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Establishing a protocol for the measurement of human exposure to foot-transmitted vibration
No full textFoot-transmitted vibration (FTV) is defined as vibration exposure where the primary route of
vibration transmission is through the feet. Individuals can be exposed to FTV through a vibrating
platform that they stand on or from vibrating foot-operated controls. Workers exposed to FTV
are at risk of suffering from vibration white-foot, an irreversible disease with vascular,
neurological and musculoskeletal symptoms. In order to understand injury risk, the transmission
of vibration from a vibrating surface into the foot can be measured. The international standards
for the measurement of occupational vibration exposure (ISO 2631-1, 1997; ISO 5349-1, 2001)
do not provide appropriate guidance for FTV exposure measurement. Although several
researchers have reported worker exposure to FTV, the reliabilities of the methods used to
measure FTV have yet to be studied.
The purpose of this thesis is to propose a reliable protocol for the measurement of FTV exposure
(Vance FTV Measurement Protocol, V-FTVMP). Preliminary testing was conducted to examine
how factors such as location of accelerometer placement on the foot, changes in standing
posture, time of day that measurements are taken, and duration of measurement, influence
measures of FTV exposure. These findings were translated into the V-FTVMP. Inter-rater and
intra-rater reliability of the proposed method for the measurement of FTV transmissibility were
determined by testing the protocol with three raters and 12 participants. Transmissibility was
measured at the toe as the ratio of vibration input (measured on the platform) to vibration output
(measured on the surface of the toe), with values over one indicative of vibration amplification
and less than one indicative of attenuation. Transmissibility was also calculated as a ratio at the
ankle with input measured at the platform and output measured from the medial malleolus of the
iv
ankle. Mean un-weighted root-mean-squared (r.m.s.) accelerations (z-axis) for all accelerometer
locations were calculated for all participants and found to be 13.01 m/s2
(±0.87), 12.68 m/s2
(±1.19), 8.23 m/s2
(±2.24), and 16.05 m/s2
(±3.81) for measures at the platform at the toe,
platform at the ankle, toe at the first metatarsal head and ankle at the medial malleolus,
respectively. The mean transmissibility for all participants was measured as 0.63 (±0.16) at the
toe, and 1.27 (±0.30) at the ankle. The intraclass correlation tests showed good or acceptable
reliability for all locations: platform location at the toe ICC =.83 (CI =.67 -.92), platform at ankle
ICC =.82 (CI=.65-.92), toe ICC =.77 (CI =.37 -.81), ankle ICC =.60 (CI =.18 -.68). Based on the
results of this study, it appears the V-FTVMP can generate reliable measures of FTV. Additional
research led by independent groups is needed to confirm these results and to further validate the
protocol
Constraining alteration in the footwall of the Sudbury igneous complex: a case study of the alteration footprint to the Podolsky, Cu(-Ni)-PGE deposit, Sudbury
No full textThe footwall environment of the Sudbury Igneous Complex (SIC) host high-grade Cu-(Ni)-PGE
deposits that have become a prime exploration target due to increases in metal prices and
depletion of traditionally mined contact-style deposits that are high-grade Ni-Cu rich deposits.
Understanding and constraining footwall deposits has been underway for some time, still, several
aspects of these deposits that need to be constrained. With respect to alteration the nature, origin,
relevance, and significance of these hydrothermal minerals have not yet been constrained.
A detailed study of the homogeneous grey gabbro unit that is hosted in the Podolsky
2000 deposit host’s sharp-walled sulfide veins, rich in copper and PGEs was an ideal study area
to look at alteration leading up to sharp-walled sulfide veins and its association to mineralization
as the vein is approached. The initial step is to define and understand what the composition of the
least altered grey gabbro with respect to its petrogenetic, spatial, and chronological relationship.
