Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2009
Authors
R Wu W. L. Guo X. R. Wang X. L. Wang T. T. Zhuang jihong liu clarke B. LiuAbstract
Genetic instability could be provoked as an unintended consequence of genetic engineering in plants. Here we report that the rice endogenous long terminal repeat (LTR) retrotransposon Tos17 was transpositionally activated only in transgenic calli and their regenerated plants produced by biolistic transformation in rice (Oryza sativa L.) ssp. japonica cv. Matsumae. Moreover, the transpositional activity of Tos17 was sustained after plant regeneration in the T0 generation, and produced new germinal insertions. In contrast, the element remained totally quiescent in calli and regenerated plants from tissue culture of this genotype. Nonetheless, transcriptional induction and cytosine demethylation of Tos17 were found to have occurred with no significant difference in both kinds of calli, tissue culture alone and transgenic. This suggests that callus culture is likely to have played an important role in destabilizing Tos17 in the direction towards transpositional activation, but that biolistic transformation is the direct causal factor.
Authors
R. Wu W. L. Guo X. R. Wang X. L. Wang T. T. Zhuang jihong liu clarke B. LiuAbstract
Genetic instability could be provoked as an unintended consequence of genetic engineering in plants. Here we report that the rice endogenous long terminal repeat (LTR) retrotransposon Tos17 was transpositionally activated only in transgenic calli and their regenerated plants produced by biolistic transformation in rice (Oryza sativa L.) ssp. japonica cv. Matsumae. Moreover, the transpositional activity of Tos17 was sustained after plant regeneration in the T0 generation, and produced new germinal insertions. In contrast, the element remained totally quiescent in calli and regenerated plants from tissue culture of this genotype. Nonetheless, transcriptional induction and cytosine demethylation of Tos17 were found to have occurred with no significant difference in both kinds of calli, tissue culture alone and transgenic. This suggests that callus culture is likely to have played an important role in destabilizing Tos17 in the direction towards transpositional activation, but that biolistic transformation is the direct causal factor.
Authors
Erik JonerAbstract
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Authors
Erik JonerAbstract
Nanotechnology has many potential future applications that may have a positive impact on the environment, such as more efficient photovoltaic energy generation, safe and efficient H2 storage, reduced energy requirements in electronics, illumination and transport, drinking water purification and remediation of various pollutants. On the other hand, several nanomaterials are suspected to pose risks both to human health and the environment if not properly handled. Hazards like toxicity and ecotoxicity have been demonstrated for a range of engineered nanoparticles, but risks are yet difficult to estimate in a reliable way due to lack of good exposure estimates. This aspect is a major determinant of risk, but difficult to quantify due to the nature of nanoparticles (size, changes in speciation and a range of detection related issues). It is truly a huge task to investigate the environmental impact of nanomaterials. Not only is there an ever increasing number of new nanomaterials being developed and a huge challenge to trace and detect these in organisms, tissues and cells. But in an environmental context there is also additional complications related to estimating exposure, accounting for interactions with environmental matrices like soil and water constituents which will inevitably affect bioavailability, and possible different modes of toxicity affecting organisms as different as bacteria and mammals. In addition to problems related to toxicity, environmental impact also comprises effects on non-living components of the environment, like atmospheric processes, stability of organic matter e.g. in soils etc. which may be affected by the release of nanoparticles in a manner that may affect the environment in more severe ways than local toxicity experienced by individual species.When estimates of environmental hazards and risks are available, it is also an important task to weight risks against costs and benefits. Clearly, a certain level of risk is acceptable if new nanoproducts replace old and more environmentally harmful ones, as may be the case in hull treatment of boats etc. On the other hand side, it is also necessary to take energy consumption during the entire life cycle and other resource costs into account. A recent criticism on the environmental side has thus been that energy requirements in nanomaterial production is disproportionately high and production yields are sometimes very low, as seen e.g. for carbon nanotubes. Not only does this mean high energy consumption and large amounts of potentially hazardous waste, but it also underpins the notion of nanotechnology as a sustainable technology. Yet another criticism regarding sustainability concerns resource economy, which relates particularly to metals like silver and rare earth elements that face depletion within our lifetime if consumption continues at current rates. Widespread use of e.g. antimicrobial silver coatings is strongly contributing to such a depletion, and many claim that its use is both futile and lays a basis for new problems with microbial resistance that will have a negative impact on public health, in addition to having a strong ecotoxicological potential.
Authors
Tor Håkon Sivertsen Josef Eitzinger Sabina Thaler Simone Orlandini Pavol Nejedlik Valentin Kazandjiev Dragutin MihailovicAbstract
During the past decades, many new software tools were developed to be used for agricultural research as well as for decision making. For example, crop and whole farm system modelling, pest and disease warning models/algorithms, models for irrigation scheduling or agroclimatic indices can help farmers significantly in decision-making for crop management options and related farm technologies. The aim of Working group 1 of COST734 was a review and assessment of agroclimatic indices and simulation models relevant for various European agricultural activities. The key results, based on a survey by questionnaires among the COST734 participating countries (see: http://www.cost734.eu/) and a literature survey, are presented in this study. It includes an overview of most used agrometeorological or agroclimatic indices and process oriented crop models for operational as well as scientific applications, an analysis of the limitations for applications and an overview of spatial applications in combination with GIS and remote sensing in Europe. The COST734 survey showed for example, that research activities regarding the development of agroclimatic indices in Europe are focused on indizes on drought, phenology, frost and heat stress. Process oriented crop models are mainly applied for wheat and maize, which is related to their importance in European crop production. In many cases there are still limitations of crop model applications in Europe, which often are related to the availability of input data. Spatial crop model applications including a combination with remote sensing data are still rare. There are a number of different models and indices in use, varying by regions and countries. From the survey it can be concluded that there is a need of standardisation and harmonization of applications of agroclimatic indices as well as crop models in Europe in order to allow inter-comparison of the results and to improve the interpretation of results.
Authors
Astrid JohansenAbstract
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Authors
Astrid JohansenAbstract
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Authors
Oddbjørn Kval-Engstad Astrid Sandvik Finn Avdem Øystein Havrevoll Astrid JohansenAbstract
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Abstract
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Authors
Astrid JohansenAbstract
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