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Life-history trade-offs in Northern leopard frog (Lithobates [Rana] Pipiens) tadpoles: interactions of trace metals, temperature, and ranavirus
No full textEmerging infectious diseases, pollution and climate change are associated with amphibian extinction
events worldwide; however, direct causation is often obscured by the interactions of these stressors.
Elucidating the possible synergies between metal contamination and disease is, therefore, critical in
advancing our knowledge of the co-evolutionary mechanisms in host-pathogen systems and helping with
the ability to better forecast the spread of diseases in metal-stressed environments. Additionally,
increasing ecotoxicological research has improved our understanding of the complex influence trace
metals may have on the physico-chemical nature of aquatic systems; however, the discrepancy in
concentration-response within the toxicological literature makes it difficult to accurately define the range
of toxicity, often due to the variability in media used in experimentation. The first chapter of this thesis
reports an evaluation of copper, nickel and copper/nickel concentrations on several Northern Leopard
Frog (Lithobates [Rana] pipiens) larvae life history traits within field collected smelting effluent water.
Overall, results indicated that copper had a stronger negative impact on survival than nickel. However,
tadpoles exposed to copper displayed increased growth and developmental patterns while those exposed
to nickel demonstrated opposing life history traits. These results indicate that tadpoles are displaying
different fitness strategies, in terms of survival and life history, in the presence of increased copper and/or
nickel stress
Dark embrace: orestes complex, catathymic crisis and method of murder: a study of matricide in a forensic psychiatric sample
No full textA study was conducted to investigate and identify differences inherent in two subtypes of psychosis driven or mentally disordered homicide: matricide versus any other biological intrafamilial homicide or attempted homicide. Matricide was further investigated through the exploration of offence specific details, as well as demographic and diagnostic characteristics of persons who had committed (or attempted) homicide against the mother and were subsequently found not criminally responsible and detained by the Ontario Review Board between 1992 and 2012. Matricidal accused were more often diagnosed with childhood disorders and paranoid schizophrenia. As adults, they failed to mature sexually and socially, and continued to live at home, dependent on the mothers that were the ultimate victims of their violence. Attachment theory is offered as a proposed explanation for the matricidal impulse
