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Effects of nickel toxicity on seed germination and expression of genes associated with nickel resistance in Populus tremuloides
No full textAlthough Nickel is an essential nutrient for plant growth in low concentrations, its excessive
amounts in soil above threshold values can result in toxicity. The main objectives of the present
research were to determine the effects of different doses of nickel on a) trembling aspen
(Populus tremuloides) seed germination and b) gene expression. This study revealed that nickel
in agarose media even at a low dose inhibits seed germination. In soil however, only the highest
dose of 1, 600 mg of Ni per 1 kg of soil has detrimental effects on germination of P. tremuloides
seeds. P. tremuloides seedlings were resistant to 150 mg /kg, 400 mg /kg, and 800 mg /kg of Ni
doses in growth chamber screening tests. At high Ni dose of 1, 600 mg /kg, differential responses
were observed as Ni- resistant, moderately resistant, and susceptible genotypes were identified.
Expression of the AT2G16800 gene was repressed with increasing nickel concentration and this
effect was most significant at the 800 mg/kg Ni dose. Surprisingly, the study also revealed that
the higher concentration of potassium nitrate without nickel (800 mg/kg and 1, 600 mg/kg)
induced a significant upregulation of the NAS3 and NRAMP4 genes
Geological characterisation guided by fuzzy k-means clustering of physical properties measured from core samples from the Victoria property, Sudbury Ontario
No full textCore logging is a subjective practice done by geologists, which documents the mineralogy,
textures, alteration, mineralisation and other features to give core a rock name. Pattern
recognition techniques are able to characterise the rocks and link the geophysical and geological
data quantitatively. The fuzzy-k means algorithm is an unsupervised pattern recognition
technique, which groups data into clusters based on properties measured. This study will use the
fuzzy-k means algorithm to characterise core samples from 2 drillholes from the Victoria
property in Sudbury with thin section examination to identify how mineralogical changes can
affect the measurements. Four different physical properties (density, gamma ray, conductivity
and magnetic susceptibility) were measured from a total of 203 core samples of quartz diorite,
metagabbro, metabasalt, pyroxenite, olivine diabase and metasedimentary rocks. The samples
were classified into 4 different physical units, with additional confusion index values that
indicate how well the data was classified. Quartz diorite, metagabbro and metabasalt have the
highest confusion index values while the olivine diabase and metasedimentary rocks have the
lowest confusion index values. Combining the fuzzy k- means results and thin section
examination proved to be successful because heterogeneities in sulphide minerals, ore
mineralisation and variation in rock forming minerals cause an overlap in physical properties
with other rock samples, increasing the confusion index while homogeneity in mineralogy results
in a low confusion index
The geology of the Beardmore-Geraldton belt, Ontario, Canada: geochronology, tectonic evolution and gold mineralization
No full textThe Beardmore-Geraldton belt (BGB) is a greenstone belt straddling the boundary between the
eastern Wabigoon subprovince and the Quetico metasedimentary subprovince. It consists of shearbounded panels of metavolcanic and metasedimentary rocks which were imbricated during an
early thrusting event and regionally folded and sheared during subsequent deformation events. It
hosts several historic gold mines with a combined past production exceeding 4 Moz gold. New
gold resources were delineated within the last ca. 10 years at the Hardrock deposit in the eastern
part of the belt which highlighted the need for a better understanding of the controls on gold
mineralization in the belt.
The BGB comprises three panels of metasedimentary rocks, representing a southward transition
from fluvial to deltaic to deep oceanic basin plain environments, overlying three panels of older,
ca. 2725 Ma, metavolcanic rocks, representing back arc, island arc, and oceanic crust. Detrital
zircon geochronology of the BGB and adjacent northern Quetico metasedimentary rocks suggests
that these rocks formed from sediments derived by the erosion of ca. 2700 Ma to 2900 Ma source
rocks and older >3200 Ma Mesoarchean craton of the eastern Wabigoon subprovince. The
emplacement of crosscutting 2694±1 Ma feldspar-quartz porphyry (FQP) dikes, marks the end of
sedimentation in the belt. The panels were subsequently imbricated during an early thrusting event
(D1) which ended with the emplacement of the stitching 2690±1 Ma Croll Lake stock. The
composition of the FQP dikes and Croll Lake stock (i.e. SiO2, ferromagnesian oxide and transition
element contents, [La/Yb]N ratio) indicate a shift from tonalite-trondhjemite-granodiorite (TTG)
suite to sanukitoid suite magmatism over a 4 Ma period. The formation of the sanukitoid melts,
which involves the addition of a mantle melt component, is consistent with their generation during
delamination or slab break-off as the BGB metavolcanic and metasedimentary panels were thrustimbricated and accreted to the Wabigoon subprovince during closure of the Quetico basin.
