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Antibacterial activities of Propionibacterium acnes bacteriophages against a diverse collection of P. acnes clinical isolates: prospects for novel alternative therapies for acne vulgaris
No full textA total of 136 chronically infected Canadian acne patients from Ottawa-Gatineau and
Northeastern Ontario regions accounting for 75% of subjects (12-50 years old, with 90th
percentile at the age of 30) who had suffered acne vulgaris (with various acne related scarring)
for a median duration of 4 years, were sources for isolation of Propionibacterium acnes, the
etiologic agent for acne vulgaris. Eighty-four percent of patients were subjected to various
treatment regimens with topical and systemic agents including in combination with 1-3 different
types of antibiotics (mean duration of 7 months). A diverse collection of 224 clinical P. acnes
isolates from Canadian and Swedish subjects were characterized for their sensitivities to
infection by a Canadian collection of 67 diverse phages belonging to siphoviridae; and multiple
minimal cocktails consisting of 2-3 phages were formulated to be effective on global P. acnes
isolates. Propionibacterium acnes isolates were characterized by multiplex PCR to belong to
phylotypes IA, IB and II, which also showed resistance against commonly used antibiotics for
treating acne vulgaris (overall resistance rate of 9.5%), were sensitive to phages regardless of
their type and antibiotic resistance patterns, providing ground for phages as novel alternative
therapeutics for future in vivo trials. The phage collection was diverse by virtue of their BamHI
restriction patterns and full genome sequences and harboured a major tail protein (MTP) that
appeared to be important in contributing to their host ranges. Three dimensional structural
modeling of the N-domain of P. acnes MTPs implicated previously unreported involvement of
the α1-β4 loop (C5 loop) within N-domain amino acid sequence in contributing to the expanded
host range of a mutant phage to infect a naturally phage resistant P. acnes clinical isolate. Given the potential of phages for rapid mutational diversification surpassing that of their bacterial hosts and the fact that phages are generally regarded as safe (GRAS), rapid and cost-effective derivation of mutant phages with expanded host ranges provide a strong framework forimproving phage cocktails for use in future personalized medicine
Incorporating cut-off grade optimization and stockpiling into oil sands production scheduling and waste management.
Get PDFIn achieving maximum benefit in oil sands mining, the long-term production schedule should
have the time and sequence of removing ore, dyke material and waste from the final pit limit. An
optimum cut-off grade profile and stockpiling will ensure the segregation between these
materials meet economic and regulatory requirements. In-pit waste management strategy for oil
sands mining requires dyke construction to occur simultaneously with the advancement of
mining operations. This research seeks to determine: 1) the optimum life of mine cut-off grade
profile and its corresponding tonnages; 2) the time and sequence for removal of ore, dyke
material and waste to maximize NPV; 3) the dyke material schedule for dyke construction to
minimize construction costs; and 4) the associated impacts of stockpiling and stockpile
reclamation with limited time duration. Cut-off grade optimization was used to generate an optimum grade schedule which specifies the
cut-off grade, duration of mining of the grade and tonnage mined during the mine life. A
heuristic framework, referred to as the Integrated Cut-Off Grade Optimization (ICOGO) model
was developed in this research. It generates an optimum cut-off grade policy and a schedule for
mining ore and waste, as well as overburden, interburden and tailings coarse sand dyke material
for long-term production planning. Subsequently, a mathematical programming framework
based on Mixed Integer Linear Goal Programming (MILGP) model was developed to generate a
detailed production schedule for removal of ore, waste and dyke materials from the final pit
limit. Stockpiling scenarios investigated during the study include: i) no stockpiling; ii)
stockpiling and reclaiming at the end of mine life; and iii) stockpiling for one year or two years prior to reclamation. The developed models were applied to two oil sands case studies to maximize the Net Present
Value (NPV) of the operations. In both case studies, the NPV generated by the ICOGO model
for one year stockpiling scenario was higher than other stockpiling scenarios. For the MILGP the
NPV generated for the two year stockpiling scenario was higher than the one year stockpiling
scenario. In comparison, whereas the ICOGO model solved the optimization problem faster, the
MILGP model results provide detailed mining-cut extraction sequencing for mining
Geography Products for the 2016 Census of Population
No full textAn overview of Census geography products from the 2016 Census of Population
Examination of gene deletion as a mechanism of RBM5 downregulation in tobacco smoke-associated lung cancer
Get PDFRBM5 is a tumour suppressor gene with substantially decreased expression in most lung cancers,
especially in smokers, that may result from gene deletion. The objective of this study was to
determine if significantly decreased levels of RBM5 expression in the lung cancers of smokers
was related to RBM5 deletion. Using DNA from patient lung tissue, RBM5 gene copy number
was quantified by quantitative polymerase chain reaction. Although deletions were detected in
the lung specimens, RBM5 gene copy number was not significantly decreased in lung tumours.
