Brock University Digital Repository
Brock University's Digital Repository is an online archive showcasing and preserving the Brock community's scholarly output as well as items from the Library's Archives & Special Collections. Researchers can disseminate their work by depositing it in this Open Access repository, which provides free, immediate access to users while also allowing Brock scholars to track downloads and views of their scholarship. The Digital Repository is also the home of the Brock University E-Thesis Portal.
For more information, see the repository's policies and procedures.
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Recent Submissions
Optimal and Robust Designs of Progressive Stress Loading Accelerated Life Tests under Progressive Type II Censoring
Yujia Luo
In traditional life testing experiments, it is often difficult to observe failures in highly reliable products due to their long lifespans, especially under normal operating conditions. Accelerated life tests (ALT) is a widely used strategy to obtain sufficient failure data within a shorter period. This project focuses on developing optimal and robust designs for ALT using progressive stress loading plans under progressive Type-II censoring. The underlying lifetime distributions are assumed to be either exponential or Weibull. Optimal designs are derived based on three different criteria: c*-optimality, D-optimality, and A-optimality. The resulting designs demonstrate high efficiency. However, these optimal designs are only locally optimal, as they depend on unknown parameters that must be estimated. To address this uncertainty, we adopt a minimax approach to identify robust stress loading rates that minimize the maximum potential loss. The resulting minimax designs are shown to be robust over a plausible range of parameter values.
Diversity of Tomato Brown Rugose Fruit Virus in Canadian Greenhouses
(Brock University) Fougere, Gregory Charles; Griffiths, Jonathan S; Despres, Charles; Department of Biological Sciences
Tomato brown rugose fruit virus (ToBRFV) has been a serious threat to greenhouse tomato production worldwide since its emergence in 2014 in Israel and Jordan. A member of the Tobamovirus genus, ToBRFV’s ability to break the longstanding Tm-22 resistance gene and ease of mechanical transmission has allowed the virus to spread rapidly through greenhouses worldwide. Little is known regarding the extent and genomic diversity of ToBRFV in Canada, despite the major impacts of this virus on greenhouse tomato production. 15 new Canadian ToBRFV genomic sequences have been determined, combined with 5 additional Canadian ToBRFV isolates retrieved from GenBank, and 5 consensus sequences assembled from a Canadian metagenomics wastewater monitoring study. The 25 Canadian sequences were combined with 332 international ToBRFV isolates to create a global phylogeny. Most Canadian isolates grouped together with other North American isolates but, several isolates branched separately, suggesting multiple introductions of ToBRFV to Canadian greenhouse systems. Canadian isolates sequenced in 2019 and 2024 originating from three different greenhouses grouped together, suggesting transmission of ToBRFV between greenhouses in Canada, showing that biosecurity of greenhouses is vital for the control of ToBRFV. Focused analysis on individual viral ORFs show the p126 and movement protein (MP) are the most variable regions of the genome. Novel mutations unique to Canadian isolates of ToBRFV were identified in both the p126 and MP. In the p126, 5 mutations were found in an area previously shown to directly interact with the TM-1 protein. Three of these mutations were unique to Canadian ToBRFV isolates and may be novel Tm-1 breaking mutations. In the MP, four novel mutations were identified that do not appear to be associated with Tm-22 and are potentially involved in breaking resistance mediated by an unknown resistance gene. Additionally, 7 isolates from greenhouse 2 had mutations in both the p126 and the MP, suggesting the virus has acquired potential resistance breaking mutations for multiple resistance genes. Until more robust resistance is identified, ToBRFV will continue to be a major threat to greenhouse tomato production in Canada.
The Press, Volume 30, Issue 25, March 17, 1994
(1994-03-17) Mathieu, Nick (Interim Editor); Hagley, Rob (News Editor); Flanagan, Maureen (Features Editor); Guzda, David (Arts and Entertainment Editor); Healey, Craig (Sports Editor); Antoniou, Jim (Photo Editor); Nickles, Greg (Illustration); Woodward, Paula (Ad Director); Palmer, R. (News Assistant); Jacklin, Sharron (Proofreader); Turner, Delaney (Entertainment Assistant); Parker, Andy (Sports Assistant); Moreau, Shawn (Photo Assistant); Noll, Paul (Production Manager); Granger, Curtis (Ad Assistant); Englefield, F. Ross (Editor Emeritus); Crawford, Lisa (Arts Contributor); Rogers-Watson, Chris (Writer)
The Press, Volume 30, Issue 25 includes: BUSU audits The Brock Press;
Brock faculty responds to $10k entrance proposal; Todd Oliver, BUSU VP of Finance resigns; Brock ranks 13th out of 23 universities by MacLean’s.; Brock Business Society holds first election; Zero tolerance University policy discussed in Focus section; Thirty Years of Brock Poetry: Collection of poems about Brock and the Niagara region previously printed in The Press over the years; Out-RAGE-Us column about bisexuality.
The Press, Volume 30, Issue 24, March 10, 1994
(1994-03-10) Mathieu, Nick (Interim Editor); Hagley, Rob (News Editor); Flanagan, Maureen (Features Editor); Guzda, David (Arts and Entertainment Editor); Healey, Craig (Sports Editor); Antoniou, Jim (Photo Editor); Nickles, Greg (Illustration); Woodward, Paula (Ad Director); Palmer, R. (News Assistant); Allen, S. (Proofreader); Jacklin, S. (Proofreader); Turner, Delaney (Entertainment Assistant); Parker, Andy (Sports Assistant); Moreau, Shawn (Photo Assistant); Noll, Paul (Production Manager); Granger, Curtis (Ad Assistant); Englefield, F. Ross (Editor Emeritus); Crawford, Lisa (Arts Contributor)
The Press, Volume 30, Issue 24 includes: Brock open house; CBC Radio’s Lister Sinclair speaks at Brock; Students who pay an extra $10k to Faculty of Ed can get into reserved spots; Brock Christian Fellowship sponsors 30-hour famine; “How Many Definitions of Feminism Are There?” Focus story “he says, she says” perspectives; Article on new reproductive technologies; Letters unsatisfied about The Brock Press’ coverage of BUSU candidates; Comedian John Candy dies; The Brock Press’ 1994 Election Guide.
The Press, Volume 30, Issue 23, March 3, 1994
(1994-03-03) Mathieu, Nick (Interim Editor); Hagley, Rob (News Editor); Flanagan, Maureen (Features Editor); Guzda, David (Arts and Entertainment Editor); Healey, Craig (Sports Editor); Antoniou, Jim (Photo Editor); Nickles, Greg (Illustration); Woodward, Paula (Ad Director); Palmer, R. (News Assistant); Allen, S. (Proofreader); Jacklin, S. (Proofreader); Turner, Dealney (Entertainment Assistant); Parker, Andy (Sports Assistant); Moreau, Shawn (Photo Assistant); Noll, Paul (Production Manager); Granger, Curtis (Ad Assistant); Crawford, Lisa (Arts Contributor)
The Press, Volume 30, Issue 23 includes: Maths professor Dr. Pat Rodgers speaks at Brock; New residence accommodating 256 students to be completed by 1995; Naomi Wolf to speak for International Women’s Week;
The Press doesn’t print secret BUSAC documents that would quell allegations about the Press, editorial; BUSU elections coverage. All candidate profiles for BUSU and BUSU president.