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Modification of cellulose nanocrystals with quaternary ammonium-containing hyperbranched polyethylene ionomers by ionic assembly
No full textIn this article, we demonstrate the first surface modification of cellulose nanocrystals (CNCs) with quaternary ammonium-containing ionomers by ionic binding of their positively charged ammonium ions onto the negatively charged surface of CNCs. A range of hyperbranched polyethylene ionomers (I1–I6) having different ionic content (0.2–2.3 mol %) has been designed and employed for this purpose. The simple dropwise addition and mixing of the aqueous dispersion of CNCs with the ionomer solution in tetrahydrofuran (THF) conveniently renders the ionomer-modified CNCs (mCNC1–mCNC6). The presence of adsorbed ionomers on the modified CNCs is confirmed with spectroscopic and X-ray diffraction evidence and quantified through thermogravimetric analysis. The effects of the ionomer to CNC feed mass ratio and the ionomers of different ionic content on the modification have been examined. A study on the morphology of the modified CNCs by atomic force microscopy discloses the occurrence of side-to-side and/or end-to-end assembly of the CNC rods due to the “cross-linking” or bridging effects of the multidentate ionomers. Because of the hydrophobic hyperbranched polyethylene segments in the adsorbed ionomers, the modified CNCs can be dispersed in nonpolar or low-polarity organic solvents (such as THF, toluene, and chloroform). In particular, the THF dispersions of modified CNCs prepared with ionomers having ionic content ≥0.7 mol % (I3–I6) behave as thixotropic organo-gels at concentrations ≥40 mg mL–1. Further, the modified CNCs better disperse than unmodified CNCs in a hydrophobic ethylene–olefin copolymer (EOC) elastomer matrix and show better thermal stability than a surfactant-modified CNC sample. Tensile testing confirms that the EOC composites, filled with the ionomer-modified CNCs, are significantly reinforced with a tensile modulus nearly doubled that of neat EOC, and they demonstrate better elongation at break relative to those filled with unmodified CNCs or surfactant-modified CNCs.Natural Science and Engineering Research Council (NSERC) of Canad
Innovative technology and change management: E-health applications in Canada.
No full textBackground
Focusing on the Canadian healthcare system, this study explores factors influencing the adoption of recent specialized technology in e-health applications due to concerns about the allocation of economic resources and governmental policy formulation. This study focuses on the specific technologies of the Electronic Medical Record (EMR)-based-Personal Health Record (PHR) and their use by physicians and residents of Northern Ontario.
Objectives
The primary objective of this study is to understand the interdisciplinary factors that predict Northern residents’ attitude toward EMR-based-PHR innovative technology. Conducting this study also serves to increase awareness of patient-driven e-health in Northern Ontario and provides decision makers with useful quantitative data and strategies to support future initiatives.
Methods/Materials
Using customized data obtained from the National Physician Survey (NPS) in Canada and primary data collected through an adaptation of this survey, a comparative analysis was conducted to understand the electronic patient-physician relationship and explore interdisciplinary factors regarding perception and use of EMR-based-PHR. The data was analyzed using Descriptive Statistics, Z Test for two Population Proportions, ANOVA and Regression Analysis.
Results
The results indicate significant differences between Northern physicians and patients in usage and preference regarding several technological applications. More Northern patients use websites, social media and mobile applications than Northern physicians. In capturing health information, fewer physicians exclusively prefer to use electronic records than use a combination of paper charts and electronic records, and most Northern patients prefer either a combination of both methods or exclusively paper charts in their healthcare. Interdisciplinary factors related to EMR-based-PHR were significant predictors and explained 69.6% of the variance in the behavioral attitude and 74.5% of the variance in the behavioral intention to adopt this innovative technology.
Conclusions.
