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61.
R W Gauldie D A Fournier D E Dunlop G Coote 《Comparative biochemistry and physiology. A, Comparative physiology》1986,84(4):607-615
Atomic emission experiments on whole otoliths of the chinook salmon (Oncorhynchus tshawytcha) show that a statistically significant relationship exists between otolith ion content (Fr, Zn, Mn, Na, Sr, P), ambient temperature, body length and otolith weight amongst individuals maintained under controlled diet and water conditions. Direct proton microprobe studies confirm these results and suggest that it may be possible to recover the temperature life history of individual fishes from the otolith. 相似文献
62.
Background
Camouflage patterns that hinder detection and/or recognition by antagonists are widely studied in both human and animal contexts. Patterns of contrasting stripes that purportedly degrade an observer's ability to judge the speed and direction of moving prey ('motion dazzle') are, however, rarely investigated. This is despite motion dazzle having been fundamental to the appearance of warships in both world wars and often postulated as the selective agent leading to repeated patterns on many animals (such as zebra and many fish, snake, and invertebrate species). Such patterns often appear conspicuous, suggesting that protection while moving by motion dazzle might impair camouflage when stationary. However, the relationship between motion dazzle and camouflage is unclear because disruptive camouflage relies on high-contrast markings. In this study, we used a computer game with human subjects detecting and capturing either moving or stationary targets with different patterns, in order to provide the first empirical exploration of the interaction of these two protective coloration mechanisms.Results
Moving targets with stripes were caught significantly less often and missed more often than targets with camouflage patterns. However, when stationary, targets with camouflage markings were captured less often and caused more false detections than those with striped patterns, which were readily detected.Conclusions
Our study provides the clearest evidence to date that some patterns inhibit the capture of moving targets, but that camouflage and motion dazzle are not complementary strategies. Therefore, the specific coloration that evolves in animals will depend on how the life history and ontogeny of each species influence the trade-off between the costs and benefits of motion dazzle and camouflage. 相似文献63.
Ramajayam Govindan Venkatachalam Sivabalan Shazia Fathima JH Umaphathy Vidhya Rekha Senthilkumar Kalimuthu Selvaraj Jayaraman Kirubhanand Chandrasekaran 《Bioinformation》2020,16(11):937
The MUC1 oncoprotein is known to be linked with different types of cancer. Therefore, it is of interest to document the molecular docking analysis of compounds from Justica adhatoda L with the MUC1 oncoprotein. We report the structure based molecular binding features compounds such as amrinone, ethambutol, pyrazinamide and vasicoline the MUC1 oncoprotein for further consideration in drug discovery. 相似文献
64.
Sandra Irwin Scott M. Pedley Linda Coote Anke C. Dietzsch Mark W. Wilson Anne Oxbrough Oisín Sweeney Karen M. Moore Rebecca Martin Daniel L. Kelly Fraser J. G. Mitchell Thomas C. Kelly John O’Halloran 《Biodiversity and Conservation》2014,23(3):697-714
As the area of plantation forest expands worldwide and natural, unmanaged forests decline there is much interest in the potential for planted forests to provide habitat for biodiversity. In regions where little semi-natural woodland remains, the biodiversity supported by forest plantations, typically non-native conifers, may be particularly important. Few studies provide detailed comparisons between the species diversity of native woodlands which are being depleted and non-native plantation forests, which are now expanding, based on data collected from multiple taxa in the same study sites. Here we compare the species diversity and community composition of plants, invertebrates and birds in Sitka spruce- (Picea sitchensis-) dominated and Norway spruce- (Picea abies-) dominated plantations, which have expanded significantly in recent decades in the study area in Ireland, with that of oak- and ash-dominated semi-natural woodlands in the same area. The results show that species richness in spruce plantations can be as high as semi-natural woodlands, but that the two forest types support different assemblages of species. In areas where non-native conifer plantations are the principle forest type, their role in the provision of habitat for biodiversity conservation should not be overlooked. Appropriate management should target the introduction of semi-natural woodland characteristics, and on the extension of existing semi-natural woodlands to maintain and enhance forest species diversity. Our data show that although some relatively easily surveyed groups, such as vascular plants and birds, were congruent with many of the other taxa when looking across all study sites, the similarities in response were not strong enough to warrant use of these taxa as surrogates of the others. In order to capture a wide range of biotic variation, assessments of forest biodiversity should either encompass several taxonomic groups, or rely on the use of indicators of diversity that are not species based. 相似文献
65.