Once the least altered grey gabbro is characterized alteration associated to these veins can be
explored in detail. Alteration assemblages associated to these sharp-walled veins could
potentially be implemented into an exploration tool for mining companies local to the area in
search of such footwall deposits. The least altered grey gabbro unit was not as homogenous as previously thought, after
careful review of petrography, SEM-DES, geochemical bulk-rock data, isotope work, and U-Pb
age dating; a suitable petrographic summary of the grey gabbro was achieved. Once a least
altered summary was achieved, comparing this data to transects leading up to these sharp-walled
sulfide veins and various samples of most altered grey gabbro were petrographically,
geochemically, isotopically, compared to the least altered samples available. Generally, understanding footwall deposits and unravelling the relevance and
significance of these hydrothermal minerals was summarized in this thesis, unfortunately, these
alteration trends are rather small and can only be observed <30 cm away from the vein, and are
most obvious against the vein. This indicated that alteration signatures are not very strong
outside of these sharp-walled sulfide veins, despite these veins ~1 m thick
L'analyse de l'expression de gènes associés à la résistance au nickel chez le chêne rouge (Quercus rubra) : effets moléculaires de la toxicité de différentes doses de nitrate de nickel
No full textLes objectifs principaux de cette étude étaient 1) de déterminer le niveau de toxicité du
nickel chez le chêne rouge (Quercus rubra), 2) d’évaluer la régulation des gènes associés à la
résistance au nickel chez les plantes de Q. rubra exposées à plusieurs doses de nickel et 3) de
déterminer l’expression des gènes impliqués dans la résistance au nickel chez les populations de
Q. rubra provenant de sites contaminés avec des métaux et de sites références de la Région du
Grand Sudbury (RGS). Plusieurs gènes associés à la résistance au Ni dans des plantes modèles et
non modèles ont été ciblés dans cette étude. Le PCR en temps réel (RT-qPCR) a été réalisé
suivant le protocole du fabricant. Nous n’avons observé aucun dommage ni de ralentissement de
croissance causés par le nickel sur les plantes qui ont été traitées avec différentes doses de nitrate
de nickel. L’expression des gènes Sérine AcétylTransférase (SAT) et Nicotianamine Synthase (NAS 3) ont été induites par le nickel dans les feuilles des plantes traitées avec 1600 mg/kg
comparées aux doses de 150 mg/kg et 800 mg/kg et les contrôles. Par contre, l’expression de
l’acide 1-aminocyclopropane-1-carboxylique désaminase (ACC désaminase) dans les feuilles a
été induite par le nitrate plutôt que le Ni lorsque les plantes étaient traitées avec 800 mg/kg
comparé aux témoins et autres doses. Aucune association n’a été établie entre l’expression de
NAS 3, SAT, ACC désaminase, Glutathion Réductase (GR), la protéine macrophage associé à la
résistance naturelle (NRAMP 3), la famille des protéines de transport à haute affinité
(AT2G16800) et la contamination par les métaux dans les populations naturelles de Q. rubra
dans la RGS. Ceci suggère que la quantité de métaux biodisponibles dans le sol n’est pas assez
suffisante pour affecter l’expression des gènes
The impact of childhood obesity discourses on domestic and reproductive labour for single mothers in Northeastern Ontario : an institutional ethnographic study
No full textRationale: The term “healthy children” is often used to describe children whose weights are within a socially acceptable range which conflates health with thinness, often completely overlooking other aspects of health and employing body-stigmatizing language about children. Research Questions: 1. How do single mothers who live in poverty in Northeastern Ontario define good health for their children? What role do considerations of obesity play in their definition of good health? 2. What are the implications of participants understanding of health on their domestic and reproductive labour? 3. How are these experiences mediated by the families’ social location? Theory: Institutional ethnography (IE) is a theory and a method. IE investigates the coordination of ideologies that shape people’s experiences. Institutions made up primarily of government bodies and medical experts shape how childhood obesity is discussed in schools, the media, and in everyday life, impacting how we understand and speak about children’s bodies. This includes the amount and types of work expected of parents (primarily mothers) as well as the implications for bodies that do not meet the standard deemed acceptable in a particular time and place. Method: The research participants were twenty women residing in Northeastern Ontario who self-identify as a single mother living in poverty. I used two methods of data collection: interviews and guided tours of key areas impacting children’s health, such as grocery stores or places children play. Analysis: I analysed the interviews and the interactions between participants and their environment using an institutional ethnographic approach to coding. The aim of the analysis is to link the everyday lived experiences of research participants to the ruling relations in which they are shaped. Results: Participants talked about children’s health in ways that were consistent with obesity discourses. When I asked what the term healthy child meant to them, the first response was usually ‘food’ followed by ‘physical activity’. Mothers described a great deal of work that went into trying to make decisions that they felt were healthy. However, they also described many barriers to providing the types of healthy foods and activities they would like to provide for their children