Establishing an electronic patient-physician relationship in the Canadian healthcare system requires coordinated and concerted efforts from all stakeholders involved in this process. Significant cost without benefits is evidence of a misallocation of Canadian resources and requires increased attention. New strategies must address current gaps in educational, technical, managerial, and financial supports. Physician support, however, is ultimately the key to increasing the adoption rate of EMR and fostering positive attitudes toward PHR among the Canadian people
The effect of teacher’s proxemic aspects on didactic relationship in swimming
No full textThis article is interesting in didactic distances (Forest, 2001) of two
Physical Education (PE) teachers of Swimming in Tunisia. Its objective is to
determine the different proxemic distances (Hall, 1966) of teachers at the
time of didactic regulation. We postulate that proxemic distances represent a
revealing of didactic relationship. The methodology of this research is
qualitative and clinic. It could be registered within the frame of clinic
didactic interactions of PE and on the clinic analysis of experimented and
novice teacher’s practice glimpsing “case by case” and to apprehend the
singular subject in didactics (Terrisse, 1999). Data collection and analysis are
organized according to the clinic didactic methodology. This temporal
methodology differs by three different times and crusaders. From
methodological point of view, this study limits itself to the second time
analysis, that of the test (Terrisse, 2000). We make the choice to focus on the
qualitative study of proxemic distances scale (Hall, 1966). Results put in
evidence that the practice of different proxemic modes by teachers have
effect on the didactic relationship
The identification and characterization of small molecules for the inhibition of NGF and proNGF8p75NTR interactions using surface plasmon resonance spectroscopy
No full text! The!survival!of!neurons!in!both!the!central!and!peripheral!nervous!systems!
depend!on!a!balance!between!pro8survival!and!pro8death!signaling!pathways.!
Neurotrophins!and!their!precursors,!proneurotrophins,!are!a!unique!family!of!
soluble!signaling!proteins,!which!act!to!preserve!this!balance.!Dysregulation!of!these!
proteins,!however,!has!been!implicated!in!several!pathologies.!Specifically,!both!
nerve!growth!factor!(NGF)!and!pro8nerve!growth!factor!(proNGF)!have!been!
implicated!in!the!development!and!progression!of!neurodegenerative!diseases,!such!
as!Parkinson’s!and!Alzheimer’s!diseases,!through!p75NTR8mediated!apoptotic!
signaling.!!Therefore,!the!identification!of!small!molecule!inhibitors!capable!of!
binding!to!and!modulating!NGF!and!proNGF!may!be!of!therapeutic!interest.!This!
thesis!aims!to!characterize!the!inhibitory!action!of!previously!reported!small!
molecule8based!NGF!inhibitors,!ALE80540,!PD90780,!Ro!0882750,!and!PQC!083,!as!
well!as!novel!derivatives!of!these!compounds,!using!surface!plasmon!resonance!
(SPR)!spectroscopy.!Of!the!established!inhibitors,!PD90780!offered!the!most!
effective!inhibitory!action!for!both!NGF!and!proNGF!binding!to!p75NTR,!suggesting!
that!this!compound!may!offer!multipotent!inhibition.!Further,!several!novel!ligand!
specific!molecules!were!identified,!which!selectively!inhibited!either!NGF!or!
proNGF8p75NTR!interactions.!Specifically,!BVNP!1,!BVNP!6,!and!BVNP!7!were!shown!
to!be!effective!inhibitors!of!NGF8p75NTR!interactions,!while!BVNP!3!and!BVNP!4!
were!found!to!be!selective!for!the!inhibition!of!proNGF!binding!to!p75NTR.!The!
findings!of!this!thesis!offer!new!insight!into!the!use!of!small!molecule!inhibitors!to!
! iv!
block!both!neurotrophin!and!proneurotrophin8mediated!signaling.!In!addition,!the!
compounds!described!herein!may!be!used!for!future!lead!development.
