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151.
Lars G. F. Tellnes Lone Ross Gobakken Per Otto Flæte Gry Alfredsen 《Wood material science & engineering》2014,9(3):139-143
AbstractThe outer facade constitutes a substantial volume of the total consumption of materials used in a building and the need for maintenance of the facade makes it especially interesting from a life cycle perspective. The range of wooden materials and products used for facades has different impacts over the life cycle, but the analyses so far have not included a time-adjusted global warming potential (GWP). Wooden facade materials were assessed with respect to their life cycle carbon footprint based on the environmental product declarations (EPD) and adjusted according to EN15804. The results showed low impacts of untreated Scots pine heartwood (≈1 kg CO2-eq. per square meter [m2]), medium for thermally modified Scots pine, coated Norway spruce and oil/copper–organic preservative-treated Scots pine (1–5 kg CO2-eq. per m2) and high for furfurylated Scots pine and acetylated Radiata pine (5–10 kg CO2-eq. per m2). The results with time-adjustment showed that these methods have a potential large effect on the carbon footprint of wooden claddings. The inclusion of biogenic carbon flows and timing seems to be more important than the difference between the product when biogenic carbon is not included. This fact highlights the importance time-adjusted GWP would have for wood products EPDs. 相似文献
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154.
The downward velocity of Pb and Cs in undisturbed European forest soils is determined from the depth distribution of atmospheric 210Pb , and from the penetration depth of the bomb Cs peak in the soil. The downward velocity of Pb and Cs shows no correlation with soil type and pH. The downward migration of Pb and Cs is found to be due to an apparent downward movement of organic material, caused by the sedimentation of soil organic matter and subsequent turnover into CO2 . Cs migration, however, shows an additional velocity component which is found to depend on the turnover rate of soil organic matter. 相似文献
155.
Summary The production of transgenic plants by means of direct gene transfer to protoplasts is now a widely-used technique. The biological mechanisms underlying the transformation are still poorly understood, but many investigations have attempted to shed light on some components of this process. Varying the experimental conditions has in some cases led to better transformation rates, but further improvements of the protocols are possible. Such improvements will require a better understanding of how the alien DNA enters the cells, becomes integrated into the chromosomes and is treated as a part of the plant genome. Irradiation with sublethal doses of X-rays or UV-light has been shown to increase the transformation frequency, while certain drugs have been shown to act in a similar manner. The effects of these and other factors are discussed.Abbreviations Aph
aphidicolin
- ATF
absolute transformation frequency
- BLM
bleomycin
- CaMV
cauliflower mosaic virus
- CAT
chloramphenicol acetyl transferase
- CHO
Chinese hamster ovary cells
- EF
enhancement factor
- Nos
nopaline synthase
- NPTII
neomycin phosphotransferase II
- Ocs
octopine synthase
- PEG
polyethyleneglycol
- RTF
relative transformation frequency 相似文献
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157.
Towards breeding of triploid chamomile (Matricaria recutita L.) – Ploidy variation within German chamomile of various origins 下载免费PDF全文
Lars‐Gernot Otto Wolfram R. Junghanns Andreas Plescher Marlis Sonnenschein Timothy F. Sharbel 《Plant Breeding》2015,134(4):485-493
German chamomile is an important medical plant with a long history of usage and a wide range of medical applications. Wild forms are diploid, whereas cultivated ones are diploid and tetraploid. Ploidy level variation within 15 origins (varieties, accessions, populations) of chamomile was investigated. Both naturally occurring triploids and those induced through directed crosses between diploid and tetraploid parents were identified and analysed, and these data could facilitate the exploitation of triploidy in chamomile as in other crop plants (fruit and ornamental plants). 相似文献
158.
One of the major tasks of experimental farms is the determination of productivity with regard to the regionally differing natural, technological, and socio-economic boundary conditions. In order to achieve this aim the location of the respective stations must be regionally representative from the viewpoint of the major factors controlling agrarian production. In paradigmatic representation, i.e. focusing the very interest on soil qualities and dealing with the north-eastern part of Ghana as a developing country, this article describes a cogent method for defining local representativity of production sites by means of classification procedures and biplot calculus. The application of the latter derivative of matrix calculus appears absolutely necessary for defining those results of clustering procedures which are interpretable in factual terms. 相似文献
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160.
Archipow W Lanz OI 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(11):1215-1218
The clinical use and outcome of the rectus abdominis muscle flap to repair prepubic hernias were evaluated retrospectively. Medical records (2002-2007) of 8 dogs that had a rectus abdominis muscle flap to repair traumatic prepubic tendon rupture were reviewed. Only minor donor site complications were noted, including self-limiting ventral and hind-limb swelling. No long-term complications including recurrence of hernia were noted. The results of this study indicate that the rectus abdominis muscle flap is a clinically useful option for repairing prepubic tendon rupture in dogs. 相似文献