Eastern and Western mindfulness: investigating a potential mediating role of self-regulation
No full textThe present study examined the hypothesis that self-regulation of attention would
be the core mechanism that ties together two dominant conceptualizations of
mindfulness: (1) an eastern style more associated with influential figures such as Dr. Jon
Kabat-Zinn, and (2) a western style pioneered by Dr. Ellen Langer. Dispositional
mindfulness (defined as a trait rather than a momentary state of being) of eastern and
western styles as well as self-regulation were measured using self-reported
questionnaires: FFMQ, LMS and SRS. A large sample of participants (N=208), mostly
female university non-meditator students, completed the respective scales online. Selfregulation
of attention was correlated with both kinds of dispositional mindfulness. A
partial mediation effect of self-regulation of attention on eastern and western mindfulness
mode was revealed using the regression- based methods described by Baron and Kenny
(1986) and the Sobel-Goodman analyses. Implications and areas of future research are
discussed
Genomic insights into the psychrotrophic microbial leaching of low sulfide waste rock in kinetic testing systems
No full textThe microbial activity occurring within mine wastes is a known driver of the
development and perpetuation of acid generation from mining waste products, including waste
rock. The acid generating capacity of waste rock can pose a great environmental liability to
surrounding watersheds, which often prompts substantial management of large volumes of waste
rock throughout the development, operation, and closure of a mining operation. Kinetic testing
systems are a standard means of predicting the acid generating potential of waste rock, but are
dependent on abiotic or artificial biological amendments to measure this key parameter. Waste
rock from mine sites can be classified as potentially acid generating (PAG), which suggests
uncertainty around the acid generating status of the waste rock in question. Temperature is a key
control on the weathering of waste rock as the acceleration of abiotic and biotic sulfide oxidation
at warmer temperatures can induce faster weathering rates. Nonetheless, the relationship between
PAG rock geochemistry in colder regions and its native microbial communities have not been
well characterized in the field or in kinetic testing systems.
This thesis aims to address the microbial contribution to humidity cell and field leach bin
testing systems of low sulfur waste rock native to Boreal climate. A laboratory-based humidity
cell experiment was conducted over an extended 28 week period where the microbial community
was surveyed over time and compared to weekly leachate geochemistry. The same rock was
subjected to a field bin experiment, where the microbial community and leachate geochemistry
was profiled over 11 months. Both humidity cell and field bin experiments remained at near neutral conditions over the
course of the experiment and exhibited significant neutralization potential. The elemental release
rates differed between the humidity cell and field bin experiments, although all experiments
predicted the time to acid generation to be under 75 years. Temperature exerted a greater
influence on element release in the field bin experiments. Additionally, those elements in the
humidity cell experiments that exhibited significant differences in their release rates between
temperature treatments were not released at the same rates as they were in the field bin
experiments. Microbial communities in both experiments were analyzed through a combination
of 16S rRNA gene sequencing and shotgun metagenomics. The original, untreated, waste rock
from the mine site contained a microbial community dominated by sulfur oxidizers. After being
applied to field and laboratory scale leaching experiments, the initial microbial community
transitioned into communities unique to each experiment with clear shifts related to the duration
of the experiment and temperature treatments. Both field and laboratory experiments supported
microbial communities which were dominated by heterotrophs, with a less abundant community
of acidophilic chemolithotrophs that persisted from the initial rock community under warm and
cold temperatures. Metagenomic analysis also concluded that microogranisms living on the
waste rock have the capability to function in cool temperatures. The findings of this work present
a first glimpse into the microbial communities existing on low sulfide waste rock and how they
influence the behavior of kinetic testing systems at relevant seasonal temperatures
Characterization of metamorphic assemblages and assessment of Cu-Pb-Ag-Au-Zn mobility at the Lalor deposit, Snow Lake, Manitoba
No full textThe Lalor VMS deposit is located within the Snow Lake arc assemblage at the easternmost end
of the Paleoproterozoic Flin Flon belt. A regional metamorphic event at 1.81 Ga, up to middle
amphibolite facies (550˚C, 5kbar), recrystallized the mineral assemblages in the massive sulfide
and hydrothermally altered rocks that are associated with the formation of VMS deposits in the
area. The Lalor deposit differs from most VMS deposits in the area in that it contains low-sulfide
Au rich zones that are proximal to but separate from the massive sulfide lenses.