Anthropogenic effects on chronic stress and nest predation patterns in freshwater turtles
No full textHuman altered landscapes contribute to direct and indirect threats on wildlife populations. Chronically high stress, an indirect threat, has been associated with decreased fitness. I examined chronic stress in Midland Painted Turtles (Chrysemys picta marginata), Snapping Turtles (Chelydra serpentina), and Blanding's Turtles (Emydoidea blandingii) in areas with varying densities of anthropogenic structures in Muskoka,Ontario. Enzyme immunoassays were run, in partnership with Dr. Gabriela Mastromonaco (Toronto Zoo), on turtle claws to obtain concentrations of corticosterone (CORT). Most Snapping Turtles had above-minimum CORT, and male Midland Painted Turtles and Blanding's Turtles had relatively high CORT levels. Anthropogenic density did not seem to affect CORT levels, but more research needs to be done to understand the complex relationships. I also determined the rate and pattern of nest depredation, a direct threat, throughout egg incubation in areas of varying anthropogenic densities. Nest depredation occurred throughout egg incubation and relative nest mesopredator abundance did not differ among sites with varying anthropogenic densities. Contrary to some nest caging protocols, my findings suggest that nest cages should be kept on nests until the turtles hatch and priority should be given to caging nests in low road density areas to help increase population recruitment. Understanding indirect and direct threats to turtles can help inform mitigation strategies to improve their fitness
The effect of new drug exposure versus a drug free interval on prior drug resistance in ovarian cancer
No full textContinuous exposure of ovarian tumours to a chemotherapy drug can result in the acquisition of
drug resistance, which ultimately leads to chemotherapy failure and the death of a great majority
of ovarian cancer patients. While previous studies suggest that withdrawal of the chemotherapy
drug for a period of time (the drug-free interval) can result in restored clinical sensitivity to the
drug, it is unclear whether exposure to a new drug of contrasting mechanism of action may
accelerate restored sensitivity to the prior drug. In this study, we exposed a carboplatin-resistant
ovarian tumour cell line (A2780CBN) to increasing concentrations of docetaxel (A2780CBNDXL
cells) or we permitted the cells to grow in the absence of drug for an identical number of drug
passages (A2780CBNCC cells). Similarly, we exposed a docetaxel-resistant ovarian tumour cell
line (A2780DXL) to increasing concentrations of carboplatin (A2780DXLCBN cells) or we
permitted the cells to growth in the absence of drug for an identical period (A2780DXLCC cells).
By measuring the sensitivity of the above cell lines to either carboplatin or docetaxel, the aim of
my thesis studies was to compare the effects of a drug-free interval or the acquisition of new
drug resistance on prior drug resistance in vitro. The results showed that the prior carboplatin
resistance was not significantly altered by the acquisition of docetaxel resistance or by
withdrawal of carboplatin. However, prior docetaxel resistance was greatly reduced by selection
for carboplatin resistance or by prolonged docetaxel withdrawal. Microarray analysis suggests
that the loss of docetaxel resistance may be related to down-regulated expression of the ABCB1
and ABCB4 genes, which encode multidrug transporters. It may also relate to up-regulation of
CYP1B1 gene expression, which encodes cytochrome P450, a phase I enzyme involved in taxane
metabolism. The microarray analysis data also suggests that the newly established carboplatin
resistance in A2780DXLCBN cells may be related to the expression of genes that promote cell
survival by protecting cells from apoptotic death
Moosonee, Ontario: a model of cold war change
No full textConsiderable research has been conducted on the Canadian north over the past few
decades. This research has focused on resource development (mining and forestry), on small
resource towns, and on mega-projects such as the James Bay Hydro Project. To date, little work
has been produced on the relationship between military activity in the north and the landscapes,
communities and people affected by such activity.
This study examines the impact of the Cold War on the community of Moosonee,
Ontario. By the mid-1950s Moosonee had become a shipping centre for northerly radar base
developments. Further growth occurred as a result of the construction and operation of a Royal
Canadian Air Force (RCAF) radar base adjacent to Moosonee from 1961 to 1975. Moosonee
adapted to two types of development: population growth generated by military construction and
activity, and redevelopment initiated by the closure of the RCAF base. Community adaptation to
growth included major changes to local infrastructure and the evolution of local government.
Once the radar base closed, the town’s residents seized the opportunity to use the housing and
infrastructure on the RCAF base to fill local needs. Furthermore, local people worked with
neighbouring communities to ensure that the RCAF base was transformed into a regional high
school. The initial purpose of this study was twofold: to understand the impact of military
development by examining how Moosonee changed from 1955 to 1975, and to report back to the
residents of Moosonee on research results. Near the conclusion of the interviews and data
collection stage it became clear that the broader purpose of this study was to join the
conversation on community development models and to develop a model which fit the
Moosonee experience. The thesis concludes with an explanation of the stages of development in Moosonee as compared to theoretical development stages, the impacts of the Cold War, and the
way that impacts varied depending on the social status of individuals. It also demonstrates how
Moosonee’s residents transformed community planning from provincially driven to local citizen-driven
planning
The roots of contemporary adolescent mental health an Erikson perspective
No full textThis theoretical thesis was inspired by this social workers desire to have a
better understanding of the increase in self-harming behaviours, including suicidal
ideation, depression, and anxiety among today’s youth. Why all these complex and
multi systemic breakdowns.
