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61.
62.
David J. Holloway 《Palaeontology》2004,47(4):1015-1036
The Monorakinae is a subfamily of the Pterygometopidae characterised by the fusion of L2 and L3 in the glabella. The resulting bicomposite lobe is expanded backwards to reach the occipital furrow, displacing L1 from contact with the axial furrow and causing the realignment of S1 to a markedly oblique orientation. The bicomposite lobe is commonly bounded adaxially by a longitudinal furrow containing three pairs of apodemal pits. The Monorakinae was probably derived from the Pterygometopinae, and includes the genera and subgenera Monorakos , Carinopyge , Ceratevenkaspis , Elasmaspis , Evenkaspis ( Evenkaspis ) and E . ( Parevenkaspis ), of which Carinopyge , Elasmaspis and Evenkaspis ( Parevenkaspis ) are known only from limited parts of the exoskeleton. Monorakines have a stratigraphical range of Caradoc–Ashgill. Their known geographical distribution in the Siberian Platform, Taimyr, the Russian Far East, and the Seward Peninsula of Alaska is restricted to areas that in the Ordovician were part of the palaeocontinents of Siberia and Arctida, which must have been connected or situated close together at that time. The occurrence of monorakines in the Taimyr Peninsula but their absence from Baltica does not support the suggestion of some workers that Taimyr was part of Baltica in the Ordovician. 相似文献
63.
Geiser F Holloway JC Körtner G 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2007,177(5):495-501
Most studies on animal physiology and behaviour are conducted in captivity without verification that data are representative
of free-ranging animals. We provide the first quantitative comparison of daily torpor, thermal biology and activity patterns,
conducted on two groups of sugar gliders (Petaurus breviceps, Marsupialia) exposed to similar thermal conditions, one in captivity and the other in the field. Our study shows that activity
in captive gliders in an outdoor aviary is restricted to the night and largely unaffected by weather, whereas free-ranging
gliders omit foraging on cold/wet nights and may also forage in the afternoon. Torpor occurrence in gliders was significantly
lower in captivity (8.4% after food deprivation; 1.1% for all observations) than in the field (25.9%), mean torpor bout duration
was shorter in captivity (6.9 h) than in the field (13.1 h), and mean body temperatures during torpor were higher in captivity
(25.3°C) than in the field (19.6°C). Moreover, normothermic body temperature as a function of air temperature differed between
captive and free-ranging gliders, with a >3°C difference at low air temperatures. Our comparison shows that activity patterns,
thermal physiology, use of torpor and patterns of torpor may differ substantially between the laboratory and field, and provides
further evidence that functional and behavioural data on captive individuals may not necessarily be representative of those
living in the wild. 相似文献
64.
Holloway GP Thrush AB Heigenhauser GJ Tandon NN Dyck DJ Bonen A Spriet LL 《American journal of physiology. Endocrinology and metabolism》2007,292(6):E1782-E1789
A reduction in fatty acid oxidation has been associated with lipid accumulation and insulin resistance in the skeletal muscle of obese individuals. We examined whether this decrease in fatty acid oxidation was attributable to a reduction in muscle mitochondrial content and/or a dysfunction in fatty acid oxidation within mitochondria obtained from skeletal muscle of age-matched, lean [body mass index (BMI) = 23.3 +/- 0.7 kg/m2] and obese women (BMI = 37.6 +/- 2.2 kg/m2). The mitochondrial marker enzymes citrate synthase (-34%), beta-hydroxyacyl-CoA dehydrogenase (-17%), and cytochrome c oxidase (-32%) were reduced (P < 0.05) in obese participants, indicating that mitochondrial content was diminished. Obesity did not alter the ability of isolated mitochondria to oxidize palmitate; however, fatty acid oxidation was reduced at the whole muscle level by 28% (P < 0.05) in the obese. Mitochondrial fatty acid translocase (FAT/CD36) did not differ in lean and obese individuals, but mitochondrial FAT/CD36 was correlated with mitochondrial fatty acid oxidation (r = 0.67, P < 0.05). We conclude that the reduction in fatty acid oxidation in obese individuals is attributable to a decrease in mitochondrial content, not to an intrinsic defect in the mitochondria obtained from skeletal muscle of obese individuals. In addition, it appears that mitochondrial FAT/CD36 may be involved in regulating fatty acid oxidation in human skeletal muscle. 相似文献
65.