Gold mineralization primarily occurs in three rock types at the Lalor deposit: massive
sulfides, and calc-silicates to carbonate silicates, and Fe-Mg altered rocks. Electrum is the
dominant form of gold, but gold also occurs in sulfosalt phases such as aurostibite (AuSb2) and
in tellurides such as petzite (Ag3AuTe2). It is often associated with hessite (Ag2Te), altaite
(PbTe), chalcopyrite (CuFeS2), and galena (PbS). Gold mineralization occurs along fractures,
grain boundaries, cleavage planes, and as discrete inclusions in metamorphic minerals.
There are two dominant metal associations with gold: Cu-Au and Pb-Au. The Cu-Au
association is more common and occurs in a variety of rock types (including massive sulfides
and Fe-Mg altered rocks), whereas the Pb-Au association is restricted to calc-silicate to
carbonate silicate altered rocks.
In the massive sulfides, gold content and distribution are a function of primary VMS
zone refining processes; however, Au has been locally remobilized during metamorphism and
deformation. In the Fe-Mg altered rocks proximal to massive sulfide, the distribution and tenor
of Au reflects primary zone refining and local remobilization due to metamorphism and
deformation, whereas in Fe-Mg altered rocks distal to massive sulfide, gold distribution is
largely a product of pre-peak to peak metamorphic remobilization of primary VMS gold via
fluid-dominated transportation.
In the calc-silicate to carbonate silicate rocks, which contained or contain carbonate, Au
distribution reflects metamorphic remobilization. Metamorphic devolatilization of primary
carbonate bearing rocks is responsible for adding components such as H2O, CO2 and S2 into a
fluid phase that remobilized Au and some metals (e.g. Cu, Pb) in the deposit, and in altered rocks
located proximal and distal to the massive sulfide lenses. Gold was mobilized and transported as
a sulfur complex, with CO2 acting as a buffer for a low salinity fluid phase such that it could
maintain an elevated gold content for transport and deposition. The result of this mobilization is
responsible for the Pb-Au in calc-silicate to carbonate silicate altered rock
Critical incidents on the front-line: occupational health considerations for probation officers
No full textProbation officers (PO) are considered part of the broader criminal justice system and are
tasked with supervising offenders within a community setting. POs are guided by identified
deliverables of maintaining public safety, fostering offender rehabilitation, and ensuring
court ordered sanctions are enforced (Pitts, 2007). The organizational climate of probation
work requires these goals be achieved within the confines of increasing workload and
administrative demands, in conjunction with decreasing budgetary supports, coupled with a
changing offender population who are regarded as increasingly more high-risk and multineed (Gonzales, Schofield & Hart, 2005; Pitts, 2007). Probation work is considered a highrisk occupation (Gonzales et al., 2005; Parsonage & Bushey, 1987). POs are exposed to
direct trauma (Gonzales et al., 2005; Linder & Bonn, 1996; Lindner & Koehler, 1992;
Parsonage & Bushey, 1987; Rapp-Paglicci, 2004) and indirect trauma (Lewis, Lewis &
Garby, 2013; Severson & Pettus-Davis, 2011) within their workplace. Exposure to such
occupational hazards can result in negative psychological impacts for POs (Lewis et al.,
2012; Parsonage & Bushey, 1987). Front-line occupations such as police and fire services,
emergency response, military, and correctional work have been notably studied within the
research in relation to the occupational health risks associated with their employment
(McFarlane & Bryant, 2007; O’Donnell & Stephens, 2001), yet probation work remains
