, and contributed 12% to the variation in symptom severity in addition to Ty-5. Further analysis of parental lines as well as large F₁, BC₁F₁, F₂ and BC₁F₂ populations originating from crosses carried out, in reciprocal manner, between TY172 and the susceptible processing line M-82 (LA3475) during spring-summer 2010, indicated that: (1) the minor QTLs we have previously identified are in effect not reproducible, (2)Ty-5 alone can yield highly resistant plants with practically no extra-chromosomal effects, and (3) the narrow-sense heritability estimate of resistance levels, attributed to additive factors responsive to selection, does not significantly deviate from 1. All of these results point to Ty-5 as the sole resistance locus in TY172 thus significantly increasing the likelihood of its successful molecular dissection. The DNA markers developed during the course of this study were transferred together with the TY172 genotype to Queensland. TY172 was crossed to a panel of Australian genotypes and the resulting populations were subjected to segregation analysis. Results showed that resistant locus, Ty-5, is highly reproducible in the Australian conditions as well. The Australian group was also able to make improvements to the marker assays by re-designing primer pairs to provide more robust PCR fragments. The Ty-5 locus has now been introgressed into elite Australian germplasm and selection for TYLCV resistance has begun. Cumulatively, our results show that Ty-5 can be effectively used, together with the TY172 genotype to expedite TYLCV resistance breeding and improve our understanding of the genetics that underline the response of tomato to TYLCV. Contributions to agriculture include: (1) the development of tools for more efficient resistance breeding, allowing the incorporation of resistance to local tomato varieties in Australia, Israel and elsewhere; and (2) establish a solid framework for a future attempt to clone the genes that encode such resistance. The latter will enable to decipher the resistance mechanisms that could be applied to other geminiviruses in tomato and possibly in other plant species.
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Antignus, Yehezkiel, Ernest Hiebert, Shlomo Cohen, and Susan Webb. Approaches for Studying the Interaction of Geminiviruses with Their Whitefly Vector Bemisia tabaci. United States Department of Agriculture, July 1995. http://dx.doi.org/10.32747/1995.7604928.bard.
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The DNA of tomato yellow leaf curl virus (TYLCB) was detected in its whitefly vector, Bemisia tabaci, by dot spot hybridization as early as 1 h after acquisition access. The retention of the virus nucleic acid in the vector was at least 23 days after a 48 h acquisition access. However, the retention of TYLCV coat protein did not exceed 10 days. No replicative forms of TYLCV could be detected in B. tabaci, indicating a non-propagative relationship with the vector. Whiteflies were not able to accumulate naked virion ssDNA, virus cloned dsDNA, or virions with impaired coat protein. Deletion, frameshift, and single amino acid mutations were inserted into open reading frames (ORFs) V1 and V2 (Coat protein) of TYLCV. The ability of these mutants to replicate, to spread and to induce symptoms was tested both in leaf disks and in intact plants. No replication was found in tissues that were infected with a deletion mutant that lacked the carboxy half of the coat protein gene. Residual amounts of ssDNA and dsDNA were detected i tissues infected with a frameshift mutant in which an early termination at the extreme part of the protein. Two other mutants in which a single amino acid was changed in the overlapping part of V1 and V2 were able to spread systemically but infections remained symptomless and the production of ssDNA and dsDNA were significantly lower. These mutants were acquired and transmitted by Bemisia tabaci. Procedures for the the dissection, fixation and embedding of whiteflies were developed. The anatomy and ultrastructure of the salivary gland and the midgut of Bemisia tabaci and Trialeurodes vaporariorum (a vector and non-vector of geminiviruses respectively) was studied and described. Monoclonal antibodies against bean golden mosaic virus (BGMV) with narrow and broad spectrum were prepared. Transmission studies of tomato mottle geminivirus (TMoV) by B. tabaci were carried out. These studies were essential for a further work aimed to understand the interaction of geminiviruses with the insect and their localization in its tissues. To enable the production of transgenic plants procedures were developed for tomato transformation with both Agrobacterium and microparticle bombardment.
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Fridman, Eyal, Jianming Yu, and Rivka Elbaum. Combining diversity within Sorghum bicolor for genomic and fine mapping of intra-allelic interactions underlying heterosis. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597925.bard.