RBM5 deletions were detected in the non-tumour DNA of smokers, but not in the never-smokers,
indicating that RBM5 gene deletion might be related to smoking. In conclusion, it appeared as
though RBM5 was downregulated by more than one mechanism, which included gene deletion.
Further analyses must be carried out to examine other mechanisms by which RBM5 is
downregulated
Edge detection in unorganized 3D point cloud
Get PDFThe application of 3D laser scanning in the mining industry is increasing progressively over the
years. This presents an opportunity to visualize and analyze the underground world and potentially
save countless man- hours and exposure to safety incidents.
This thesis envisions to detect the “Edges of the Rocks” in the 3D point cloud collected via scanner,
although edge detection in point cloud is considered as a difficult but meaningful problem.
As a solution to noisy and unorganized 3D point cloud, a new method, EdgeScan method, has been
proposed and implemented to detect fast and accurate edges from the 3D point cloud for real time
systems. EdgeScan method is aimed to make use of 2D edge processing techniques to represent
the edge characteristics in 3D point cloud with better accuracy. A comparisons of EdgeScan
method with other common edge detection methods for 3D point cloud is administered, eventually,
results suggest that the stated EdgeScan method furnishes a better speed and accuracy especially
for large dataset in real time systems
Utilization of industrial waste heat for the cultivation and harvesting of microalgae
Get PDFMicroalgae sourced lipids that can be transesterified into biodiesel are a promising source
of biofuels that can be produced while mitigating industrial carbon dioxide (CO2) in offgasses.
There are many advantages to microalgae compared to other bio-feedstocks,
including their rapid growth rate, their ability to accumulate significant amounts of lipid,
and the possibility of year-round production. However, there are significant limitations to
achieving wide spread and economic microalgae mass cultivation and two of these are
addressed in this research program. Microalgae cultivation is currently generally limited to climatic zones where
temperatures remain above 15°C, which effectively restricts mass cultivation to tropical
or sub-tropical regions thereby eliminating the use of a number of worldwide industrial
CO2 sources. However, many of these sources also produce significant amounts of waste
heat. The capture and repurposing of waste heat to maintain culture temperature and
provide an alterative method for harvesting was explored. A dynamic model was
developed to determine the potential of waste streams from a nickel smelter to maintain
year-round growth in a cold climate. From this model, it was determined that there is
more than enough heat to maintain cultivation temperatures even when the ambient
temperature drops well below freezing. Harvesting of microalgae prior to lipid extraction is, with current approaches, often cited as an area where costs need to be significantly reduced. As a wholly novel approach, the capture of this waste heat was also explored for the use as a pretreatment for harvesting
by flotation. It was determined to be highly effective and crucially avoids the addition
and costs of chemical coagulants, which contaminate and restrict the use of the remaining
biomass after lipid extraction
A study of the late-stage mineralogy of agpaitic environments: borosilicates, niobate hydrates and development of laser ablation ICP-MS as a tool to analyze for high concentrations of light elements (Li, Be, and B)
Get PDFTo date, over 400 mineral species have been discovered at Mont Saint-Hilaire (MSH) many of
which are new to science. These new minerals tend to occur as late-stage phases with an
enrichment high field strength elements (HFSE) (i.e. Nb, Ti, Zr) as well as light elements (i.e. Li,
Be and B). Characterization of these minerals has been hindered by their small crystal sizes (i.e.
