Summary
1.It is frequently asserted that the adaptation of metal tolerance involves a cost, i.e. tolerant individuals have a lowered fitness on uncontaminated soil. To date, however, evidence for a cost has been highly circumstantial. One well-known example of metal tolerance, copper tolerance in Mimulus guttatus, is used in this paper to search for a cost. 2. The absence of highly tolerant plants in the field, despite the ability to select, rapidly and artificially, for extreme levels of tolerance, indicates that strong selection against extreme tolerance occurs in this species. 3. Negative genetic correlations between plants selected for increased degree of tolerance and other fitness traits were sought to test the trade-off hypothesis that energy/resources needed to manifest tolerance are diverted away from other essential traits. 4. The case for using replicated selection lines when using this methodology to demonstrate a cost is put forward. It is argued that replication is required to show unambiguously that any correlations found result from the pleiotropic effects of the gene(s) that govern the adaptation and not the consequence of linkage disequilibrium.
5.No clear evidence to support the trade-off hypothesis was found.
This research involved interviewing three people who had experienced self-injury. They were accessed from the voluntary sector as I felt that if I had accessed them from the National Health Service their views might not be honest, due to their possible perceptions of threats to their care. It was not intended that the views of these people would be representative, my aim was that their views, as well as areas highlighted in the literature, would inform me of areas pertinent to the topic, when seeking staff views. The views of staff, of which there were 15 self-selecting clinicians, formed the main focus of the study. The aims of the research were designed to highlight potentially contrasting perceptions of self-injury as a means of illuminating a current clinical problem. The results showed that staff on the whole agreed with the perceptions of people who have experienced self-injury; that they are often viewed negatively, though this is changing. It was recognized that care was dependent on where the person entered the service. Staff recognized that the service is under pressure and provision may not be available in the voluntary sector for these clients.
Previous research into copper tolerance in the monkey flower Mimulus guttatus has found that: (i) it is primarily determined by a single dominant gene; and (ii) there is variation between tolerant plants that has been ascribed to 'modifiers'. Modifiers can be either nonspecific, which act additively on both tolerant (T) and nontolerant (NT) genotypes, or specific, which act only on the tolerant genotype, and are thus hypostatic to the tolerance locus. We show here that there are hypostatic modifiers of tolerance in this species. Two selection lines that differ in degree of tolerance (and thus in the presence of putative modifiers) were crossed to a single NT plant. The F 1 s were selfed to produce F 2 s that segregated 3:1 T:NT. NT F 2 individuals were crossed to a single homozygous T plant of low tolerance. The families differed in tolerance, showing that the NT F 2 individuals differed in genes that only have an effect on tolerance phenotype in the presence of the tolerance gene. F 3 individuals from F 2 s of contrasting phenotype were crossed to a second tester tolerant plant, and these F 3 s also varied, confirming the presence of the specific modifiers. There was no evidence of the segregation that would suggest a single modifier gene, but there is evidence from the F 2 s of at least one additive, nonspecific modifier in addition to the specific modifiers.
Clinical guidelines and research papers help clinicians measure and understand the risk of falling in their older clients but very few provide the assessor with recommendations as to which interventions they can use to reduce the risk of a fall. The Guide to Action for Falls Prevention tool (GtA) was developed to help professionals from a broad range of organizations to recognize factors that might increase falls risk and know which actions to take to lessen that risk. Twenty four professionals tested the GtA in a clinical setting and found it quick (15 minutes) and easy to complete. The GtA needs further evaluation to test whether it is a practical way of delivering a falls prevention intervention.
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