12 resultados para defence

em Brock University, Canada


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Trichoderma spp are effective competitors against other fungi because they are mycoparasitic and produce hydrolytic enzymes and secondary metabolites that inhibit the growth of their competitors. Inhibitory compounds produced by Trichoderma aggressivum, the causative agent of green mold disease, are more toxic to the hybrid off-white strains of Agaricus bisporus than the commercial brown strains, consistent with the commercial brown strain’s increased resistance to the disease. This project looked at the response of hybrid off-white and commercial brown strains of A. bisporus to the presence of T. aggressivum metabolites with regard to three A. bisporus genes: laccase 1, laccase 2, and manganese peroxidase. The addition of T. aggressivum toxic metabolites had no significant effect on MnP or lcc1 transcript abundance. Alternatively, laccase 2 appears to be involved in resistance to T. aggressivum because the presence of T. aggressivum metabolites results in higher lcc2 transcript abundance and laccase activity, especially in the commercial brown strain. The difference in laccase expression and activity between A. bisporus strains was not a result of regulatory or coding sequence differences. Alteration of laccase transcription by RNAi resulted in transformants with variable levels of laccase transcript abundance. Transformants with a low number of lcc transcripts were very sensitive to T. aggressivum toxins, while those with a high number of lcc transcripts had increased resistance. These results indicated that laccase activity, in particular that encoded by lcc2, serves as a defense response of A. bisporus to T. aggressivum toxins and contributes to green mold disease resistance in commercial brown strains.

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Large carpenter bees (Hymenoptera: Apidae: Xylocopa) have traditionally been thought of as exhibiting solitary or occasionally communal colony social organization. However, studies have demonstrated more complex fonns of social behaviour in this genus. In this document, I examine elements ofbehaviour and life history in a North American species at the northern extreme of its range. Xylocopa virginica was found to be socially polymorphic with both solitary and meta-social or semi-social nests in the same population. In social nests, there is no apparent benefit from additional females which do not perfonn significant work or guarding. I found that the timing of life-history events varies between years, yet foraging effort only differed in the coldest and wettest year of2004 the study. Finally, I that male X virginica exhibit female defence polygyny, with resident and satellite males. Resident males maintain their territories through greater aggression relative to satellites.

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There has been considerable debate over whether corporal punishment against children should be prohibited in Canada. Various organizations, most notably the Canadian Foundation for Children, Youth and the Law, have argued that the Canadian Government should ban the use of corporal punishment by repealing the specific section of the Canadian Criminal Code that provides parents with a legal defence to use corporal punishment against their children; this provision is outlined in Section 43 of the Criminal Code. Recently, the Canadian Foundation for Children, Youth and the Law challenged the constitutionality of Section 43 before the Supreme Court of Canada. The organization claimed Section 43 is unconstitutional. It violates children's Charter rights, such as the right to security of a person (Section 7), the right to be protected from cruel and unusual treatment (Section 12), and denies children the same protection adults receive under the law. Both the Canadian government and the Supreme Court of Canada reject the Foundation's arguments. Examining the federal government and the judicial system's rationale for refusing to remove Section 43 of the Canadian Criminal Code discloses how the parent-child relationship is perceived. This thesis examines how the parent-child relationship is perceived by the Canadian government and the issues that arise from such a view. This examination is essential for the comprehension of why Canada's corporal punishment law was enacted and remains in effect today.

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This daily paper, except Sundays, began publication on August 17, 1813 and ceased April 30, 1817. It was also published tri-weekly for a "COUNTRY" edition. The paper later became the Baltimore Patriot. Topics of interest include: Page 1: announcement Capt. M. Simmones Burnbury is seeking men to form a company of Sea Fencibles; Page 2: U.S. Legislature authorizes bill to increase the Marine Corps; U.S. Legislature authorizes bill to purchase vessels captured on Lake Erie; U.S. Senate bill authorizes the appointment of officers for the flotilla service; President of United States authorized to accept service of volunteer corps for defence of United States; Letter from Capt. A. H. Holmes to Lieut. Col. Butler detailing an American victory over the British near Detroit; announcement of British forces building barges for the purpose of attacking Detroit; War sloop Erie returns to Baltimore unable to reach sea due to British forces in the Chesapeake; Page 3: Death notice of Mr. Ward Fairchild of the U.S. Army; Page 4: Commander of the U.S. Flotilla seeks men for the Chesapeake Flotilla.

