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Eadie–Hofstee diagram

In biochemistry, an Eadie–Hofstee diagram is a graphical representation of enzyme kinetics. In the diagram the reaction rate is plotted as a function of the ratio between rate and substrate concentration: v = − K M v + V max where v represents reaction rate, KM is the Michaelis–Menten constant, is the substrate concentration, Vmax is the maximum reaction rate, it can be derived from the Michaelis–Menten equation as follows: v = V max K M + invert and multiply with V max: V max v = V max V max = K M + Rearrange: V max = v K M + v = v K M + v Isolate v: v = − K M v + V max A plot of v against v/ will hence yield Vmax as the y-intercept, Vmax/KM as the x-intercept, KM as the negative slope. Like other techniques that linearize the Michaelis–Menten equation, the Eadie–Hofstee plot was used for rapid identification of important kinetic terms like KM and Vmax, but has been superseded by nonlinear regression methods that are more accurate and no longer computationally inaccessible, it is more robust against error-prone data than the Lineweaver–Burk plot because it gives equal weight to data points in any range of substrate concentration or reaction rate.

Both plots remain useful as a means to present data graphically. One drawback from the Eadie–Hofstee approach is that neither ordinate nor abscissa represent independent variables: both are dependent on reaction rate, thus any experimental error will be present in both axes. Experimental error or uncertainty will propagate unevenly and become larger over the abscissa thereby giving more weight to smaller values of v/. Therefore, the typical measure of goodness of fit for linear regression, the correlation coefficient R, is not applicable. Michaelis–Menten equation Lineweaver–Burk plot Hanes–Woolf plot Eadie, GS. "The Inhibition of Cholinesterase by Physostigmine and Prostigmine". Journal of Biological Chemistry. 146: 85–93. Hofstee, BHJ. "Non-Inverted Versus Inverted Plots in Enzyme Kinetics". Nature. 184: 1296–1298. Doi:10.1038/1841296b0. PMID 14402470. Dowd, JE. "A Comparison of Estimates of Michaelis–Menten Kinetic Constants from Various Linear Transformations". Journal of Biological Chemistry. 240: 863–869.

PMID 14275146. Atkins, GL. "A comparison of seven methods for fitting the Michaelis–Menten equation". Biochemical Journal. 149: 775–777. PMC 1165686. PMID 1201002

2009 Catalunya GP2 Series round

The 2009 Spanish GP2 round was a GP2 Series motor race held on May 9 and May 10, 2009 at the Circuit de Catalunya in Montmeló, Spain. It was the first race of the 2009 GP2 Season; the race was used to support the 2009 Spanish Grand Prix The first race resulted in a one-two finish for Barwa Addax Team drivers Romain Grosjean and Vitaly Petrov, with Jérôme d'Ambrosio finishing third for DAMS. The second race was won by Edoardo Mortara for Telmex Arden International, with Romain Grosjean and Jérôme d'Ambrosio on the podium. Mortara finished sixth in his first race, so was automatically on Pole for race 2, he wins in his first GP2 Weekend. Notes ^ – Luca Filippi was handed a 3-place grid penalty for failing to sufficiently heed yellow flags during free practice. ^ – Javier Villa was handed a 3-place grid penalty for failing to sufficiently heed yellow flags during free practice. Note: Only the top five positions are included for both sets of standings. Http://www.autosport.com/news/report.php/id/75190 https://web.archive.org/web/20090517084521/http://www.gp2series.com/en/website/2009gp2series/news/newsgp2/newsdetail.php?articleid=2309 https://web.archive.org/web/20120929185910/http://www.f1sa.com/index.php?option=com_content&view=article&id=13231:gp2--2009-spain-qualifying-report-a-results-romain-grosjean-storms-to-pole&catid=18:gp2&Itemid=132

Paul Kelly (lawyer)

Not to be confused with Paul V. Kelly. Paul V. Kelly is a prominent Massachusetts-based American lawyer and the former executive director of the National Hockey League Players' Association from October 24, 2007, to August 31, 2009, former executive director of College Hockey, Inc. Kelly is a partner in the Boston office of Jackson Lewis P. C. and is chair of the White Collar & Government Enforcement practice group and co-chair of the Collegiate & Professional Sports Industry practice group. Kelly founded the Boston-based law firm Kelly and Hoopes. Kelly was the assistant United States attorney during the trial and investigation of then-NHLPA head Alan Eagleson over corruption and embezzlement. Eagleson pleaded guilty to fraud in Boston and was imprisoned in Toronto. In 2000, Kelly represented Marty McSorley during the latter's trial in Vancouver for on-ice assault with a hockey stick. Kelly was appointed as executive director of the NHLPA, replacing Ted Saskin, ousted for secretly monitoring player e-mail accounts.

Kelly was in favour of adding an NHL team in Canada. On August 31, 2009, Kelly was unexpectedly fired as head of the National Hockey league Players' Association following several hours of meetings in Chicago. Russ Conway, the former Lawrence Eagle Tribune NHL and Boston Bruins sportswriter who had helped to expose Alan Eagleson's corrupt practices, described Kelly as the first "true, clean" leader the NHLPA had, said "this is a sad day for hockey; the union continues to drink the Kool-Aid." Some have speculated. Ron Pink, the advisory board head, who had applied for Kelly's position in 2007, an ombudsman, Buzz Hargrove were instrumental in the decision to dismiss Kelly. Hargrove, Ian Penny, Ian Pulver and Eric Lindros were said to represent the "old guard of the NHLPA", one, confrontational and focused on driving up player salaries, rather than the overall financial well-being of the league, believed that the union conceded too much in negotiations during the 2004-05 lockout. Kelly was not involved with the NHLPA.

Penny was named the interim director that day. Donald Fehr became the permanent executive director on August 26, 2010. In November 2009, Kelly was hired as executive director of College Hockey, Inc. an organization set up by the commissioners of the six men's Division I college ice hockey conferences to promote college ice hockey as an option for potential recruits. The organization advises colleges looking into the possibility of adding NCAA Division I ice hockey. Kelly has been a practicing trial lawyer for over 30 years, with extensive experience in white collar criminal defense, internal investigations, complex civil litigation and crisis management, he is chair of the firm's White Government Enforcement practice group. A former sports industry executive, he is co-chair of the firm's Collegiate & Professional Sports Industry practice group. CBC.ca article TSN.ca article NHL Players' Association biography