D1 structures are expressed by early, isoclinal, F1 folds with an axial planar S1 cleavage. They are
folded by regional F2 folds with an axial planar, regional, S2 cleavage, which becomes more
pronounced along belt-parallel, sinistral, high strain zones characterized by asymmetrical, Sshaped F2 folds and NE-striking, en echelon, quartz-carbonate veins. The association of regional
folds and cleavage with sinistral high strain zones suggest that these structures formed during
regional sinistral transpression (D2) across the belt. During subsequent dextral D3 transpression,
the regional F2 folds and S2 cleavage were overprinted by Z-shaped F3 folds and by a second
regional cleavage (S3), and the D2 high-strain zones were reactivated as dextral shear zones. Within
the reactivated high strain zones, F1, F2 and F3 fold axes are parallel to a strong, shallowlyplunging, stretching lineation that formed during D2 and was accentuated and rotated towards the
orientation of the fabric attractor during D3. The fabric attractor is oblique to the intersection
lineation between the reactivated S2 cleavage and dextral shear bands, suggesting that the
deformation during D3 had triclinic symmetry.
The Hardrock gold deposit is one of several deposits hosted by the Bankfield-Tombill deformation
zone near Geraldton in the eastern part of the BGB. Gold was emplaced during early D1 thrusting
and D2 sinistral transpression in association with strongly folded, early D1, quartz-carbonate veins
(V1) and E- to NE-striking, syn-D2, tourmaline-rich (V2) and quartz-carbonate veins (V3) veins.
Gold is present in association with inclusion-rich pyrite with elevated Au, Ag, As, Bi, Co, Ni, Pb,
Sb, Te concentrations and along fractures and as inclusions in the veins and sulfides. The deposit
is surrounded by a broad (≤250 m) alteration envelope of carbonate and sericite with elevated
pathfinder S, Te, As, W, and Bi concentrations. Early introduction of gold in the belt during
thrusting and sinistral transpression differs from previous studies which favored late tectonic
emplacement of gold in D3 shear zones and fold hinges
Northeastern Ontario registered nurses’ perceptions of E-learning
No full textNurses face challenges in meeting their continuing education needs. E-learning can help
to overcome these barriers and has become a common method of nursing continuing education.
An integrative literature review found that e-learning benefits nurses’ learning, patient care, and
the hospital organization in different international contexts. E-learning has unique barriers, areas
for improvement, and additional research is needed in the Northeastern Ontario context.
An interpretive description qualitative study explored the perceptions of ten Northeastern
Ontario registered nurses about e-learning. The aim was to understand this phenomenon and
inform continuing education practices. Bridging the Gap was the overarching theme, providing a
rich description of how nurses perceived e-learning as a continuing educational method. The
overarching theme was supported by the subthemes: Unsatisfactory Learning Experiences,
Meaningful Learning Experiences, and Enhancing Learning Experiences. These findings could
inform future e-learning continuing education and support patient care
A rhetorical analysis of wind concerns Ontario's use of melodrama to promote online opposition to industrial wind turbine developments
No full textIn 2009, the Ontario government implemented the Green Energy Act (GEA). Within this
initiative, the GEA heavily subsidized renewable energy developments and instituted procedural
mechanisms to expedite such developments across the province. In doing so, the GEA altered
the landscapes of numerous rural Ontario communities. Since 2009, nearly 2 500 industrial wind
turbines (IWTs) have been constructed – turbines approximately 80 meters high with blades
exceeding 40 meters. In response to this alteration, roughly 50 grassroots groups have
designated themselves as “Not A Willing Host” of IWTs. This phenomenon represents a paradoxical “green on green” (Warren et al. 2005) controversy in
which pro-environmental arguments figure centrally (though not exclusively) within grassroots
opposition to a government-led ‘green’ initiative.
To understand the scope and style of these arguments as a form of environmental
communication, my dissertation undertakes a textured rhetorical analysis of Wind Concerns
Ontario’s (WCO) online opposition – the most prominent grassroots IWT opposition group
within the province.
Drawing on Schwarze’s (2006) theory of environmental melodrama, my rhetorical analysis
illustrates that WCO’s use of ‘embedded third-party edited blog posts’ constitutes an
environmental melodrama – a melodrama that is enacted through WCO’s appropriation of
journalistic conventions. In communicating these posts, WCO often inserts its own headline,
lead, visual and/or caption to frame the linked item as part of its oppositional discourse. I argue that this complex and contemporary rhetorical strategy functions as a form of participatory
journalism to promote political homophily and create an echo chamber in which the ideological
underpinnings of IWT opposition coalesce and reverberate, while contrary ideologies are
dismissed.
