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Analysis of the American mink (Neovison vison) harvest decline and genetic introgression
No full textThe American mink (Neovison vison) is endemic to North America where they have been domesticated over the course of 150 years by the fur industry. These domestic mink have been escaping from farms around the world and in North America while the harvests of wild mink across Canada are in decline. In this thesis, I used a combination of environmental data, spatial data, and genetics to better understand the declines. A multiple linear regression and a tree regression indicated that muskrat harvest growth rate, road density, and annual precipitation had the most effect on the mink harvest. To study the genetic introgression of domestic and wild mink, a 300 basepair fragment of the mitochondrial control region was used to determine regional differences between the wild and domestic populations of Nova Scotia and Ontario. Color differences and the direction of introgression were also studied. Significant differences between Nova Scotia wild, Ontario wild, and domestic mink were found. A pairwise ɸst test was used to determine directional introgression and resulted in an introgression of the hybrids towards the wild population. Together these results provide a better understanding of the decline in mink harvest although further research is needed to assess the direct impact of domestic escapees on the environment and on the wild population in North America. Prevention of domestic escapees is needed to stop hybridization which is important for the preservation of the species and to prevent further risk of outbreeding depression
An interprofessional approach to trauma-informed care in the Mood and Anxiety program at Health Sciences North
No full textThe advanced practicum explored an interdisciplinary approach to trauma-informed care while working on an interprofessional health team in the Mood and Anxiety Program (MAP) at Health Sciences North in Sudbury, Ontario. The MAP team offers group-based therapy that is guided by evidence-based practices which include Cognitive Behavioural Therapy (CBT), mindfulness-based approaches and Dialectical Behavioural Therapy (DBT). Individual treatment is also offered to individuals with a diagnosis of Post-Traumatic Stress Disorder. The literature review analyzed the following key themes: CBT trauma treatment, DBT trauma treatment, trauma and substance abuse, interprofessional collaboration and narrative therapy trauma models. Entry-level social workers have little knowledge about working with PTSD and trauma exposure is often the driving force of many presenting issues for individuals struggling with mental health issues. Social work students need to be educated and have practical experience about trauma-informed care to be effective practitioners in the field of social work.Master of Social Wor
The impact of the CATCH early childhood program on young children’s physical activity, nutrition, and food behaviour
Get PDFInitially funded in 1988, the CATCH (Coordinated Approach To Child Health)
program is a school-based health promotion and childhood obesity prevention program. It
was designed to improve physical activity (PA) and healthy food choices in school-aged
children. The program has since expanded to include the CATCH Early Childhood
(CEC) program, developed for preschool-aged children (ages 3-5 years). The CEC
program incorporates preschool-based enhanced PA, nutrition, family educational
components, and staff learning materials in a health promotion program aimed at young
children. The program is one of the few interventions that includes nutrition, PA, and
family/staff components targeting young children (e.g. < 5 years). This thesis evaluated
the impact of CEC programming on young children’s nutrition behaviours, food
knowledge, and PA levels before and after implementation of the CEC program.
Registered Early Childhood Educators (RECEs) were trained and implemented the
program for 6-months. Our results demonstrated some significant findings relevant to
preschooler program development, but do not directly support the implementation of the
CEC program specifically. This study adds to the current body of literature around early
intervention programs within daycare settings, but further research is needed to quantify
whether all components of the CEC program can positively impact health outcomes (e.g.
