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101.
Virulence markers associated with Trueperella pyogenes infections in livestock and companion animals 下载免费PDF全文
102.
Summer-active (continental) and summer-dormant (Mediterranean) tall fescue morphotypes are each adapted to different environmental conditions. Endophyte presence provides plant parasitic nematode resistance, but not with all endophyte strains and cultivar combinations. This study sought to compare effects of four nematode genera on continental and Mediterranean cultivars infected with common toxic or novel endophyte strains. A 6-mon greenhouse study was conducted with continental cultivars, Kentucky 31 (common toxic) and Texoma MaxQ II (novel endophyte) and the Mediterranean cultivar Flecha MaxQ (novel endophyte). Endophyte-free plants of each cultivar were controls. Each cultivar × endophyte combination was randomly assigned to a control, low or high inoculation rate of a mixed nematode culture containing stunt nematodes (Tylenchorhynchus spp.), ring nematodes (Criconemella spp.), spiral nematodes (Helicotylenchus spp.), and lesion nematodes (Pratylenchus spp.). Endophyte infection had no effect on nematode population densities. The cultivar × endophyte interaction was significant. Population densities of stunt nematode, spiral nematode, and ring nematodes were higher for Flecha MaxQ than other cultivar × endophyte combinations. Novel endophyte infection enhances suitability of Flecha MaxQ as a nematode host. 相似文献
103.
Sugarcane (Saccharum X officinarum): A Reference Study for the Regulation of Genetically Modified Cultivars in Brazil 总被引:1,自引:0,他引:1
Cheavegatti-Gianotto A de Abreu HM Arruda P Bespalhok Filho JC Burnquist WL Creste S di Ciero L Ferro JA de Oliveira Figueira AV de Sousa Filgueiras T Grossi-de-Sá MD Guzzo EC Hoffmann HP de Andrade Landell MG Macedo N Matsuoka S de Castro Reinach F Romano E da Silva WJ de Castro Silva Filho M César Ulian E 《Tropical plant biology》2011,4(1):62-89
Global interest in sugarcane has increased significantly in recent years due to its economic impact on sustainable energy production. Sugarcane breeding and better agronomic practices have contributed to a huge increase in sugarcane yield in the last 30?years. Additional increases in sugarcane yield are expected to result from the use of biotechnology tools in the near future. Genetically modified (GM) sugarcane that incorporates genes to increase resistance to biotic and abiotic stresses could play a major role in achieving this goal. However, to bring GM sugarcane to the market, it is necessary to follow a regulatory process that will evaluate the environmental and health impacts of this crop. The regulatory review process is usually accomplished through a comparison of the biology and composition of the GM cultivar and a non-GM counterpart. This review intends to provide information on non-GM sugarcane biology, genetics, breeding, agronomic management, processing, products and byproducts, as well as the current technologies used to develop GM sugarcane, with the aim of assisting regulators in the decision-making process regarding the commercial release of GM sugarcane cultivars. 相似文献
104.
We analysed the relative effects of food availability and temperature on rates of growth and development of a predatory planktonic
water mite, Piona exigua. Growth in length of mites fed Daphnia, Ceriodaphnia and Chydorus was analysed by Gompertz or von Bertalanffy curves; these curves were compared by parallel curve analysis.
Growth rates of nymphs and adult female mites increased with temperature; the duration of the imagochrysalis stage decreased.
Females grown at 10 °C were smaller at final size than females grown at 15 °C, 18 °C or 22 °C. Females reared at food levels
of 15 or 30 prey l−1 grew more slowly and were smaller than those provided with 60 or 120 prey l−1.
Nymphs grew more slowly when Daphnia were the only prey, than when smaller prey were available. Food level did not affect nymph growth at 10 °C or 15 °C, but
growth at 18 °C or 22 °C may have been slowed at the lowest food levels. Synergistic effects of temperature and food level
on nymph growth were apparent only from analysis of growth curves and not from stage duration data. 相似文献
105.
