排序方式: 共有22条查询结果,搜索用时 46 毫秒
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Gladys Ludevese‐Pascual Farhana Ahmed Marleen De Troch Edgar Amar Joseph Leopoldo Laranja Samuel Bode Pascal Boeckx Peter Bossier Peter De Schryver 《Journal of the World Aquaculture Society》2021,52(1):184-194
A preliminary study was conducted to demonstrate fate of the bacterial storage compound poly‐β‐hydroxybutyrate (PHB) once ingested and degraded in vivo in crustaceans. The 2% supplementation of 13C‐labeled Ralstonia eutropha DSM545 containing 75% PHB on dry weight in postlarval whiteleg shrimp, Litopenaeus vannamei resulted in consistent enrichment of two fatty acids (containing 14–24 carbons [C] in length ) pentadecanoic acid (15:0) and palmitic acid (16:0) in all lipid fractions. This could indicate that 13C signal may not only originate from the PHB but partly from the structural components of the bacterial cell. There was a trend of lower 13C enrichment in various lipid fractions of the postlarvae as compared to the diet. These findings may have important implications as to potential of PHB as energy source rather than as building block. There was a rapid transfer of 13C in the postlarvae as seen by the significant 13C enrichment in the tissues 4 hr after feeding with labeled bacterial cells. Overall, the assimilation of PHB in crustacean tissues is demonstrated for the first time. Our results indicate that PHB once ingested is rapidly assimilated in the tissues and could probably act as an energy source rather than as a building block. 相似文献
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Pinheiro VB Taylor AI Cozens C Abramov M Renders M Zhang S Chaput JC Wengel J Peak-Chew SY McLaughlin SH Herdewijn P Holliger P 《Science (New York, N.Y.)》2012,336(6079):341-344
Genetic information storage and processing rely on just two polymers, DNA and RNA, yet whether their role reflects evolutionary history or fundamental functional constraints is currently unknown. With the use of polymerase evolution and design, we show that genetic information can be stored in and recovered from six alternative genetic polymers based on simple nucleic acid architectures not found in nature [xeno-nucleic acids (XNAs)]. We also select XNA aptamers, which bind their targets with high affinity and specificity, demonstrating that beyond heredity, specific XNAs have the capacity for Darwinian evolution and folding into defined structures. Thus, heredity and evolution, two hallmarks of life, are not limited to DNA and RNA but are likely to be emergent properties of polymers capable of information storage. 相似文献
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Van Droogenbroeck C Van Risseghem M Braeckman L Vanrompay D 《Veterinary microbiology》2009,135(1-2):31-37
Chlamydophila (C.) psittaci, a category B bioterrorism agent, causes respiratory disease in birds and psittacosis or parrot fever in man. The disease spreads aerogenically and no vaccines are available for either birds or man. Highly sensitive C. psittaci bioaerosol monitoring methods are unavailable. We evaluated: (1) dry filtration for collecting C. psittaci from contaminated air using different samplers and membrane filters, (2) impingement into different liquid collection media by use of the AGI-30 impinger and the BioSampler and (3) impaction into newly designed C. psittaci media utilizing the MAS-100 aerosol impactor. For personal bioaerosol sampling, we recommend the use of a gelatin filter in combination with the IOM inhalable dust sampler at an airflow rate of 2L/min. This allowed the detection of 10 organisms of C. psittaci by both PCR and culture. For stationary bioaerosol monitoring, sampling 1000L of air in 10min with the MAS-100 impactor and ChlamyTrap 1 impaction medium was most efficient and made it possible to detect 1 and 10 C. psittaci organisms by PCR and culture, respectively. ChlamyTrap 1 in combination with the MAS-100 impactor might also be applicable for bioaerosol monitoring of viruses. 相似文献
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Jan?SerroyenEmail author Geert?Molenberghs Marleen?Verhoye Vincent?Van?Meir Annemie?Van der?Linden 《Journal of Agricultural, Biological & Environmental Statistics》2005,10(2):170-183
We analyze data on the impact of testosterone on the dynamics of Mn2+ accumulation measured by magnetic resonance imaging in three songbird brain areas: the nucleus robustus arcopallii (RA),
area X, and the high vocal center (HVC). Birds with and without testosterone were included in the experiment, and repeated
measurements were available in both a preand post-drug administration period. We formulate a nonlinear modeling strategy,
allowing for the incorporation of (1) within-bird correlation, (2) the nonlinearity of the profiles, and (3) the effect of
treatment. For two of the outcomes (RA and area X), biological theory suggests a parametric form, but for HVC this is not
the case. Because the HVC outcome bears some resemblance with the two-compartment model known from pharmacokinetics, this
model was considered a sensible choice. We use a different model, based on fractional polynomials, as a sensitivity analysis
for the latter. All methods used provide good fits to the data, confirm results from previous, simple analyses undertaken
in the literature, but were able to detect additional effects of treatment that had so far gone undetected. The fractional
polynomial and two-compartment models provide similar substantive conclusions; the two together can be seen as a form of sensitivity
analysis. 相似文献
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Marleen van de Kerkhof Annemarie Groot Marien Borgstein Leontien Bos-Gorter 《Agriculture and Human Values》2010,27(3):307-319
Environmental pollution, animal diseases, and food scandals have marked the agricultural sector in the Netherlands and elsewhere
in the 1990s. The sector was high on the political and societal agenda and plans were developed to redesign the sector into
a more sustainable direction. Generally, monitoring of the agricultural sector is done by means of quantitative indicators
to measure social, ecological, and economic performance. To give more attention to the normative character of sustainable
development, the Dutch Ministry of Agriculture, Nature, and Food Quality requested for a participatory approach to evaluate
Dutch agriculture, which was characterized by stakeholder workshops, dialogue, and learning. This article describes and reflects
on this approach, using the Fourth Generation Evaluation framework developed by Guba and Lincoln (Fourth generation evaluation,
1989). Although there are several improvements to be made, the evaluation approach was successful in the way that it gave insight
into perceptions, visions, and ambitions of agricultural stakeholders with regard to sustainability. It also encouraged learning
about ways to make the agricultural sector more sustainable. And it contributed to the development of a monitoring approach
that is complementary to the quantitative, indicator-based, evaluation approach that is generally used and that can be used
every few years to see how perceptions and ambitions of stakeholders have developed. 相似文献
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Daniel Goitom Asfaha Christophe R. Quétel Freddy Thomas Micha Horacek Bernhard Wimmer Gerhard Heiss Christian Dekant Peter Deters-Itzelsberger Stefan Hoelzl Susanne Rummel Christophe Brach-Papa Marleen Van Bocxstaele Eric Jamin Malcolm Baxter Katharina Heinrich Simon Kelly Daniela Bertoldi Luana Bontempo Federica Camin Roberto Larcher Matteo Perini Andreas Rossmann Antje Schellenberg Claus Schlicht Heinz Froeschl Jurian Hoogewerff Henriette Ueckermann 《Journal of Cereal Science》2011
The aim of this work (from the FP6 project TRACE) was to develop methods based on the use of geochemical markers for the authentication of the geographical origin of cereal samples in Europe (cf. EC regulations 2081/92 and 1898/06). For the first time, the potential usefulness of combining n(87Sr)/n(86Sr) and δ13C, δ15N, δ18O and δ34S isotopic signatures, alone or with key element concentrations ([Na], [K], [Ca], [Cu] and [Rb], progressively identified out of 31 sets of results), was investigated through multiple step multivariate statistics for more than 500 cereal samples collected over 2 years from 17 sampling sites across Europe representing an extensive range of geographical and environmental characteristics. 相似文献
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