This research contributes to further mapping the parameters of the IWT controversy in Ontario.
It also contributes to an understanding of the rhetorical repertoire of environmental melodrama
by highlighting its discursive complexity and malleability – notably the incorporation of
technocratic discourse conventions and divisive humour – two features not typically associated
with this rhetorical form. Furthermore, by exploring the characteristics and implications of
melodrama – a rhetorical form common in public disputes – this research will inform citizens
and stakeholders who find themselves imbricated amidst a social controversy, environmental or
otherwise, and navigating a potential rhetorical response
Baking power: French-Canadian and Franco-Ontarian cultural identity as defined by evolving traditional foodways in Astorville, Ontario
Get PDFQuestions about cultural identity and allegiance are complicated. What makes a person French,
French-Canadian or Franco-Ontarian? What is the difference between these various labels? How do
demographics, gender, and age impact the ways in which cultural allegiance is created, maintained, or
discarded? What defines a person’s membership in a cultural group? Is it one’s ability to speak the
language? To make and/or eat cultural foods? If one of these fails to be present, can the person still be a
part of the group? In our multicultural country, and especially in rural communities in Northern Ontario
where Francophones find themselves to be part of a minority, such questions do not have simple
answers. Studying cultural retention in such communities necessitates paying attention to more than just
who is speaking French and/or to who is an activist for French rights. It also requires understanding how
individual attitudes and behaviours are like and/or unlike those of others and of the larger group.
Foodways are one of the specific cultural practices that can tell us about the group. Indeed, traditional
foods have been shown to be very political expressions of personal values and opinions. What power
does French-Canadian food have over those who make it? What does it tell us about those who claim
allegiance to this cultural group?
This interdisciplinary case study of Astorville, Ontario, relates to the fields of food studies,
cultural studies, history, gender studies, material culture studies, performance studies, and
autoethnography. By studying foodways, which are closely connected to heritage, language, religious
practices, and rituals, this project seeks to understand how minority groups resist and/or acquiesce to
societal pressures to conform to the culture of the majority. Knowing that modernisation and
urbanisation have changed the lifestyle of once agricultural communities, that women now participate in
the workforce, and that an individual’s personal history is an important factor in determining how one
subscribes to cultural norms, this is an important time to understand the cultural evolution taking place
in communities, like Astorville, Ontario, where the French population has gone from a majority to a
minority since it was established
The synthesis of macrocyclic molecules related to telomestatin
Get PDFG-quadruplex DNA represents an attractive target for the development of anti-cancer therapeutic agents as it plays important roles in transcriptional regulation and the maintenance of telomeric length. Oxazole-containing macrocycles such as telomestatin are considered to be a promissing new class of G-quadruplex binding ligands. In this work, poly-oxazole building blocks were synthesized to prepare a tetraoxazole peptide macrocycle in good yield. The macrocycle was obtained by employing standard peptide coupling conditions using a convergent solution phase approach. The synthetic unit of the oxazole amino acid containing compound was prepared by cyclodehydration/oxidation of protected serine and phenylalanine. Two-cycle coupling of the unit gave a linear tetraoxazole amide. The final macrocyclization was accomplished by using O-[(1-cyano-2-ethoxy-2-oxoethylidene)amino]-oxytri(pyrrolidin-1-yl) phosphonium hexafluorophosphate (PyOxP) and the product (45% yield) was characterized by 1H NMR. Finally, the Cu (II) coordination chemistry of the tetraoxazole macrocycle was investigated by spectrophotometric titration
Origin of post-collisional magmas and formation of porphyry Cu deposits in southern Tibet
Get PDFThe recent discovery of large porphyry copper deposits (PCDs) associated with Miocene (22–12 Ma) granitoid