nutritional choices and PA behaviours) among this cohort
Testing technosols over an ultramafic gradient for rehabilitation of diamond mine wastes in a subarctic region
Get PDFSubarctic regions are recognized as one of the largest remaining pristine landscapes on earth, but are currently experiencing progressive degradation due to human activity. Mining and site rehabilitation in northern regions can be challenging largely due to the remote location of these developments. Rehabilitation is often restricted to using local mine waste materials to construct technosols. This study focused on how mines in northern regions, specifically the isolated De Beers Victor Diamond Mine, can use local mineral mine waste material to manufacture successful soil covers. Specifically, our research focused on examining the performance and success of technosols across a gradient increasing in serpentine characteristics. The objectives of the study were to, (1) determine how technosols increasing in serpentine characteristics influence vegetation establishment and microbial activity, (2) determine how the quantity of peat influences vegetation establishment and microbial activity, and (3) determine how early physical and chemical characteristics, and early plant colonization on our technosols compare to a local natural environment undergoing primary succession. We constructed a factorial experiment on two areas of mine waste at the Victor Mine, the waste rock dumpsite, and a processed kimberlite storage facility. Three test blocks were constructed on each site comprising a total of 48 5 m x 5 m experimental plots with four mineral substrate mixtures, and two levels of peat application. Mixtures consisted of various combinations of coarse and fine processed kimberlite, a silty loam marine overburden, and 20% or 40% peat, creating a gradient with ultramafic, serpentine characteristics. Each plot was fertilized at a rate of 12.5 g m-2 (NPK 8-32-16), inoculated with a microbial inoculation ‘tea’ mixture, and seeded with a variety of native vegetation. Various early physical,
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chemical and biological characteristics were examined, including early plant colonization and microbial activity. To measure microbial activity, a 7-day aerobic soil incubation experiment was preformed in growth chambers, with and without the addition of glucose, where CO2 respiration rate was the only parameter examined. The results indicated that mixtures increasing in serpentine characteristics resulted in decreased vegetation establishment and microbial activity in the short-term, while the mixtures that were non-serpentine (100% overburden-peat) were the most successful for vegetation establishment and potentially short-term microbial activity. However, most differences between our mixtures were minor. Differences in quantity of peat were minor between our experimental mixtures, causing them to have no influence on the vegetation establishment between our mixtures, and only minor differences in microbial activity between our mixtures. Our technosols shared similar physical and chemical aspects with the early successional Attawapiskat River floodplain environment, and also shared similarities with a peat-overburden mixture currently being used to rehabilitate a stockpile at the Victor Mine. These early similarities could show their potential for success during mine rehabilitation. Our research provides insight into challenges associated with rehabilitation of subarctic environments and, in general, mine waste substrates. This research will provide the De Beers Victor Mine with suggestions for rehabilitation upon closure, and will provide them with information on challenges they may face if incorporating processed kimberlite into technosols
A investigation of the relationship between fracture type and force: blunt force trauma on mammalian juvenile ribs (Sus scrofa, linneaus)
No full textThe interpretation of bone trauma is an important aspect in understanding the
circumstances within a death investigation (1-3). Proper interpretation of fractures can aid in
identifying the number of blows, impact sites, the order in which they occur and the amount of
force required to inflict such wounds (1,2). Yet there is a paucity of research regarding the force
applied through the utilization of blunt implements used to inflict trauma. Such a study has the
potential of more accurately characterizing the trauma, with regard to the amount of force used to
create observed fracture patterns. In this preliminary study, a computer controlled impacting
machine was used to inflict direct trauma onto several full, semi-fleshed racks of juvenile pig
ribs (Sus scrofa, Linneaus) with a hammerhead attachment (n=36). Although there has been a
recent interest in fracturing devices (2, 4-6), this one differs in that it mimics the arching motion
of a human overhand swing, and is able to inflict trauma onto fully fleshed and intact specimens.
After each strike the force at the moment of impact was recorded and was later paired with its corresponding fracture. From there, the range of force associated with transverse, oblique, spiral,
greenstick, and comminuted fractures, as well as having no fractures at all were examined in
light of the recorded forces. Such results were compared to those of others performed prior to
work on the machine to determine if such relationships were consistent between studies. In this
study it was discovered that there is no threshold where one fracture group will start and another
will end
Comparison of the Biotage® RapidTrace® and Gilson® GX-271 ASPEC™ solid phase extraction automated liquid handler systems for drug screening applications in forensic casework
No full textInstrument operation and degree of carryover produced by the Biotage® RapidTrace® and the Gilson® GX-271 ASPEC™ solid-phase extraction liquid handler systems was compared. Samples of animal blood, human blood, and human serum were spiked with a high concentration mix of 10 drugs commonly encountered in forensic casework. They were extracted preceding three blank samples of corresponding matrix on both instruments and all samples were subsequently screened on an Ultra Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (UPLC-QTOF-MS) instrument to evaluate differences in drug response values. It was found that the GX-271 ASPEC™ instrument produced lower overall drug responses in blank samples and faster time to extinction of drug responses, thereby demonstrating improved control of carryover. This instrument also showed an improvement over the RapidTrace® in overall performance and ease of operation and is therefore recommended as a beneficial replacement.Submitted in Partial Fulfilment of the Course FORS 420
The role of renalase in catecholamine biosynthesis: a new protective mechanism against hypertension?