The approached was interdisciplinary in nature which included biological,
social, philosophical, anthropological, psychological, and developmental aspects of
the individual. When considering a platform, the decision was made to use Erikson’s
theory of psychosocial developmental as it provided the broad contextual framework
in understanding the fundamental requirements of acquiring a healthy identity
through various psychosocial stages.
The research analyzed an array of factors such as family structure, parenting
styles, relationships, culture, practices, self-determination, materialism/consumerism
along with other social determinants and how all of them having some degree of
influence on an adolescent’s inability to achieve a healthy identity formation.
The intent is not to provide the reader with any direct approaches or strategies to reducing adolescent mental health issues but offers a critical and comprehensive
understanding of the multitude of elements that contribute to an adolescent’s state of
disequilibrium and potential avenues to explore in therapy.Maîtrise en Service Socia
Characterization of banded iron formations associated with gold mineralization: primary geochemical signatures and exploration implications
No full textAlgoma-type banded iron formations (BIFs), which represent chemical sedimentary rocks characterized by alternating layers of iron-rich minerals and chert intercalated with Eoarchean to late Paleoproterozoic volcano-sedimentary sequences, act as a favorable host rock for orogenic gold mineralization within several Archean cratons (i.e., Pilbara, Kaapvaal, Superior, Slave and Churchill). Besides this economic aspect, these Fe-rich sequences have long been appreciated as an important contributor to furthering our understanding of the geochemical evolution of the Earth. However, these deposits are in general tectonically deformed, metamorphosed and dismembered, thus making reconstruction of their depositional setting and overall geologic setting difficult.
Based on four Canadian BIF-hosted gold deposits (the Meadowbank, Meliadine, Musselwhite and Beardmore-Geraldton deposits), this thesis aims to establish the depositional setting of the Algoma-type BIF using the abundance of REE+Y of chert material used as proxy of the primary signature, as well as assess gold enrichment processes based on textures and trace element zoning of variable sulfides (i.e., pyrite, arsenopyrite and pyrrhotite) and finally study if there is a particular geochemical type of Algoma-type BIF associated with gold mineralization.
Laser ablation-inductively coupled plasma-mass spectrometric (LA-ICP-MS) analyses performed on chert material suggest that BIFs from the four deposits show common depositional settings illustrated by deposition in semi-closed to closed basin under variable influence of high-temperature (>250ºC) hydrothermal fluids input and detrital contamination. Moreover, evidence of late diagenetic processes involving O isotopic exchange between chert precursor (i.e., opaline material) and seawater origined fluid have been documented. According to their primary
v
signature, it appears that barren versus mineralized BIFs do not show any geochemical divergence suggesting that the depositional setting may influence the epigenetic gold mineralization. Based on quantitative element distribution maps combined with line traverse and spot analyses by LA-ICP-MS on sulfides, a common gold mineralizing event characterized by intense stratabound sulfide-replacement of Fe-rich material was reported in three studied deposits exhibiting a Au-As-Se-Te-Ag element association. This result suggests that metamorphic/hydrothermal orogenic processes driven by devolatilization of a common weakly to unmetamorphosed source rock have ledto generation of gold-bearing fluid which channelled into Algoma-type BIF via major crustal faults and/or shear zones within low tensile strength rock
Product placement in House of Cards: the effects of mode of presentation and prominence on memory
No full textProduct placement refers to the inclusion of commercial products in noncommercial
settings. Research has typically focuses on attempting to determine what
characteristics make a product placement more effective and is often measured by
explicit memory of the brands presented. Previous studies have had issues with
generalizability due to the lack of an objective and consistent use of an operational
definition for factors such as prominence. This study aims at validating a coding system
developed by Concave Brand Tracking, which established and operationally defined five
levels of visual prominence. This study measures explicit memory for each of the five
levels of visual prominence with the hypothesis that, as level of prominence increases the
memory of the exposure to the brand would increase as well. The results of the
experiment support this hypothesis. The effects of presentation mode (i.e. audio or visual)
on memory were also investigated. The hypothesis based on the theory of dual coding
was, when a product has both an audio and visual presentation, memory is improved
compared to a product placement using a single presentation mode. This hypothesis was
also supported by the results of the experiment. Overall this study suggests both mode of
presentation and level of prominence have an impact on viewer’s ability to accurately
remember exposure to product placement within the Netflix series House of Card