Erik JM Toonen Pilar Barrera Jaap Fransen Arjan PM de Brouwer Agnes M Eijsbouts Pierre Miossec Hubert Marotte Hans Scheffer Piet LCM van Riel Barbara Franke Marieke JH Coenen 《Arthritis research & therapy》2012,14(6):R264
Introduction
The goal of this study is to investigate whether the -308G > A promoter polymorphism in the tumor necrosis factor alpha (TNFA) gene is associated with disease severity and radiologic joint damage in a large cohort of patients with rheumatoid arthritis (RA).Methods
A long-term observational early RA inception cohort (n = 208) with detailed information about disease activity and radiologic damage after 3, 6 and 9 years of disease was genotyped for the TNFA -308G > A promoter polymorphism (rs1800629). A longitudinal regression analysis was performed to assess the effect of genotype on RA disease severity and joint damage. Subsequently, a meta-analysis, including all publically available data, was performed to further test the association between joint erosions and the TNFA polymorphism. To learn more about the mechanism behind the effect of the polymorphism, RNA isolated from peripheral blood from RA patients (n = 66) was used for TNFA gene expression analysis by quantitative PCR.Results
Longitudinal regression analysis with correction for gender and disease activity showed a significant difference in total joint damage between GG and GA+AA genotype groups (P = 0.002), which was stable over time. The meta-analysis, which included 2,053 patients, confirmed an association of the genetic variant with the development of erosions (odds ratio 0.78, 95% CI 0.62, 0.98). No significant differences in TNFA gene expression were observed for the different genotypes, confirming earlier findings in healthy individuals.Conclusions
Our data confirm that the TNFA -308G > A promoter polymorphism is associated with joint damage in patients with RA. This is not mediated by differences in TNFA gene expression between genotypes. 相似文献66.
Frank JH Gijsen Francesco Migliavacca Silvia Schievano Laura Socci Lorenza Petrini Attila Thury Jolanda J Wentzel Anton FW van der Steen Patrick WS Serruys Gabriele Dubini 《Biomedical engineering online》2008,7(1):23
Background
The process of restenosis after a stenting procedure is related to local biomechanical environment. Arterial wall stresses caused by the interaction of the stent with the vascular wall and possibly stress induced stent strut fracture are two important parameters. The knowledge of these parameters after stent deployment in a patient derived 3D reconstruction of a diseased coronary artery might give insights in the understanding of the process of restenosis. 相似文献67.
68.
Optimal conditions for the analysis of Pasteurella haemolytica lipopolysaccharide by sodium dodecyl sulphate-polyacrylamide gel electrophoresis 总被引:2,自引:0,他引:2
R.L. Davies Q. Ali R. Parton J.G. Coote Alison Gibbs J.H. Freer 《FEMS microbiology letters》1991,90(1):23-28
Monomeric human calcitonin (hCT) gene and oligomeric hCT genes composed of two, three or four head-to-tail linked monomers were fused in-frame to the yeast alpha-factor leader coding sequence wild-type and fragile mutant Saccharomyces cerevisiae strains were transformed with the constructed plasmids and the yield of recombinant protein secreted into the culture medium was measured. The yeast cells secreted equal (molar) amounts of all of the hCT variants. The recombinant proteins remained stable in the growth medium for at least 3 days. The fragile cells secreted about 30% more hCT as compared to the wild-type yeast cells. 相似文献
69.
Induction of increased thermotolerance in Saccharomyces cerevisiae may be triggered by a mechanism involving intracellular pH. 总被引:5,自引:0,他引:5
Incubation of Saccharomyces cerevisiae at sub-lethal temperatures results in an increase in thermotolerance. This process is dependent not only on the sub-lethal temperature but also on the duration of sub-lethal heating. This indicates that the mechanism inducing thermotolerance is a time/temperature dose response. Other factors that induce thermotolerance include exposure to ethanol, sorbic acid and low external pH values. These factors induce thermotolerance after incubation in the presence of protein synthesis inhibitors, and they are all known to affect the intracellular pH (pHi). The acquisition of increased thermotolerance is minimal with sub-lethal heating under neutral external pH conditions. However, when the external pH is reduced to 4.0 the level of induced thermotolerance increases to a maximum value. Using a specific ATPase inhibitor, diethylstilboestrol (DES), ATPase activity was shown to be essential for the cell to survive heat stress. In addition, measurement of acid efflux, or ATPase activity, revealed that proton pumping from the cell increased by approximately 50% at sublethal temperatures that induce thermotolerance. This work has clearly implicated pHi perturbation as the triggering mechanism conferring thermotolerance on S. cerevisiae. 相似文献
70.
The morphology and chemistry of the scales of the orange roughy and the smooth and spiky oreo dories
Proton and deuteron microprobes were used to establish the two-, and three-dimensional patterns of calcium, fluorine, carbon and oxygen variation in the scales of the orange roughy (Hoplostethus atlanticus) smooth oreo dory (Pseudocyttus maculatus) and spiky oreo dory (Neocyttus rhomboidalis). 相似文献