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Sedimentology, stratigraphy, geochemistry, geochemistry and diagenesis of giant lacustrine carbonate seep mounds (Ikpiarjuk Formation), Mesoproterozoic Borden Basin, Nunavut, Actic Canada
No full textThe Ikpiarjuk Formation consists of a group of very large (kms long and hundreds of metres
thick), isolated, deep-water, vent-related dolostone mounds that are unlike any documented
example of vent-related carbonate rocks in the geological record. The mounds lack ‘normal’
features of Proterozoic carbonates: the mounds contain thrombolites (microbially clotted
carbonate), formed below the photic zone, and lack the stromatolitic fabric characteristic of most
Proterozoic reef structures. The sedimentology, stratigraphy, geochemistry, and diagenetic
history of the mounds were investigated through field work, standard petrographic methods, and
various geochemical and other analytical techniques.
Shale-normalised rare earth element patterns of various depositional components of the mounds
depicts binary mixing between basin-water-derived precipitates and seep-fluid-derived
carbonate. Basin fluid has characteristics that are consistent with deposition in an alkaline lake,
and seep fluid features are consistent with circum-neutral groundwater that had interacted
extensively with basement blocks before seeping into the lake bottom through faults.
The sedimentology and mineralogy of the mounds indicates that they were formed by
thrombolites that were made up of a microbiota that was not photosynthetic or aerobic. The
Ikpiarjuk Formation thrombolite microbiota was probably dominated by an anaerobic
chemoautotrophic or chemoheterotrophic metabolism, and records visible preservation of a
community that has never before been described from the Mesoproterozoic.
The diagenetic history of the Ikpiarjuk Formation is complicated. Dolomitisation occurred early
during diagenesis, and subsequently, five different fluids flowed through primary pore space in
the mounds and precipitated successive generations of cement. One of the cements contains
sulphides inclusions and may correlate with base-metal bodies elsewhere in the basin
The effect of personality and behaviour on muscle co-contraction ratios In the trunk when people are exposed to different types of emotional stimuli while performing a lateral bend and simple lifting task
No full textPsychosocial factors have long been implicated in occupational injury risk,
but the nature of this relationship is obscure. Recent investigations have concluded
that emotional responses affect muscle force outputs; which may, in turn, affect
joint loading. Personality type has also been shown to affect joint loading (Marras
et al., 2000). Likewise, there is an interaction between emotional stimuli and
personality. Exposure to pleasant emotional stimuli has been shown to facilitate
flexion movements; whereas exposure to unpleasant emotional stimuli has been
shown to facilitate extension movements (Coombes et al., 2008). However, it is not
clear what co-contraction ratio, and consequently what joint load, any given
emotional stimulus might result in, or how personality variables might affect this
relationship. To address this, participants filled out an International Personality
Inventory Pool (IPIP) Survey and a Behaviour Activation System and Behaviour
Inhibition System (BAS/BIS) Survey to determine each participant’s specific
personality and behaviour traits. Participants were then exposed to emotional
stimuli prior to a torso lateral bend, requiring both flexor and extensor cocontraction.
A total of 29 participants were tested. Participants were randomly
exposed to unpleasant, neutral, pleasant, and colour image types; 30 images in total.
They were exposed to these images for five seconds, then a tone sounded after
which they initiated a lateral bend. The current results indicate that image type had
no significant effect on flexor/extensor and left/right side co-contraction ratios.
Varying levels of personality and behaviour were the only factors to produce
significantly different co-contraction ratios. There was also a significant difference
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of left/right side co-contraction ratios between men and women, where men had
produce significantly greater right side dominant co-contraction ratios for all image
types compared to women.