No full textRenalase is a secretory protein that may protect against hypertension by reducing levels of circulating catecholamines (CAs). Renalase knockout mice are hypertensive with elevated CA levels. There are no known physiological mechanisms that fully describe renalase’s influence on plasma CAs. The adrenal medulla is a major site for CA regulation, however, the role of renalase in this tissue has not been investigated. The purpose of this study was to determine a potential role of renalase in this tissue using three objectives: 1) Examine the regulation of renalase by signal activators of CA biosynthesis; 2) Determine the effects of renalase on the regulation of CA-biosynthesizing enzymes; 3) Examine the expression of renalase in hypertensive rats. For objective 1, renalase expression was analyzed in pheochromocytoma-derived PC12 cells after treatment with 10 signal activators (e.g. phorbol 12-myristate 13-acetate (PMA), forskolin, cobalt chloride (CoCl2), and dexamethasone (Dex)). For objective 2, PC12 cells were treated with recombinant renalase and mRNA levels of CA-biosynthesizing enzymes were quantitated. For objective 3, renalase expression was examined in adrenal glands from spontaneously hypertensive rats (SHRs) and compared with normotensive Wistar-Kyoto rats (WKYs). RT-PCR and western blotting were performed to quantify mRNA and protein levels. Three signal activators significantly altered renalase expression; changes in renalase expression were observed after PMA, CoCl2, and Dex treatment. Recombinant renalase treatment did not change the expression of CA-biosynthesizing enzymes. SHRs compared to WKYs had significantly higher levels of renalase mRNA, but not protein. Overall, this study is a first step to determine if renalase’s role in the adrenal medulla is to regulate CA biosynthesis and protect against hypertension
Characterization of barren and mineralized hydrothermal systems in an impact structure: the granophyre unit and footwall of the Sudbury Igneous Complex, Ontario, Canada
No full textThe Sudbury Igneous Complex (SIC) is the product of a differentiated impact melt sheet and one
of the best preserved impact sites globally. The top 1.5 km of the 2.5 km-thick crystallized melt
sheet, referred to as the granophyre unit (GR), exhibits strong textural, mineralogical,
geochemical, fluid inclusion, and oxygen isotopic evidence for a long and complex hydrothermal
history. This hydrothermal system has not previously been documented, and is characterized by
an early magmatic-hydrothermal stage that has been overprinted by a later hydrothermal stage.
The magmatic-hydrothermal stage was dominated by fluids exsolved from the GR and resulted
in pervasive saussuritization of plagioclase, alteration of alkali feldspar and plagioclase to endmember
compositions, and precipitation of epidote and muscovite in pits and void spaces. The
overprinting hydrothermal stage was dominated by modified seawater sourced from the
hydrothermal system in the overlying Onaping Formation and produced a pervasive alteration
assemblage characterized by epidote, ferro-actinolite, stilpnomelane, biotite, and titanite with
lesser muscovite, chlorite, and ferrotschermakite. The results from this study record a previously
unidentified complex and protracted post-crystallization history of fluid-rock interaction for the
GR that is related to the ore-forming hydrothermal system in the overlying Onaping Formation. The relationship between the hydrothermal system in the GR and the mineralized systems in the
footwall to the Sudbury Structure (SS) has not previously been established. The Nickel Rim
South (NRS) Cu-Ni-PGE deposit, located in the east range of the Sudbury Structure, Ontario,
records textural and geochemical evidence of a complex, multi-stage hydrothermal history and
provides an excellent comparison to the GR. Results from fluid inclusion petrography and
microthermometry are used in conjunction in order to characterize the hydrothermal system at NRS. The combined results of fluid inclusion petrography and microthermometry, evaporate
mound analysis, oxygen isotopic values of quartz, and trace element chemistry of alteration
minerals reveal a complex hydrothermal history at NRS related to the cooling SIC, which
contributed to hydrothermal remobilization of metals into the footwall. The hydrothermal fluids
are notably different from fluids documented in other mineralized footwall systems that are
represented by high temperature, multi-solid fluid inclusions inferred to be critical for ore
remobilization. Instead, the hydrothermal system at NRS shares more similarities with the GR
hydrothermal system, bringing into question the role of fluids represented by high temperature,
multi-solid inclusions in ore remobilization
Evolution of the Sudbury igneous complex southern metamorphic aureole and controls on anatexis
No full textThe South Range metamorphic aureole around the 1.85 Ga Sudbury Igneous Complex
(SIC) is spatiotemporally connected to the world-class ore deposits of the Sudbury
mining camp. Defining the physiochemical expression and understanding the evolution
of the metamorphic aureole are therefore of economic interest to mineral exploration
efforts. The importance of studying the SIC metamorphic aureole is highlighted by new
insights into low-P/high-T (LP-HT) metamorphism of basalts including, LP-HT mineral
assemblages, partial melting, melt mobilization, phase equilibria modelling of