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Heterosis, the enigmatic phenomenon in which whole genome heterozygous hybrids demonstrate superior fitness compared to their homozygous parents, is the main cornerstone of modern crop plant breeding. One explanation for this non-additive inheritance of hybrids is interaction of alleles within the same locus. This proposal aims at screening, identifying and investigating heterosis trait loci (HTL) for different yield traits by implementing a novel integrated mapping approach in Sorghum bicolor as a model for other crop plants. Originally, the general goal of this research was to perform a genetic dissection of heterosis in a diallel built from a set of Sorghum bicolor inbred lines. This was conducted by implementing a novel computational algorithm which aims at associating between specific heterozygosity found among hybrids with heterotic variation for different agronomic traits. The initial goals of the research are: (i) Perform genotype by sequencing (GBS) of the founder lines (ii) To evaluate the heterotic variation found in the diallel by performing field trails and measurements in the field (iii) To perform QTL analysis for identifying heterotic trait loci (HTL) (iv) to validate candidate HTL by testing the quantitative mode of inheritance in F2 populations, and (v) To identify candidate HTL in NAM founder lines and fine map these loci by test-cross selected RIL derived from these founders. The genetic mapping was initially achieved with app. 100 SSR markers, and later the founder lines were genotyped by sequencing. In addition to the original proposed research we have added two additional populations that were utilized to further develop the HTL mapping approach; (1) A diallel of budding yeast (Saccharomyces cerevisiae) that was tested for heterosis of doubling time, and (2) a recombinant inbred line population of Sorghum bicolor that allowed testing in the field and in more depth the contribution of heterosis to plant height, as well as to achieve novel simulation for predicting dominant and additive effects in tightly linked loci on pseudooverdominance. There are several conclusions relevant to crop plants in general and to sorghum breeding and biology in particular: (i) heterosis for reproductive (1), vegetative (2) and metabolic phenotypes is predominantly achieved via dominance complementation. (ii) most loci that seems to be inherited as overdominant are in fact achieving superior phenotype of the heterozygous due to linkage in repulsion, namely by pseudooverdominant mechanism. Our computer simulations show that such repulsion linkage could influence QTL detection and estimation of effect in segregating populations. (iii) A new height QTL (qHT7.1) was identified near the genomic region harboring the known auxin transporter Dw3 in sorghum, and its genetic dissection in RIL population demonstrated that it affects both the upper and lower parts of the plant, whereas Dw3 affects only the part below the flag leaf. (iv) HTL mapping for grain nitrogen content in sorghum grains has identified several candidate genes that regulate this trait, including several putative nitrate transporters and a transcription factor belonging to the no-apical meristem (NAC)-like large gene family. This activity was combined with another BARD-funded project in which several de-novo mutants in this gene were identified for functional analysis.
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Lifschitz, Eliezer, and Elliot Meyerowitz. The Relations between Cell Division and Cell Type Specification in Floral and Vegetative Meristems of Tomato and Arabidopsis. United States Department of Agriculture, February 1996. http://dx.doi.org/10.32747/1996.7613032.bard.
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Meristems were the central issue of our project. Genes that are required for cell division, cell elongation, cell proliferation and cell fate were studied in the tomato system. The analysis of the dUTPase and threonine deaminase genes, along with the dissection of their regulatory regions is completed, while that of the RNR2 and PPO genes is at an advanced stage. All these genes were isolated in our laboratory. In addition, 8 different MADS box genes were studied in transgenic plants and their genetic relevances discovered. We have also shown that a given MADS box gene can modify the polarity of cell division without affecting the fate of the organ. In vivo interaction between two MADS box genes was demonstrated and the functional dependency of the tomato agamous gene on the TM5 gene product established. We have exploited the Knotted1 meristematic gene in conjunction with tomato leaf meristematic genes to show that simple and compound leaves and, for that matter, sepals and compound leaves, are formed by two different developmental programs. In this context we have also isolated and characterized the tomato Knotted1 gene (TKnl) and studied its expression pattern. A new program in which eight different meristematic genes in tomato will be studied emerged as a result of these studies. In essence, we have shown that it is possible to study and manipulate plant developmental systems using reverse genetic techniques and have provided a wealth of new molecular tools to interested colleagues working with tomato. Similarly, genes responsible for cell division, cell proliferation and cell fate were studied in Arabidopsis floral meristems. Among these genes are the TSO1, TSO2, HANABA TARANU and UNUSUAL FLORAL ORGANS genes, each affecting in its own way the number of pattern of cell divisions, and cell fate, in developing Arabodopsis flowers. In addition, new methods have been established for the assessment of the function of regulatory gene action in the different clonal layers of developing floral meristems.