μm scale) as well as enrichment in light elements. This thesis discusses the chracterization and
overall implications of franconite group minerals as well as the new boro silicate minerals
steedeite and nolzite. Finally the effectiveness of laser ablation ICP-MS as a method of
accurately measuring major concentrations of light elements is discussed. Franconite group minerals (FGM) are hydrous-alkali niobates, inferred to have formed from Nbrich
precursor minerals at low temperatures (~150 °C). The structures of these minerals are held
together by hydrogen bonds and are highly flexible with Na, Ca, Mg and possilbly Fe2+ and K
substituting for one another. Although FGM are Nb-rich, they are notably devoid of Ta despite
the two elements being geochemical twins. The FGM are crystallo-chemically similar to scandia
octahedral molecular sieves, a group of synthetic compounds known for their cation exchange
properties. Twelve borosilicate phases, including the new minerals steedeite and nolzeite are known from
MSH. These are crystallo-chemically similar, both minerals containing of single loop-branched
dreier chains in their structures. Such chains occur in synthetic compounds (e.g.
Li2Mg2[Si4O11]) but are not known to occur in other naturally occurring minerals. Steedeite is
highly ordered with respect to Si and B whereas nolzeite contains a mixed Si/B site despite the
two minerals being associated with one another. Accurate chemical analysis of late-stage minerals, rich in light elements, is hindered by the fact
that such elements have low atomic masses. Laser ablation ICP-MS analysis of a variety of
mienrals with major concentrations of light elements gave measured concentrations of Li, Be and
B that were within ± 10% of expected ideal values for most minerals. Beam widths varying from
6 to 30 μm were employed however; they had no effect on the measured light element
concentrations. Four standards including the NIST610 & 612 glasses, natural beryl, and lithium
metaborate were used. Of these NIST610 is considered the most suitable as it has the smallest
associated errors (1σ error: ± 0.05 to ± 1.68 ppm). Based on this LA-ICP-MS is considered to be
a suitable alternative to secondary ion mass spectrometry for analysis of light elements
Retrospective analysis of mine seismicity: Glencore, Kidd Mine
No full textUnderstanding the rock mass response to underground mining is a significant benefit to assist with decisions aimed at maintaining safe access and controlling conditions in which incidents of rock mass failure may occur during excavation development. As Canadian mines get deeper, high stress conditions become more prevalent, often leading to dynamic rock mass failure. This failure results in recordable dynamic stress waves, also called mining induced seismic events. The occurrence of large seismic events has become commonplace in many Ontario hardrock mines.
This thesis investigates the mining-induced seismic events recorded in the deepest levels of Glencore’s Kidd Mine, near Timmins, Ontario. The research focuses on mining-induced seismic events in Mine D, which is between 2000 and 3000 metres below surface. Spatial and temporal trends of large seismic events are investigated. Particular emphasis is placed on analysis of the variations in radiated seismic energy associated with large magnitude events.
Through analysis of seismic source parameters such as radiated seismic energy, a better understanding of dynamic rock mass failure in a mine is achieved. This improved understanding aids in managing the risks associated with deep mining in high stress conditions
The effect of the relationship to knowledge of physical education teachers on the ostensive forms in swimming
No full textThis article is interesting in ostensive forms of two physical education
(PE) teachers within the activity of Swimming in Tunisia. Its objective is to
analyze the ostensive forms of PE teachers and to extricate their effects on the
relationship to knowledge. The methodology of the research is qualitative. It
subscribes in the field of didactic clinical interactions of PE and on the clinical
analysis of teaching practice of an experimented and a novice teacher in order
to glimpse « case by case » the singular subject (Terrisse, 1999). Data
collection and analysis subscribe in the constructed temporality in one time of
professorial action. The test (Terrisse, 2000) relies on the knowledge ostension
scale (Robert, 2012; Salin, 2002). Results put in evidence that PE teachers use
ostensive forms to influent the relationship to knowledge in Swimming
Wikidata for librarians: CAML 2017 preconference
No full textA presentation on editing Wikidata with a specific focus on musicians, bands, and music festivals. Presented at a preconference of the Canadian Association for Music Libraries, Archives, and Document Centres (CAML) 2017 conference in Toronto, Ontario