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71.
On efficient probability forecasting systems 总被引:1,自引:0,他引:1
72.
73.
Caron D Coughlan AP Simard M Bernier J Piché Y Chênevert R 《Biotechnology letters》2005,27(10):713-716
Reduction of acetophenone by Daucus carota hairy root cultures afforded (S)-phenylethanol in high yield (96%) and excellent enantiomeric excess (ee ≥ 98%). Aromatic ketones, keto esters, and a simple aliphatic ketone were reduced with good stereoselectivity (ee = 62–98%) and moderate to high chemical yields (25–90%). 相似文献
74.
Protein conformational diseases arise when a cellular protein adopts an aberrant shape that either directly or indirectly
alters the physiology of its host cell. Notable conformational diseases include cystic fibrosis, Huntington’s disease, the
prion-related diseases, Alzheimer’s disease, and antitrypsin deficiency. In principle, the severity and progression of conformational
diseases can be altered by cellular factors that recognize and attempt to ameliorate the harmful effects of the disease-causing,
misshapen protein. To better define the mechanistic underpinnings of cellular factors that mediate quality control, and to
understand why a single misfolded protein can impact cell viability, specific proteins that cause each of the diseases listed
above have been expressed in a model eukaryote, the yeast Saccharomyces cerevisiae. In this review, we describe what has been learned from these studies, and speculate on future uses of yeast expression systems. 相似文献
75.
Kimberly A. Coughlan Thomas W. Balon Rudy J. Valentine Robert Petrocelli Vera Schultz Amanda Brandon Gregory J. Cooney Edward W. Kraegen Neil B. Ruderman Asish K. Saha 《PloS one》2015,10(5)
We have previously shown that incubation for 1h with excess glucose or leucine causes insulin resistance in rat extensor digitorum longus (EDL) muscle by inhibiting AMP-activated protein kinase (AMPK). To examine the events that precede and follow these changes, studies were performed in rat EDL incubated with elevated levels of glucose or leucine for 30min-2h. Incubation in high glucose (25mM) or leucine (100μM) significantly diminished AMPK activity by 50% within 30min, with further decreases occurring at 1 and 2h. The initial decrease in activity at 30min coincided with a significant increase in muscle glycogen. The subsequent decreases at 1h were accompanied by phosphorylation of αAMPK at Ser485/491, and at 2h by decreased SIRT1 expression and increased PP2A activity, all of which have previously been shown to diminish AMPK activity. Glucose infusion in vivo, which caused several fold increases in plasma glucose and insulin, produced similar changes but with different timing. Thus, the initial decrease in AMPK activity observed at 3h was associated with changes in Ser485/491 phosphorylation and SIRT1 expression and increased PP2A activity was a later event. These findings suggest that both ex vivo and in vivo, multiple factors contribute to fuel-induced decreases in AMPK activity in skeletal muscle and the insulin resistance that accompanies it. 相似文献
76.
J. Carlsson D. T. Gauthier J. E. L. Carlsson J. P. Coughlan E. Dillane R. D. Fitzgerald U. Keating P. McGinnity L. Mirimin T. F. Cross 《Journal of fish biology》2013,82(3):944-958
By combining next‐generation sequencing technology (454) and reduced representation library (RRL) construction, the rapid and economical isolation of over 25 000 potential single‐nucleotide polymorphisms (SNP) and >6000 putative microsatellite loci from c. 2% of the genome of the non‐model teleost, Atlantic cod Gadus morhua from the Celtic Sea, south of Ireland, was demonstrated. A small‐scale validation of markers indicated that 80% (11 of 14) of SNP loci and 40% (6 of 15) of the microsatellite loci could be amplified and showed variability. The results clearly show that small‐scale next‐generation sequencing of RRL genomes is an economical and rapid approach for simultaneous SNP and microsatellite discovery that is applicable to any species. The low cost and relatively small investment in time allows for positive exploitation of ascertainment bias to design markers applicable to specific populations and study questions. 相似文献
77.
S. J. Painting J. van der Molen E. R. Parker C. Coughlan S. Birchenough S. Bolam J. N. Aldridge R. M. Forster N. Greenwood 《Biogeochemistry》2013,113(1-3):237-257
A conceptual model of the main carbon and nitrogen flows through pelagic and benthic food webs was used to identify the key biogeochemical processes representing ecosystem functioning, and to select indicators of each of these processes. A combined fieldwork and modelling approach was used to provide the data required to evaluate the indicators in terms of their suitability for assessing and managing the impacts of climate change and demersal trawling. Four of our 16 proposed indicators (phytoplankton production and productivity, near-bed oxygen concentrations and oxygen penetration of the seabed) met the majority of criteria we used for evaluating indicators. Five indicators (depth of anoxic sediment, zoobenthos biomass, production, productivity and bioturbation potential) did not comply with sufficient criteria to be considered as good indicators. Six of our proposed indicators (zooplankton biomass, size structure, production and productivity; ecosystem productivity; ecosystem balance) could not be assessed for sensitivity and specificity using our models, and therefore need to be addressed in future work aimed at improving both the models and the fieldwork. Our results indicate that evaluation of indicators is difficult, because of the number and variety of human pressures which need to be considered in reality, and the interactions between these pressures and the ecosystem components which they affect. The challenge will be to establish if there are indeed any indicators which are able to meet the majority of criteria for good indicators in holistic ecosystem-based assessments. 相似文献
78.