under investigated. This lack of knowledge about the contextual realities of probation work is
significant considering the potential psychological impacts of probation work as experienced
by POs (Gayman & Bradley 2013; Lewis et al., 2013; O’Donnell & Stephens, 2001;
Severson & Pettus-Davis, 2011). Through this research I focused on investigating mental
health outcomes for POs who have been exposed to a workplace critical incident (CI). The purpose of my study was to shed light on the phenomena of CIs and to better understand the
numerous complexities associated with this phenomenon. The intersection of PO exposure to
psychosocial occupational hazards and CIs and POs adaptations was investigated utilizing a
grounded theory methodology
Role of endogenous H2S in the attenuation of nickel-induced cell toxicity
No full textNickel as a heavy metal is known to bring threat to human health, and its exposure is associated
with changes in fibroblast activation which may contribute to its fibrotic properties. H2S has
recently emerged as an important gasotransmitter involved in numerous cellular signal
transduction and pathophysiological responses. Interaction of nickel and H2S on fibroblast cell
activation has not yet been studied. Here, we showed that low dose nickel (200 μM) induced the
activation of human fibroblast cells, as evidenced by 15% increase in cell growth, increased
migration and higher expression of α-smooth muscle actin (αSMA) and fibronectin, while high
dose of nickel (1 mM) inhibited cell viability. We further found that nickel repressed the mRNA
and protein expression of cystathionine gamma-lyase (CSE, a H2S-generating enzyme) and
blocked the endogenous production of H2S. Exogenously applied NaHS (a H2S donor) had no
effect on nickel-induced cell viability but significantly attenuated nickel-stimulated cell
migration and the expression of αSMA and fibronectin. In contrast, CSE deficiency deteriorated
nickel-induced αSMA expression. Moreover, H2S incubation reversed nickel-stimulated
TGFβ1/SMAD1 signal and blocked TGFβ1-initiated expressions of αSMA and fibronectin.
Nickel inhibited the binding of Sp1 with CSE promoter but strengthened the binding of Sp1 with
TGFβ1 promoter, which was reversed by exogenously applied NaHS. These data reveal that H2S
protects from nickel-stimulated fibroblast activation and the CSE/H2S system can be a potential
target for the treatment of tissue fibrosis induced by heavy metal
L’enseignement de l’attaque au volleyball en classe de terminale : cas des collèges du zou en république du Bénin.
Get PDF: In the setting of this survey we fixed ourselves like objective to show three (03) teachers of the EPS
the didactic transposition operated at the time of the attack of the volleyball in class of terminal and to compare
these didactic transpositions in order to clear gaps between the taught contents and those foreseen like being to
teach. To reach this objective we made recourse to certain key concepts of the theory of the antropology of the
didactic of Chevallard (1992). The essential results descended of our investigation revealed that the observed
teachers had put in work varied forms of attack. This diversity of convenient teaching observe could be bound to
reports personal and institutional of these teachers to the object to Know. In the same way to their personal
experience. However, gaps exist and acted as trampoline to remedy difficulties of pupils at the time of setting of
teaching/ learning and encourage and/ reinforce their level of motor cleverness acquirement. These positive
gaps give account of the personal report to the knowledge of teachers as well of their personal and professional experience