The second part of the experiment had subjects stand on a force-plate and
listen to different types of emotional sounds. These sounds ranged from
unpleasant, pleasant, and neutral. Subjects would listen to a specific emotional
sound for six seconds, and after the sound was over, a voice would inform them to
lift a 15 pound crate off of the floor in front of them and place it on a table waist
height. The second sound would have subjects pick up the crate from the table and
place it back on the ground. This was done a total of 30 times with 30 different
sounds. The results indicate that sound type had no significant effect on cocontraction
ratios. Varying levels of personality and behaviour were the only
factors to produce significant changes in co-contraction ratios for both
flexor/extensor and left/right side co-contraction ratios. There were also significant
changes between co-contraction ratios and sex. Both men and women produced
flexor dominated co-contraction ratios for all sound types, but men produced
significantly higher flexor dominated co-contraction ratios for all sound types
compared to women. Men also produced significantly greater right side dominant
co-contraction ratios, compared to women, for all sound types
Molecular analysis of northern red oak (Quercus rubra) populations from the Greater Sudbury Region: genetic variation and gene expression
No full textThe main objectives of the present study were to 1) analyze genetic variability of Q. rubra
populations from the mining region of Sudbury (Ontario) using RAPD marker system and 2)
analyze the expression of nickel and copper resistance genes in Q. rubra populations. The level
of polymorphic loci within populations was high ranging from 61 % to 72% despite a high level
of gene flow (2.4) and the population differentiation (GST) value was low (0.17). All Q. rubra
populations analyzed were genetically sustainable. Moreover, this study revealed that all
populations were genetically closely related with genetic distance values varying from 0.17 to
0.35. A zinc finger protein of Arabidopsis thaliana (ZAT11) involved in nickel resistance was
differentially expressed in samples analyzed. There was a 120x up-regulation of ZAT11
expression in samples from metal contaminated areas of Wahnapitae Dam compared to other
sites. No association between soil metal levels and expression of ZAT11 was established
Validation of the use of Sus Scrofa (domestic pig) DNA as a research tool in a forensic laboratory
No full textFor a number of years, pigs have been used in a variety of forensic disciplines as a research tool, such as in forensic anthropology. However, pigs have not been used as a research tool in forensic DNA analysis. The use of pig DNA is becoming common in different areas of forensic science such as wildlife management but the transition to forensic DNA research has not happened yet. This paper proposes that pig DNA can be used in a forensic setting for research purposes in a lab that also conducts case work. The methods followed for the development of an STR profile using a commercial multiplex kit for pigs are the same as the standard procedure in a forensic Human DNA laboratory. The validation showed that pig DNA can be analyzed with the equipment currently used for human samples and it does not cross contaminate human samples. These factors would help small labs conduct both research and casework within the same laboratory
Hemagglutinin-based antigen designs expressed in the methylotrophic yeast Pichia pastoris
No full textThe Influenza virus is a significant global health problem whose worldwide circulation constantly triggers new pandemic strains often linked to genetic re-assortment and new mutations. Virus variability threatens and challenges the health of millions of citizens. Vaccination against influenza prior to infection offers the standard alternative to antiviral treatment in infected patients. Vaccine production must be available in sufficient volume for human and animal vaccination on a large scale. In this study I designed a novel recombinant influenza protein composed of three chimeric Hemagglutinin (HA) influenza receptor-binding domains (RBD) expressed in tandem. This construct was expressed as a single molecule in Pichia pastoris and characterized by gene sequencing, polyacrylamide gel electrophoresis, immuno-detection, and carbohydrate composition. The goal of this project is to develop a reagent for use in immunological response assays in a mouse model that will provide information regarding the potential use of these multisubunit gene-expressing constructs as vaccine candidates
The role of formate in combatting oxidative stress.
No full textAs all aerobic organisms are exposed to oxidative stress, they are known to devise
intricate mechanisms to counter reactive oxygen species (ROS). Metabolic networks
contributing to the production of ketoacids are prominent in alleviating the oxidative
burden. When glyoxylate detoxifies ROS, formate is the principal by-product generated.
In this study the contribution of formate in enabling the survival of the microbe
Pseudomonas fluorescens challenged by hydrogen peroxide (H2O2) has been elucidated.
When grown in the presence of H2O2 (stressed culture), the levels of formate were higher
in the spent fluid and the soluble cell-free extracts compared to the controls. Formate was
subsequently utilized as a reducing factor to produce NADPH and succinate. The former
is mediated by formate dehydrogenase (FDH-NADP), whose activity was enhanced in the
stressed cells. Fumarate reductase (FRD) that catalyzes the conversion of fumarate into
succinate was also markedly increased in the stressed cells. Metabolic adaptation is a pivotal tool in combatting oxidative stress. Formate, a by-product of glyoxylate- mediated
detoxification of ROS is recuperated as a potent reductive fuel. It is becoming quite evident
that this simple metabolite has other biological roles that have not been fully appreciated
Beyond the sandwich generation: the lived experiences of older Prince Edward Island women caregivers caring for an older adult
No full textThis research examined the experiences of older Prince Edward Island women in providing care to an aging parent, partner, family member, or friend. I investigated these experiences using a feminist lens to recognize the valuable experience of women and use their voice in bringing attention to the issues related to caregiving. This study was designed to answer three research questions:
1) What is the experience of older female caregivers living on Prince Edward Island?
2) What does it mean to be caregiver?
3) How do Prince Edward Island women describe caregiving?
These questions were designed to determine what experiences, meaning, and description caregivers assign to their work and what can be learned from these experiences.
Previous research in the field of caregiving has largely focused on quantitative measures of caregiver burden, activities of daily living, or access rates for caregiver support. I conducted one-to-one, in-depth interviews based on open-ended questions designed to encourage participants to share their experience. This qualitative study has advanced understanding of the caregiver experience on Prince Edward Island by highlighting the challenges faced in providing care, as well as the positive growth associated with the role.