Stauffer SR Stanton MG Gregro AR Steinbeiser MA Shaffer JR Nantermet PG Barrow JC Rittle KE Collusi D Espeseth AS Lai MT Pietrak BL Holloway MK McGaughey GB Munshi SK Hochman JH Simon AJ Selnick HG Graham SL Vacca JP 《Bioorganic & medicinal chemistry letters》2007,17(6):1788-1792
A series of low-molecular weight 2,6-diamino-isonicotinamide BACE-1 inhibitors containing an amine transition-state isostere were synthesized and shown to be highly potent in both enzymatic and cell-based assays. These inhibitors contain a trans-S,S-methyl cyclopropane P(3) which bind BACE-1 in a 10s-loop down conformation giving rise to highly potent compounds with favorable molecular weight and moderate to high susceptibility to P-glycoprotein (P-gp) efflux. 相似文献
66.
Katharine Holloway M McGaughey GB Coburn CA Stachel SJ Jones KG Stanton EL Gregro AR Lai MT Crouthamel MC Pietrak BL Munshi SK 《Bioorganic & medicinal chemistry letters》2007,17(3):823-827
Several simple scoring methods were examined for 2 series of beta-secretase (BACE-1) inhibitors to identify a docking/scoring protocol which could be used to design BACE-1 inhibitors in a drug discovery program. Both the PLP1 score and MMFFs interaction energy (E(inter)) performed as well or better than more computationally intensive methods for a set of substrate-based inhibitors, while the latter performed well for both sets of inhibitors. 相似文献
67.
Ritchie ME Silver J Oshlack A Holmes M Diyagama D Holloway A Smyth GK 《Bioinformatics (Oxford, England)》2007,23(20):2700-2707
MOTIVATION: Microarray data must be background corrected to remove the effects of non-specific binding or spatial heterogeneity across the array, but this practice typically causes other problems such as negative corrected intensities and high variability of low intensity log-ratios. Different estimators of background, and various model-based processing methods, are compared in this study in search of the best option for differential expression analyses of small microarray experiments. RESULTS: Using data where some independent truth in gene expression is known, eight different background correction alternatives are compared, in terms of precision and bias of the resulting gene expression measures, and in terms of their ability to detect differentially expressed genes as judged by two popular algorithms, SAM and limma eBayes. A new background processing method (normexp) is introduced which is based on a convolution model. The model-based correction methods are shown to be markedly superior to the usual practice of subtracting local background estimates. Methods which stabilize the variances of the log-ratios along the intensity range perform the best. The normexp+offset method is found to give the lowest false discovery rate overall, followed by morph and vsn. Like vsn, normexp is applicable to most types of two-colour microarray data. AVAILABILITY: The background correction methods compared in this article are available in the R package limma (Smyth, 2005) from http://www.bioconductor.org. SUPPLEMENTARY INFORMATION: Supplementary data are available from http://bioinf.wehi.edu.au/resources/webReferences.html. 相似文献
68.
69.
I‐Ching Chen Jane K. Hill Hau‐Jie Shiu Jeremy D. Holloway Suzan Benedick Vun Khen Chey Henry S. Barlow Chris D. Thomas 《Global Ecology and Biogeography》2011,20(1):34-45
Aim To estimate whether species have shifted at equal rates at their leading edges (cool boundaries) and trailing edges (warm boundaries) in response to climate change. We provide the first such evidence for tropical insects, here examining elevation shifts for the upper and lower boundaries shifts of montane moths. Threats to species on tropical mountains are considered. Location Mount Kinabalu, Sabah, Malaysia. Methods We surveyed Lepidoptera (Geometridae) on Mount Kinabalu in 2007, 42 years after the previous surveys in 1965. Changes in species upper and lower boundaries, elevational extents and range areas were assessed. We randomly subsampled the data to ensure comparable datasets between years. Estimated shifts were compared for endemic versus more widespread species, and for species that reached their range limits at different elevations. Results Species that reached their upper limits at 2500–2700 m (n= 28 species, 20% of those considered) retreated at both their lower and upper boundaries, and hence showed substantial average range contractions (?300 m in elevational extent and ?45 km2 in estimated range area). These declines may be associated with changes in cloud cover and the presence of ecological barriers (geological and vegetation transitions) which impede uphill movement. Other than this group, most species (n= 109, 80% of the species considered) expanded their upper boundaries upwards (by an average of 152 m) more than they retreated at their lower boundaries (77 m). Main conclusions Without constraints, leading margins shifted uphill faster than trailing margins retreated, such that many species increased their elevational extents. However, this did not result in increases in range area because the area of land available declines with increasing elevation. Species close to a major ecological/geological transition zone on the mountain flank declined in their range areas. Extinction risk may increase long before species reach the summit, even when undisturbed habitats are available. 相似文献
70.
Alessandro S Guimarães Filipe B Carmo Marcos B Heinemann Ricardo WD Portela Roberto Meyer Andrey P Lage Núbia Seyffert Anderson Miyoshi Vasco Azevedo Aurora MG Gouveia 《BMC veterinary research》2011,7(1):1-5