metabasalts at relatively LP-HT conditions, element mobility during metamorphic
processes, and retrograde zircon formation with concurrent mobilization and fractionation
of Zr-Hf. The South Range metamorphic aureole is best preserved in Paleoproterozoic Elsie
Mountain Formation (EMF) metabasalts that form a large proportion of the immediate
footwall to the SIC along its southern margin, which also includes the Murray and
Creighton granites. Mapping of the metamorphic aureole in the EMF metabasalts defines
3 metamorphic zones: 1) an up to ca. 500 m wide pyroxene-hornfels zone (PHZ)
extending from the SIC contact and characterized by a peak metamorphic mineral
assemblage of plagioclase-clinopyroxene-orthopyroxene-magnetite-ilmenite estimated to
reflect peak temperatures of ≥925 °C; 2) a pyroxene-granofels zone (PGZ) extending
from the PHZ and up to 750 m from the SIC contact characterized by a similar twopyroxene
assemblage, but typically with abundant retrograde high-Ti hornblende; 3) a
hornblende-hornfels zone (HHZ) extending from the PGZ and to at least 1000 m from the SIC contact characterized by a hornblende-plagioclase-quartz-ilmenite ± biotite ± magnetite assemblage indicating temperatures of up to 680 °C. Field evidence for partial
melting and melt mobilization in the EMF metabasalts consist of mainly macroscopic
leucocratic patches that locally coalesce. Microtextural evidence for partial melting
includes optical continuous quartz domains containing plagioclase and pyroxenes locally
with euhedral crystal faces, and relatively low-Ca plagioclase and quartz frameworks
around mainly relatively high-Ca plagioclase representing nucleation from a melt onto
existing crystals. Phase equilibria modelling using bulk rock compositions indicate that
partial melting resulted in 10-20% melt generation in the PHZ, and probably even higher
degrees of melting is recorded locally. Compared to the granites where partial melts have
been traced as dikes for hundreds of meters injecting back into the SIC, no backinjections
were documented to emanate from the EMF metabasalts. This indicates that
while a high-T metamorphic aureole developed in the metabasalts, the granites were
continuously experiencing high degrees of partial melting preventing the development of
a metamorphic aureole even some time after solidification of the SIC. Thus, the width of
the high-T contact aureole is wider in the EMF metabasalts than in the granites. This is
also true in a comparison to the contact aureole documented in the North Range Archean
gneisses. Furthermore, the estimated peak contact metamorphic temperatures in the EMF metabasalts are in better agreement with previous thermal models that required
substantial thermomechanical erosion (800 m) of North Range footwall rocks to match
the width of the observed contact aureole. Thus, the process of thermomechanical erosion
might have been less significant in the EMF basalts and perhaps other mafic lithologies.
Trace element geochemistry of the EMF metabasalts successfully permits a
subdivision of the PHZ into Hornfels A and B zones. The Hornfels A zone defines the
metabasalts are in better agreement with previous thermal models that required
substantial thermomechanical erosion (800 m) of North Range footwall rocks to match
the width of the observed contact aureole. Thus, the process of thermomechanical erosion
might have been less significant in the EMF basalts and perhaps other mafic lithologies.
Trace element geochemistry of the EMF metabasalts successfully permits a
subdivision of the PHZ into Hornfels A and B zones. The Hornfels A zone defines the
inner most ca. 250 m, and is characterized by metabasalts that generally show relative
depletion in LILE, REE and HFSE. Thus, trace element systematics in the EMF
metabasalts of the Hornfels A zone accentuates the potential for metamorphic processes
including devolatilization reactions and partial melting to severely mobilizing not only
relatively easy mobilized elements, e.g., LILE, but also the relatively immobile HFSE.
Thus, the trace element systematics has the potential to identify high-T parts of the
metamorphic aureole where the micro- and macroscopic petrographic evidence has
subsequently experienced obliteration by tectonometamorphic events. The defining
geochemical characteristic of Hornfels A samples is a pronounced negative Zr-Hf
anomaly (Zr/Zr* < 0.67) that is associated with sub-chondritic Zr/Hf values. Furthermore,
zircon with uncharacteristic textures forming poikilitic, branching, and interstitial
networks are observed exclusively in Hornfels A samples, and yield an U-Pb age of 1850
± 24 Ma. The zircon textures, age, relation to high-T mineral assemblage, and chemistry
suggests crystallization from trapped melt films during retrograde cooling. In
combination with the whole rock trace element geochemistry these observations provides
strong circumstantial evidence that Zr-Hf was mobilized in silicate melts, and that a 250
m zone from the SIC contact experienced melt segregation. Important to mineral exploration efforts is the observation that the width
of the contact aureole in the EMF basalts appear to correlate with the thickness of the SIC
that is thought to have a primary control on the location of contact deposits. Also, the
width of the high-T contact aureole might provide a limiting factor for the extent to
which low-S Cu-PGE rich mineralization can penetrate into the footwall