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Fridman, Eyal, and Eran Pichersky. Tomato Natural Insecticides: Elucidation of the Complex Pathway of Methylketone Biosynthesis. United States Department of Agriculture, December 2009. http://dx.doi.org/10.32747/2009.7696543.bard.
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Plant species synthesize a multitude of specialized compounds 10 help ward off pests. and these in turn may well serve as an alternative to synthetic pesticides to reduce environmental damage and health risks to humans. The general goal of this research was to perform a genetic and biochemical dissection of the natural-insecticides methylketone pathway that is specific to the glandular trichomes of the wild species of tomato, Solanumhabrochaites f. glabratum (accession PI126449). Previous study conducted by us have demonstrated that these compounds are synthesized de novo as a derivate pathway of the fatty acid biosynthesis, and that a key enzyme. designated MethylketoneSynthase 1 (MKS 1). catalyzes conversion of the intermediate B-ketoacyl- ACPs to the corresponding Cn-1 methylketones. The approach taken in this proposed project was to use an interspecific F2 population. derived from the cross between the cultivated lV182 and the wild species PIl26449. for three objectives: (i) Analyze the association between allelic status of candidate genes from the fatty acid biosynthesis pathway with the methylketone content in the leaves (ii) Perform bulk segregant analysis of genetic markers along the tomato genome for identifying genomic regions that harbor QTLs for 2TD content (iii) Apply differential gene expression analysis using the isolated glands of bulk segregant for identifying new genes that are involved in the pathway. The genetic mapping in the interspecific F2 population included app. 60 genetic markers, including the candidate genes from the FAS pathway and SSR markers spread evenly across the genome. This initial; screening identified 5 loci associated with MK content including the candidate genes MKS1, ACC and MaCoA:ACP trans. Interesting observation in this genetic analysis was the connection between shape and content of the glands, i.e. the globularity of the four cells, typical to the wild species. was associated with increased MK in the segregating population. In the next step of the research transcriptomic analysis of trichomes from high- and 10w-MK plants was conducted. This analysis identified a new gene, Methy1ketone synthase 2 (MKS2), whose protein product share sequence similarity to the thioesterase super family of hot-dog enzymes. Genetic analysis in the segregating population confirmed its association with MK content, as well as its overexpression in E. coli that led to formation of MK in the media. There are several conclusions drawn from this research project: (i) the genetic control of MK accumulation in the trichomes is composed of biochemical components in the FAS pathway and its vicinity (MKS 1 and MKS2). as well as genetic factors that mediate the morphology of these specialized cells. (ii) the biochemical pathway is now realized different from what was hypothesized before with MKS2 working upstream to I\1KS 1 and serves as the interface between primary (fatty acids) and secondary (MK) metabolism. We are currently testing the possible physical interactions between these two proteins in vitro after the genetic analysis showed clear epistatic interactions. (iii) the regulation of the pathway that lead to specialized metabolism in the wild species is largely mediated by transcription and one of the achievements of this project is that we were able to isolate and verify the specificity of the MKS1 promoter to the trichomes which allows manipulation of the pathways in these cells (currently in progress). The scientific implications of this research project is the advancement in our knowledge of hitherto unknown biochemical pathway in plants and new leads for studying a new family in plants (hot dog thioesterase). The agricultural and biotechnological implication are : (i) generation of new genetic markers that could assist in importing this pathway to cultivated tomato hence enhancing its natural resistance to insecticides, (ii) the discovery of MKS2 adds a new gene for genetic engineering of plants for making new fatty acid derived compounds. This could be assisted with the use of the isolated and verified MKS1 promoter. The results of this research were summarized to a manuscript that was published in Plant Physiology (cover paper). to a chapter in a proceeding book. and one patent was submitted in the US.