The findings offer insights in engaging family caregivers in policy and strategy development and implementation. It also offers a vision for the continued integration of social work services for aging Islanders and their families. The need for specific skills and training in gerontological social work, including a focus in end-of-life care, advocacy, and counseling support has been demonstrated.Master of Social Wor
Synthesis of peptide-derived tetraoxazole containing macrocycles
No full textNatural macrocyclic peptides isolated from marine metabolites have shown
interesting biological activities, including anticancer properties. In addition, they are
highly pre-organized for metal inclusion due to their structural features, such as the
presence of a cavity with perfectly located oxygen and nitrogen donors within the
macrocyclic structure. This thesis pertains to the development of a synthetic approach
towards the synthesis of natural macrocyclic structures. These macrocyclic peptides
are made up of four oxazole rings connected by amide bonds with functionalized side
chains. A synthetic strategy for the synthesis of natural peptide-derived macrocyclic
analogues was developed using solution phase peptide synthesis. The synthesis of the
tetraoxazole macrocycle is described in more detail where the synthesis started with
the formation of a dipeptide by coupling two amino acids, followed by oxazole ring
formation, and subsequent formation of the di-, tri-, and tetraoxazole peptide. All of
the peptide bonds were obtained using O-(benzotriazol-1-yl)-N,N,N′,N′-
tetramethyluronium hexafluorophosphate (HBTU) or 1-ethyl-3-(3-
dimethylaminopropyl) carbodiimide hydrochloride (EDC.HCl) with
hydroxybenzotriazole (HOBt) with the base N,N-diisopropylethylamine (DIEA).
Finally, macrocyclization of the linear unprotected tetraoxazole gave the macrocyclic
structure. The macrocyclization was achieved efficiently by using (ethyl
cyano(hydroxyimino)acetato)-tri-(1-pyrrolidinyl)-phosphonium hexafluorophosphate
(PyOxim) as a coupling reagent under very dilute conditions. All structures were
analyzed by 1H and 13C NMR. With the structural similarities to the macrocyclic
peptides isolated from marine sources, this tetraoxazole macrocyclic peptide might be
used as a chelating agent
The effects of brief mindfulness induction and psychological stress manipulation on perceived stress
No full textThe effects of a brief mindfulness induction and psychological stress manipulation on perceived stress were studied using a sample of 51 Laurentian University Undergraduate Psychology students. Participants were subjected to either to a mindfulness manipulation condition (a focused attention task – an analogy of mindfulness induction – or a free mind wandering task), followed by a stress manipulation condition (either the Trier Social Stress Test (TSST) or an activity-matched placebo (TSSTp). Trait mindfulness (covariate), state mindfulness (manipulation check), perceived stress (manipulation check/dependant variable), and mood measures (dependant variable) were administered. Both mindfulness induction and stress induction manipulation checks were significant, indicating that participants understood the instructions, and the manipulations provided significant measured changes between groups. The stress manipulation check was significant in the expected direction, such that those in the stress experimental group rated as more stressed than the control group; however, the mood induction was significant opposite to expectations, such that the mind-wandering condition elicited significantly higher state mindfulness scores than the focused-breathing condition. There was no significant main effect of mindfulness on perceived stress scores, and contrary to the main hypothesis, there was no significant interaction between mindfulness condition and stress condition on perceived stress scores. Results of the mindfulness manipulation check suggest that the brief mindfulness manipulation utilized was not sufficient enough to produce measurable differences in mindfulness scores; however, the unexpected significance of the control group scores, coupled with a significant negative correlation between the trait and state mindfulness measures, may reflect discrepancies between the two measures of mindfulness and ultimately a difference between schools of mindfulness, or it may reflect an artifact of the methodology used.
The lack of significant results concerning mindfulness and perceived stress scores suggest that either 1) a brief 15-minute implementation of mindfulness may not be sufficient enough to buffer against immediate future stress, or 2) there were issues/confounding variables with the methodology used. There were no significant results concerning the mood measures. Results and future research are discussed
An integrated structural and geochemical study of auriferous sheeted quartz veins within the 2740 Ma Côté Gold deposit, Swayze Greenstone Belt, Ontario
No full textThe Archean Côté Gold deposit (8.3 M oz) is a low-grade, high-tonnage Au(-Cu) deposit located within the 2741 Ma Chester Intrusive Complex (CIC) on the southeast limb of the Swayze Greenstone Belt (SGB) in the Abitibi Subprovince of northern Ontario. Steeply-dipping, auriferous sheeted veins that form part of the mineralized setting can be interpreted as either orogenic in origin and associated with the formation of the proximal Ridout deformation zone or as older and intrusion-related. Structures that overprint CIC are similar to those of the RDZ and are interpreted to post-date the intrusion and mineralized veins. A geochemical study of an alteration profile related to a mineralized vein reveals elemental enrichment in K, Rb, Li, Cs, Ba, Na, F, S and LREEs with a Au-Cu-Te-Pb-Bi-S association. In situ SIMS analysis of δ34S and δ18O are consistent with a magmatic signature for the fluid with a minor component of seawater, and supports the previously proposed high-level, subaqueous setting for the deposit. The combination of temporal, spatial, and geochemical characteristics of the sheeted veins suggests an intrusion-related origin