Ross Finlay Russell Poole Jamie Coughlan Karl P. Phillips Paulo Prodhl Deirdre Cotter Philip McGinnity Thomas E. Reed 《Ecology and evolution》2020,10(4):1762-1783
The degree of natal philopatry relative to natal dispersal in animal populations has important demographic and genetic consequences and often varies substantially within species. In salmonid fishes, lakes have been shown to have a strong influence on dispersal and gene flow within catchments; for example, populations spawning in inflow streams are often reproductively isolated and genetically distinct from those spawning in relatively distant outflow streams. Less is known, however, regarding the level of philopatry and genetic differentiation occurring at microgeographic scales, for example, where inflow and outflow streams are separated by very small expanses of lake habitat. Here, we investigated the interplay between genetic differentiation and fine‐scale spawning movements of brown trout between their lake‐feeding habitat and two spawning streams (one inflow, one outflow, separated by <100 m of lake habitat). Most (69.2%) of the lake‐tagged trout subsequently detected during the spawning period were recorded in just one of the two streams, consistent with natal fidelity, while the remainder were detected in both streams, creating an opportunity for these individuals to spawn in both natal and non‐natal streams. The latter behavior was supported by genetic sibship analysis, which revealed several half‐sibling dyads containing one individual that was sampled as a fry in the outflow and another that was sampled as fry in the inflow. Genetic clustering analyses in conjunction with telemetry data suggested that asymmetrical dispersal patterns were occurring, with natal fidelity being more common among individuals originating from the outflow than the inflow stream. This was corroborated by Bayesian analysis of gene flow, which indicated significantly higher rates of gene flow from the inflow into the outflow than vice versa. Collectively, these results reveal how a combination of telemetry and genetics can identify distinct reproductive behaviors and associated asymmetries in natal dispersal that produce subtle, but nonetheless biologically relevant, population structuring at microgeographic scales. 相似文献
79.
Natural selection acts on Atlantic salmon major histocompatibility (MH) variability in the wild 总被引:4,自引:0,他引:4
de Eyto E McGinnity P Consuegra S Coughlan J Tufto J Farrell K Megens HJ Jordan W Cross T Stet RJ 《Proceedings. Biological sciences / The Royal Society》2007,274(1611):861-869
Pathogen-driven balancing selection is thought to maintain polymorphism in major histocompatibility (MH) genes. However, there have been few empirical demonstrations of selection acting on MH loci in natural populations. To determine whether natural selection on MH genes has fitness consequences for wild Atlantic salmon in natural conditions, we compared observed genotype frequencies of Atlantic salmon (Salmo salar) surviving in a river six months after their introduction as eggs with frequencies expected from parental crosses. We found significant differences between expected and observed genotype frequencies at the MH class II alpha locus, but not at a MH class I-linked microsatellite or at seven non-MH-linked microsatellite loci. We therefore conclude that selection at the MH class II alpha locus was a result of disease-mediated natural selection, rather than any demographic event. We also show that survival was associated with additive allelic effects at the MH class II alpha locus. Our results have implications for both the conservation of wild salmon stocks and the management of disease in hatchery fish. We conclude that natural or hatchery populations have the best chance of dealing with episodic and variable disease challenges if MH genetic variation is preserved both within and among populations. 相似文献
80.
Phillip C. Watts David O’Leary Mary C. Cross Jamie Coughlan Eileen Dillane Suzanne M. Kay Suzanne Wylde René Stet Richard D. M. Nash Emma M. C. Hatfield Thomas F. Cross 《Hydrobiologia》2008,606(1):27-33
Porifera is a primarily marine phylum comprising more than 15,000 species. The successful and wide adaptive radiation of freshwater
sponges (Haplosclerida: Spongillina) has resulted in the colonization of an extremely wide variety of habitats at all latitudes.
Colonization is dated back to the Mesozoic, and the mono- or poly-phyletism of Spongillina, and the number of potential sponge
invasions into freshwater is still under debate. Living freshwater sponges belong to 45 genera in six families for a total
of 219 species. The highest diversity, at the scale of zoogeographic regions, is recorded from the Neotropical (65 species),
Palaearctic (59 species), and Afrotropical regions (49 species). Endemic freshwater sponge species are 103 (47%) out of 219.
All species belonging to the families Lubomirskiidae, Metschnikowiidae, and Malawispongiidae are endemic. Endemic species
among the other families are 72% for Potamolepidae, 38% for Spongillidae, and 32% for Metaniidae. Data on some wide geographic
areas are scattered and fragmentary if not almost completely lacking. Species richness is probably underestimated and doubtless
destined to increase with further research.
Guest editors: E. V. Balian, C. Lévêque, H. Segers & K. Martens
Freshwater Animal Diversity Assessment 相似文献