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401.
Jari Liski Sanna Kaasalainen Pasi Raumonen Anu Akujärvi Anssi Krooks Anna Repo Mikko Kaasalainen 《Global Change Biology Bioenergy》2014,6(6):777-784
Indirect carbon dioxide emissions from producing bioenergy from tree stumps and roots depend critically on the decomposition rate of these harvest residues if they were left in forest to decay. We developed a method to improve the current estimates of these emissions. First, the 3D structure of uprooted stump‐root systems was modeled based on terrestrial laser‐scanning data. Second, information obtained on the size distribution of the stumps and the roots was used to simulate their decomposition and to estimate the indirect emissions. The method was able to describe the structure of stump‐root systems at a clear‐cut boreal Norway spruce test site. Compared with earlier results based on the diameter of stumps alone, the new estimates of the decomposition rate were slightly higher and, consequently, those of the indirect emissions slightly lower. The method is useful to collect information on the indirect emissions of stump‐root bioenergy quickly in different forests. 相似文献
402.
Pasi Laihonen Mia Rönkä Harri Tolvanen Risto Kalliola 《Biodiversity and Conservation》2003,12(1):103-120
To function effectively, the international biodiversity Clearing HouseMechanism (CHM), based on the Convention on Biological Diversity (CBD), needs tobe rooted at the regional and local levels. This article presents an example ofhow stakeholders of regional data and information can be encouraged to formnetworks linked to national biodiversity focal points (NFPs). We pay specialattention to exploiting the geospatial properties of biodiversity data andinformation, and demonstrate how data and information can best be filtered,classified and labelled to facilitate geographically based information retrievalon the Internet. The geocodability of bibliographic reports proved to be poor,indicating an urgent need to reconsider the geographical properties ofbiodiversity information under production. Also, it is useful to utilisenetworking processes with information from fields other than biodiversity wheninitiating the network. Finally, we present and discuss problems of integrityand interoperability of data, and also the process of biodiversity informationproduction from the point of view of general information theory and innovationsoffered by modern information technology. 相似文献
403.
The gene for the alpha 1(IV) chain of human type IV procollagen: the exon structures do not coincide with the two structural subdomains in the globular carboxy-terminus of the protein. 总被引:2,自引:0,他引:2 下载免费PDF全文
Previous studies on the coding sequences of DNAs for the alpha 1(IV) chain of basement membrane collagen demonstrated a striking homology between the first 115 and the second 114 amino acids of the globular (NC1) domain of the protein. Also, alignment of the 12 cysteine residues indicated that the homology was particularly strong around three paired clusters of amino acids around cysteine residues. Here we have isolated a cosmid clone containing the 3'-end of the gene. Analysis of the clone and previously isolated lambda clones demonstrated that the intron--exon patterns of the gene does not reflect the homology in the protein. Therefore the homology cannot have arisen in any simple manner from gene duplications. 相似文献
404.
405.
Kathy Darragh Anna Orteu Daniella Black Kelsey J. R. P. Byers Daiane Szczerbowski Ian A. Warren Pasi Rastas Ana Pinharanda John W. Davey Sylvia Fernanda Garza Diana Abondano Almeida Richard M. Merrill W. Owen McMillan Stefan Schulz Chris D. Jiggins 《PLoS biology》2021,19(1)
Plants and insects often use the same compounds for chemical communication, but not much is known about the genetics of convergent evolution of chemical signals. The terpene (E)-β-ocimene is a common component of floral scent and is also used by the butterfly Heliconius melpomene as an anti-aphrodisiac pheromone. While the biosynthesis of terpenes has been described in plants and microorganisms, few terpene synthases (TPSs) have been identified in insects. Here, we study the recent divergence of 2 species, H. melpomene and Heliconius cydno, which differ in the presence of (E)-β-ocimene; combining linkage mapping, gene expression, and functional analyses, we identify 2 novel TPSs. Furthermore, we demonstrate that one, HmelOS, is able to synthesise (E)-β-ocimene in vitro. We find no evidence for TPS activity in HcydOS (HmelOS ortholog of H. cydno), suggesting that the loss of (E)-β-ocimene in this species is the result of coding, not regulatory, differences. The TPS enzymes we discovered are unrelated to previously described plant and insect TPSs, demonstrating that chemical convergence has independent evolutionary origins.Plants and insects often use the same compounds for chemical communication, but little is known about the convergent evolution of such chemical signals. This study identifies a novel terpene synthase involved in production of an anti-aphrodisiac pheromone by the butterfly Heliconius melpomene. This enzyme is unrelated to other insect terpene synthases, providing evidence that the ability to synthesise terpenes has arisen multiple times independently within the insects. 相似文献