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Full Title: Speech of the Hon. Daniel Sheffey : on the Bill "to authorise the President of the United States to call upon the several States and Territories thereof for their respective quotas of eighty thousand men for the defence of the frontiers of the United States against invasion", delivered in the House of Representatives of the United States, on the tenth day of December, 1814 Printed by Rapine and Elliot

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H.A.S. (Henry Alexander Scammell) Dearborn (1783-1851) was the son of Henry Dearborn, the American politician and veteran of the Revolutionary War and War of 1812. In the War of 1812, H.A.S Dearborn served as Brigadier General of the volunteer forces, responsible for the defence of Boston Harbour. From 1812-1829 he was collector of customs in Boston, from 1831-1833 he served as a representative from Massachusetts in the United States Congress, was adjutant general of Massachusetts from 1834-1843 and mayor of Roxbury from 1847-1851. Letter transcription: Dear Sir, My success in the line of recruiting has exceeded my most sanguine expectations. I have enlisted 24 1st Lt. 30—my 2nd Lt. 13, and my Ensign 9—Total 76. All very [ablebodied] men. In all probability my company will be full before the last day of June. I shall be in Boston on the 10th of June. I have not yet had the pleasure to hear of the arrival of your father at Boston. Please to offer my respects to your family, and to all my friends in the [office]. In haste, Yours, A.M. Clary.

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A certificate of service from the Canadian Army for Lt. Col. Frank Edward McCordick. The document describes where he served (United Kingdom, Central Mediterranean, Continental Europe) and the length of his service (1939-1945). Included on the certificate is a list of medals/decorations which include: 1939-45 Star, Italy Star, France and Germany Star, Defence Medal Canadian Volunteer Service Medal and Clasp.

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During infection, the model plant Arabidopsis thaliana is capable of activating long lasting defence responses both in tissue directly affected by the pathogen and in more distal tissue. Systemic acquired resistance (SAR) is a type of systemic defence response deployed against biotrophic pathogens resulting in altered plant gene expression and production of antimicrobial compounds. One such gene involved in plant defence is called pathogenesis-related 1 (PR1) and is under the control of several protein regulators. TGA II-clade transcription factors (namely TGA2) repress PR1 activity prior to infection by forming large oligomeric complexes effectively blocking gene transcription. After pathogen detection, these complexes are dispersed by a mechanism unknown until now and free TGA molecules interact with the non-expressor of pathogenesis-related gene 1 (NPR1) protein forming an activating complex enabling PR1 transcription. This study elucidates the TGA2 dissociation mechanism by introducing protein kinase CK2 into this process. This enzyme efficiently phosphorylates TGA2 resulting in two crucial events. Firstly, the DNA-binding ability of this transcription factor is completely abolished explaining how the large TGA2 complexes are quickly evicted from the PR1 promoter. Secondly, a portion of TGA2 molecules dissociate from the complexes after phosphorylation which likely makes them available for the formation of the TGA2-NPR1 activating complex. We also show that phosphorylation of a multiserine motif found within TGA2’s N terminus is responsible for the change of affinity to DNA, while modification of a single threonine in the leucine zipper domain seems to be responsible for deoligomerization. Despite the substantial changes caused by phosphorylation, TGA2 is still capable of interacting with NPR1 and these proteins together form a complex on DNA promoting PR1 transcription. Therefore, we propose a change in the current model of how PR1 is regulated by adding CK2 which targets TGA2 displacing it’s complexes from the promoter and providing solitary TGA2 molecules for assembly of the activating complex. Amino acid sequences of regions targeted by CK2 in Arabidopsis TGA2 are similar to those found in TGA2 homologs in rice and tobacco. Therefore, the molecular mechanism that we have identified may be conserved among various plants, including important crop species, adding to the significance of our findings.