Colin Green David A. Richards Jacqueline J. Hill Linda Gask Karina Lovell Carolyn Chew-Graham Peter Bower John Cape Stephen Pilling Ricardo Araya David Kessler J. Martin Bland Simon Gilbody Glyn Lewis Chris Manning Adwoa Hughes-Morley Michael Barkham 《PloS one》2014,9(8)
Background
Collaborative care is an effective treatment for the management of depression but evidence on its cost-effectiveness in the UK is lacking.Aims
To assess the cost-effectiveness of collaborative care in a UK primary care setting.Methods
An economic evaluation alongside a multi-centre cluster randomised controlled trial comparing collaborative care with usual primary care for adults with depression (n = 581). Costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICER) were calculated over a 12-month follow-up, from the perspective of the UK National Health Service and Personal Social Services (i.e. Third Party Payer). Sensitivity analyses are reported, and uncertainty is presented using the cost-effectiveness acceptability curve (CEAC) and the cost-effectiveness plane.Results
The collaborative care intervention had a mean cost of £272.50 per participant. Health and social care service use, excluding collaborative care, indicated a similar profile of resource use between collaborative care and usual care participants. Collaborative care offered a mean incremental gain of 0.02 (95% CI: –0.02, 0.06) quality-adjusted life-years over 12 months, at a mean incremental cost of £270.72 (95% CI: –202.98, 886.04), and resulted in an estimated mean cost per QALY of £14,248. Where costs associated with informal care are considered in sensitivity analyses collaborative care is expected to be less costly and more effective, thereby dominating treatment as usual.Conclusion
Collaborative care offers health gains at a relatively low cost, and is cost-effective compared with usual care against a decision-maker willingness to pay threshold of £20,000 per QALY gained. Results here support the commissioning of collaborative care in a UK primary care setting. 相似文献106.
107.
We have produced several new macroscopic crystal forms and a variety of microcrystals from modified flbrinogens. Bovine and rabbit flbrinogens crystallize after limited digestion by a bacterial protease or α-chymotrypsin. The fibrinogens making up these crystals are largely intact and highly clottable. Tentative molecular packing arrangements for two crystal forms have been deduced. The crystal morphology and cleavage planes were used in this analysis. The characteristic α-helical coiled-coil reflections arid spikes of intensity in certain directions in the crystal X-ray patterns serve as markers for the orientation of the fibrinogen molecules. Changes that occur in one of the forms during preparation for electron microscopy, as shown by comparison with X-ray experiments on crystals in various stains and solvents, support this packing model. These studies provide preliminary evidence that fibrinogen is about 450 Å in length and that the molecules bond end-to-end to form filaments making up the crystals. 相似文献
108.
Júlia R. de Rezende Thomas B. P. Oldenburg Tetyana Korin William D. L. Richardson Milovan Fustic Carolyn M. Aitken Bernard F. J. Bowler Angela Sherry Alexander Grigoryan Gerrit Voordouw Stephen R. Larter Ian M. Head Casey R. J. Hubert 《Environmental microbiology》2020,22(8):3049-3065
Most of the oil in low temperature, non-uplifted reservoirs is biodegraded due to millions of years of microbial activity, including via methanogenesis from crude oil. To evaluate stimulating additional methanogenesis in already heavily biodegraded oil reservoirs, oil sands samples were amended with nutrients and electron acceptors, but oil sands bitumen was the only organic substrate. Methane production was monitored for over 3000 days. Methanogenesis was observed in duplicate microcosms that were unamended, amended with sulfate or that were initially oxic, however methanogenesis was not observed in nitrate-amended controls. The highest rate of methane production was 0.15 μmol CH4 g−1 oil d−1, orders of magnitude lower than other reports of methanogenesis from lighter crude oils. Methanogenic Archaea and several potential syntrophic bacterial partners were detected following the incubations. GC–MS and FTICR–MS revealed no significant bitumen alteration for any specific compound or compound class, suggesting that the very slow methanogenesis observed was coupled to bitumen biodegradation in an unspecific manner. After 3000 days, methanogenic communities were amended with benzoate resulting in methanogenesis rates that were 110-fold greater. This suggests that oil-to-methane conversion is limited by the recalcitrant nature of oil sands bitumen, not the microbial communities resident in heavy oil reservoirs. 相似文献
109.
Ivy-Israel Natascha M. D. Moore Carolyn E. Schwartz Tonia S. Steury Todd D. Zohdy Sarah Newbolt Chad H. Ditchkoff Stephen S. 《Evolutionary ecology》2021,35(3):513-535
Evolutionary Ecology - Body size and secondary sexual characteristics are drivers of male reproductive success among polygynous species. A gene complex found to be associated with morphology in... 相似文献
110.
Yang Yang Hart Stephen C. McCorkle Emma P. Stacy Erin M. Barnes Morgan E. Hunsaker Carolyn T. Johnson Dale W. Berhe Asmeret Asefaw 《Ecosystems》2021,24(8):1853-1874
Ecosystems - Understanding the transport of dissolved organic carbon (DOC) and nitrogen (N) as water flows through headwater basins is important for predicting downstream water quality. With... 相似文献