3 resultados para HAL

em Brock University, Canada


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Ultrasonic vocalizations (USV) are emitted by rats in a number of social situations such as aggressive encounters, during sexual behavior, and during play in young rats, situations which are predominantly associated with strong emotional responses. These USV typically involve two distinct types of calls: 22 kHz calls, which are emitted in aversive situations and 50 kHz calls, which are emitted in non-aversive, appetitive situation. The 50 kHz calls are the focus of the present study and to date both the glutamatergic and the dopaminergic systems have been independently implicated in the production of these 50 kHz calls. The present study was conducted to examine a possible relationship between glutamate (GLU) and dopamine (DA) in mediating 50 kHz calls. It was hypothesized that the dopaminergic system plays a mediating role in 50 kHz calls induced by injections ofGLU into the anterior hypothalamic/preoptic area (AHPOA) in adult rats. A total of 68 adult male rats were used in this study. Rats' USV were recorded and analyzed in five experiments that were designed to test the hypothesis: in experiment 1, rats were treated with systemic amphetamine (AMPH) alone; in experiment 2, intra- AHPOA GLU was pretreated with systemic AMPH; in experiment 3, intra-AHPOA GLU was pretreated with intra-AHPOA AMPH; in experiment 4, rats were treated with high and low doses of intra-AHPOA AMPH only; in experiment 5, rats were treated with systemic haloperidol (HAL) as a pretreatment for intra-AHPOA GLU. Analysis of the results indicated that AMPH has a facilitatory effect on 50 kHz USV and that a relationship between DA and GLU in inducing 50 kHz calls does exist. The effect, however, was only observed when DA receptors were antagonized with HAL and was not seen with systemic AMPH pretreatments of intra-AHPOA GLU. The DAGLU relationship at the AHPOA was unclear.

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This work consists of a theoretical part and an experimental one. The first part provides a simple treatment of the celebrated von Neumann minimax theorem as formulated by Nikaid6 and Sion. It also discusses its relationships with fundamental theorems of convex analysis. The second part is about externality in sponsored search auctions. It shows that in these auctions, advertisers have externality effects on each other which influence their bidding behavior. It proposes Hal R.Varian model and shows how adding externality to this model will affect its properties. In order to have a better understanding of the interaction among advertisers in on-line auctions, it studies the structure of the Google advertisements networ.k and shows that it is a small-world scale-free network.

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The National Seaman’s Association was a labour recruiter hiding behind a union-like name. It was run by H.N. McMaster who collected fees from companies and dues from workers. With McMaster in charge, shipping interests could claim that their seamen had a union, but ship-owners were free to push their vessels and their workers to the breaking point. In 1935, the members on the Great Lakes decided to strike. One year later, they created their own union and amalgamated with a Montreal-based independent body to create the Canadian Seamen’s Union headed by a ship’s cook who became a union leader, John Allan Patrick “Pat” Sullivan. By the late 1940s, almost all sailors on Canadian ships were CSU members. Right from its inception in 1936, Communists were prominent among the leaders of the union. Sullivan had been recruited to the Communist party that year and the union had a close rapport with the party. On June 8, 1940, Pat Sullivan was arrested because of his affiliation with the Communist party. He was incarcerated until March 20, 1942. No charges were laid, no bail was set and there was no trial. After his release, Sullivan was elected second vice-president of the Trades and Labour Congress of Canada. In 1943, Percy Bengough was elected as president and Sullivan was elected as secretary treasurer of the TLC while maintaining his role as president of the CSU. On March 14, 1947 Sullivan made a shocking announcement that he was resigning from the CSU and the Labor-Progressive Party. He claimed that the CSU was under the full control of the Communists. Within a month of this announcement, he emerged as the president of the Canadian Lake Seamen’s Union. Ship-owners never really reconciled themselves to having their industry unionized, and in 1946 there was a seamen’s strike in which the union won the eight-hour day. In 1949, the shipping companies had a plan to get rid of the union and were negotiating behind their back with the Seafarers International Union (SIU). In a brutal confrontation, led by Hal Banks, an American ex-convict, the SIU was able to roust the CSU and take over the bargaining rights of Canadian seamen. On July 15, 1948, Robert Lindsay, who was Sullivan’s Welland business agent said that to the best of his knowledge, Sullivan’s outfit, the CLSU, was under the control of some of the Steamship Companies. Lindsay had heard that there was a movement to get rid of Bengough of the Trades and Labour Congress as well as elements of the CSU. He also had heard that the CLSU wanted to affiliate with the American Federation of Labor. Lindsay’s allegations raised the questions: Were the ship-owners powerful enough to oust Percy Bengough because he supported the seamen? Could the CLSU get an affiliation with the American Federation of Labor? and Would the American Federation of Labor actually affiliate with a union that was siding with employers against a locked-out union?