magmas in the eastern section of the Paleocene-Eocene Gangdese magmatic arc in the Himalaya-Tibetan orogenic belt raises new questions about the origin of water-rich (≥4.5 wt.%), oxidized (ΔFMQ 1–3) magmas in continental collisional settings and their mineralization potential. We review the literature and compile available data on whole rock and isotope geochemistry for Cenozoic igneous rocks from Tibet, and add new zircon Ce4+/Ce3+ and Ti-in-zircon thermometry data to better understand variations in oxidation state and thermal evolution of these suites, which are key controls on Cu mineralization. Six distinct Cenozoic igneous suites are defined: Paleocene-Eocene syn-collisional Gangdese magmatic arc rocks (ΔFMQ = -1.2 to +0.8) (suite I), and five broadly contemporaneous Miocene suites. A distinct change in magmatism along the length of the belt occurs at around 88°E in the Miocene suites: to the east, porphyry copper mineralization is associated with a moderately oxidized, high-Sr/Y granitoid suite (suite II, ΔFMQ = +0.8 to +2.9) with minor occurrences of transitional (hybrid) monzonitic (suite III) and trachytic rocks (suite IV; both with
zircon Ce4+/Ce3+ > 50-100, EuN/EuN* = ~0.5, and ΔFMQ = ~+1 to +2). To the west of 88°E, trachytic volcanic rocks (suite V) are more voluminous but more reduced (zircon Ce4+/Ce3+ < 50, ΔFMQ <+1), and are associated with sparse, poorly mineralized high-Sr/Y granitoids (suite VI) which are moderately oxidized (zircon Ce4+/Ce3+ = 20–100, ΔFMQ = ~+1 to +3). The Miocene high-Sr/Y granitoids have many compositional and isotopic similarities to the Paleocene-Eocene Gangdese arc rocks, and are interpreted to have been derived by melting of the hydrated arc root, with minor mantle input. In contrast, the highly evolved isotopic signatures of the Miocene trachytic rocks, combined with deep seismic profiles and a xenolith-derived geotherm, suggest their derivation from the underthrust Indian Proterozoic subcontinental lithospheric mantle (SCLM) or old fore-arc Tibetan SCLM during phlogopite breakdown at temperatures of ~1100°C. Based on published geophysical data and tectonic reconstructions, we develop a model that explains the origin of the various Miocene magmatic suites, their spatial differences, and the origin of related PCDs.
Following the early stages of continental collision (Eocene–Oligocene), shallow underthrusting of the Indian continental lithosphere and subcretion of Tethyan sediments (including oxidized carbonates and possibly evaporites) under eclogite facies conditions promoted the release of aqueous fluids, which hydrated and oxidized the base of the overlying Tibetan plate. This metasomatism rendered the Tibetan lower crust fusible and fertile for metal remobilization. During the mid-Miocene, the Indian slab steepened in the eastern sector (east of ~88°E). In this eastern belt, deeply derived trachytic magmas were trapped in melt zones at the base of the Tibetan crust, and variably mixed with the crustally-derived, high Sr/Y granitoid magmas. They may also have released water that contributed to fluid-fluxed melting of the lower crust, producing voluminous high-Sr/Y granitoid magmas, which were associated with significant PCD mineralization. Hybridization between the trachytic magmas and lower crustal partial melts is indicated by intermediate isotopic compositions, enriched Cr and Ni contents, and high Mg# in some intermediate-to-felsic (56–70 wt. % SiO2) high-Sr/Y granitoids. Trapping of the trachytic melts in deep crustal melt zones explains the relatively small volumes of trachytic magmas erupted at surface in the east. In contrast, to the west of ~88°E, subduction of the Indian plate has remained flat to the present day, preventing incursion of hot asthenosphere. Consequently, cooler conditions in the deep Tibetan lithosphere resulted in limited crustal melting and the production of only small volumes of high-Sr/Y granitic magmas. Trachytic melts ascending from the underthrust
Indian or Tibetan plate were able to pass through the cooler lower crust and erupted in greater volume at surface, whereas only small volumes of high-Sr/Y granitoid magma were generated and are not associated with significant PCD mineralization
L’effet de la durée, l’intensité et la dépense énergétique de l’exercice sur la consommation d’oxygène post-exercice (EPOC) chez les adolescentes sédentaires
Get PDFLes taux d’obésité au Canada continuent à s’accroitre. Cette tendance est particulièrement inquiétante chez les adolescentes étant donné les conséquences médicales, sociales et psychologiques associées à l’obésité. Bien qu’il existe un nombre de traitements pour la perte de poids, l’impact de l’excès de consommation d’oxygène post-exercice (EPOC) sur le bilan énergétique n’a jamais été étudié auprès des adolescentes. L’objectif de cette étude est de déterminer l’effet de la durée, l’intensité et la dépense énergétique de l’exercice sur l’EPOC chez les adolescentes sédentaires. Huit adolescentes (15-17ans) ont complété 3 sessions expérimentales (30min à 61% du VO2max; 60min à 62% du VO2max; 36min à 76% du VO2max), suivies par 80 minutes de repos. L’EPOC n’a pas été influencé par la durée, l’intensité ou la dépense énergétique de l’exercice. Les adolescentes devraient donc être encouragées de participer à l’activité physique, peu importe les paramètres de l’exercice