Long term follow up after surgery in congenitally corrected transposition of the great arteries with a right ventricle in the systemic circulation

Aim of the study: To investigate the long-term outcome of surgical treatment for congenitally corrected transposition of the great arteries (CCTGA), in patients with biventricular repair with the right ventricle as systemic ventricle.Methods: A total of 32 patients with CCTGA were operated between January 1972 and October 2008. These operations comprised 18 patients with a repair with a normal left ventricular outflow tract, 11 patients with a Rastelli repair of the left ventricle to the pulmonary artery and 3 patients with a cardiac transplantation.Results: Excluding the cardiac transplantation patients, mean age at operation was 16 years (sd 15 years, range 1 week - 49 years). Median follow-up was 12 years (sd 10 years, range 7 days - 32 years). Survival obtained from Kaplan-Meier analysis at 20 years after surgery was 63% (CI 53-73%). For the non-Rastelli group these data at 20 years were

Managed Metapopulations: Do Salmon Hatchery ‘Sources’ Lead to In-River ‘Sinks’ in Conservation?

Maintaining viable populations of salmon in the wild is a primary goal for many conservation and recovery programs. The frequency and extent of connectivity among natal sources defines the demographic and genetic boundaries of a population. Yet, the role that immigration of hatchery-produced adults may play in altering population dynamics and fitness of natural populations remains largely unquantified. Quantifying, whether natural populations are self-sustaining, functions as sources (population growth rate in the absence of dispersal, λ>1), or as sinks (λ<1) can be obscured by an inability to identify immigrants. In this study we use a new isotopic approach to demonstrate that a natural spawning population of Chinook salmon, (Oncorhynchus tshawytscha) considered relatively healthy, represents a sink population when the contribution of hatchery immigrants is taken into consideration. We retrieved sulfur isotopes (34S/32S, referred to as δ34S) in adult Chinook salmon otoliths (ear bones) that were deposited during their early life history as juveniles to determine whether individuals were produced in hatcheries or naturally in rivers. Our results show that only 10.3% (CI = 5.5 to 18.1%) of adults spawning in the river had otolith δ34S values less than 8.5‰, which is characteristic of naturally produced salmon. When considering the total return to the watershed (total fish in river and hatchery), we estimate that 90.7 to 99.3% (CI) of returning adults were produced in a hatchery (best estimate = 95.9%). When population growth rate of the natural population was modeled to account for the contribution of previously unidentified hatchery immigrants, we found that hatchery-produced fish caused the false appearance of positive population growth. These findings highlight the potential dangers in ignoring source-sink dynamics in recovering natural populations, and question the extent to which declines in natural salmon populations are undetected by monitoring programs

AVONET: morphological, ecological and geographical data for all birds

Functional traits offer a rich quantitative framework for developing and testing theories in evolutionary biology, ecology and ecosystem science. However, the potential of functional traits to drive theoretical advances and refine models of global change can only be fully realised when species‐level information is complete. Here we present the AVONET dataset containing comprehensive functional trait data for all birds, including six ecological variables, 11 continuous morphological traits, and information on range size and location. Raw morphological measurements are presented from 90,020 individuals of 11,009 extant bird species sampled from 181 countries. These data are also summarised as species averages in three taxonomic formats, allowing integration with a global phylogeny, geographical range maps, IUCN Red List data and the eBird citizen science database. The AVONET dataset provides the most detailed picture of continuous trait variation for any major radiation of organisms, offering a global template for testing hypotheses and exploring the evolutionary origins, structure and functioning of biodiversity

An investigation into the asymmetric synthesis of novel benzopyrans for biological evaluation

The aim of this project was to prepare a novel range of dicobalt hexacarbonyl-alkyne complexes for testing as anticancer agents and benzopyrans as antihypertensives. In addition an investigating into the stereoselectivity of the Nicholas reaction will be undetaken. Hypertension and cancer are two very different dieases that are becoming more prevalent in modern life. Interest in antiproliferatory compounds containing metallic substituents has intensified since the serendipitous discovery of cisplatin in 1969. More recently Co-ASS, a dicobalt hexacarbonyl alkyne complex derived from aspirin, was found to out perform Cisplatin in the inhibition of MCF-7 breast cancer cells. This has led to a number of cobalt-alkyne complexes being found to possess anticancer activity. The preparation of a range novel cobalt-alkyne complexes is herein described along with the testing of their efficacy against CaCo-2 cancer cells. This Study showed that the presence of aromatic ring substituents had a large detrimental effect on their activity with the unsubstituted counterpart eliciting an IC50 value of 16.02 µM relative to >100 µM for the substituted counterparts. The observed IC50 of 16.02 is similar to those found in the literature for the cobalt-alkyne complexes of propargyl amides Co-ASSAM and Co-Phthal giving values of 8.8 and 22.2 repectively on MCF-7 cells. Benzopyrans are known to relax smooth muscle by activating transmembrane potassium channels. Cromakalim, the bench mark potassium channel activator however is not used clinically due to undesirable side effects. This has led to a large amount of work into the preparation of novel benzopyrans that maintain this activity whilst eliminating these side effects. Although the novel benzopyrans prepared were shown to be less active, as vasorelaxants, compared to cromakalim, they do, show greater activity compared to compounds that had been previously prepared within the Tyrrell group. Finally we show the exclusive cis diastereoselective nature of our studied Nicholas reaction in the simultaneous formation of two chiral centres. The effect of chiral induction on the formation of these two centres is also investigated showing the ee of the Nicholas reaction to be >99% and a de of 68% in the most selective instance

Attention to overlapping objects: detection and discrimination of luminance changes

Selective attention to 1 of 2 overlapping objects was assessed in a cuing paradigm. Participants detected or identified targets that appeared in 1 of 6 possible target locations (3 on each object). Significant cuing effects for the simple detection of such targets using both reaction time and sensitivity measures of performance were found. Cuing effects were consistently greater when the participants were required to identify some aspect of the target even when the tasks (detection vs. identification) were equated for overall performance level. These differences in cuing effects between tasks were much reduced if the target locations were no longer grouped into 2 objects. It is suggested that identical stimuli can elicit differing attentional mechanisms depending on task type (rather than task difficulty) and that these mechanisms differ in the nature of the representation of the visual world