Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2017
Authors
Signe Kynding Borgen Gry Alfredsen Johannes Breidenbach Lise Dalsgaard Gunnhild Søgaard Aaron SmithAbstract
No abstract has been registered
Authors
Svetlana Saarela Johannes Breidenbach Pasi Raumonen Anton Grafström Göran Ståhl Mark J. Ducey Rasmus AstrupAbstract
This study presents an approach for predicting stand-level forest attributes utilizing mobile laser scanning data collected as a nonprobability sample. Firstly, recordings of stem density were made at point locations every 10th metre along a subjectively chosen mobile laser scanning track in a forest stand. Secondly, kriging was applied to predict stem density values for the centre point of all grid cells ina5m×5m lattice across the stand. Thirdly, due to nondetectability issues, a correction term was computed based on distance sampling theory. Lastly, the mean stem density at stand level was predicted as the mean of the point-level predictions multiplied with the correction factor, and the corresponding variance was estimated. Many factors contribute to the uncertainty of the stand-level prediction; in the variance estimator, we accounted for the uncertainties due to kriging prediction and due to estimating a detectability model from the laser scanning data. The results from our new approach were found to correspond fairly well to estimates obtained using field measurements from an independent set of 54 circular sample plots. The predicted number of stems in the stand based on the proposed methodology was 1366 with a 12.9% relative standard error. The corresponding estimate based on the field plots was 1677 with a 7.5% relative standard error.
Authors
Laur Manea Roger Manea Ole Martin EkloAbstract
Enzymes are major components of organism defense against toxic chemicals in their environment. Despite the passage of more than 200 million years of life presence these enzymes now play an important role in detoxifying chemicals man-made addiction and it may be a useful biomarker. Lactate dehydrogenase (LDH or LD) is intracellular enzyme year found early in all living cells (animals, plants, and prokaryotes). LDH catalyzes the conversion of pyruvic acid to lactic acid and back, as it converts NAD + to NADH and back. A dehydrogenase enzyme transfers a hydride from one molecule to another. LDH enzyme exists in four distinct classes: first is NAD (P) -dependent L-lactate dehydrogenase; other LDHs act on D-lactic and / or is dependent on cytochome C: Dlactate dehydrogenase (cytochome) and L-lactate (L-lactate dehydrogenase (cytochome). LDH is expressed extensively in body tissues, such as blood cells and heart muscle. Lactate dehydrogenase (LDH) is widely distributed throughout the body, as seen mainly in the kidney, myocardium, skeletal muscle, brain, liver and lungs. Because it is released during tissue damage, it is a marker of common injuries such as heart failure and disease.
Authors
Signe Kynding Borgen Gry Alfredsen Johannes Breidenbach Lise Dalsgaard Gunnhild Søgaard Aaron SmithAbstract
No abstract has been registered
Authors
Wenche DramstadAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Peeter Anijalg Simon Y. W. Ho John Davison Marju Keis Egle Tammeleht Katalina Bobowik Igor L. Tumanov Alexander P. Saveljev Elena A. Lyapunova Alexandr A. Vorobiev Nikolai I. Markov Alexey P. Kryukov Ilpo Kojola Jon Swenson Snorre Hagen Hans Geir Eiken Ladislav Paule Urmas SaarmaAbstract
Aim Climatic changes during the Late Pleistocene had major impacts on populations of plant and animal species. Brown bears and other large mammals are likely to have experienced analogous ecological pressures and phylogeographical processes. Here, we address several unresolved issues regarding the Late Pleistocene demography of brown bears: (1) the putative locations of refugia; (2) the direction of migrations across Eurasia and into North America; and (3) parallels with the demographic histories of other wild mammals and modern humans. Location Eurasia and North America. Methods We sequenced 110 complete mitochondrial genomes from Eurasian brown bears and combined these with published sequences from 138 brown bears and 33 polar bears. We used a Bayesian approach to obtain a joint estimate of the phylogeny and evolutionary divergence times. The inferred mutation rate was compared with estimates obtained using two additional methods. Results Bayesian phylogenetic analysis identified seven clades of brown bears, with most individuals belonging to a very large Holarctic clade. Bears from the widespread clade 3a1, which has a distribution from Europe across Asia to Alaska, shared a common ancestor about 45,000 years ago. Main conclusions We suggest that the Altai-Sayan region and Beringia were important Late Pleistocene refuge areas for brown bears and propose large-scale migration scenarios for bears in Eurasia and to North America. We also argue that brown bears and modern humans experienced a demographic standstill in Beringia before colonizing North America.
Authors
Jihong Liu Clarke Lisa Paruch Mihaela-Olivia Dobrica Iuliana Caras Catalin Tucureanu Adrian Onu Sonya Ciulean Crina Stavaru Andre van Eerde Hege Særvold Steen Sissel Haugslien Catalina Petrareanu Catalin Lazar Ioan Popescu Ralph Bock Jean Dubuisson Norica Branza-NichitaAbstract
No abstract has been registered
Authors
Jihong Liu Clarke Lisa Paruch Mihaela-Olivia Dobrica Iuliana Caras Catalin Tucureanu Adrian Onu Sonya Ciulean Crina Stavaru Andre van Eerde Yanliang Wang Hege Særvold Steen Sissel Haugslien Catalina Petrareanu Catalin Lazar Costin-loan Popescu Ralph Bock Jean Dubuisson Norica Branza-NichitaAbstract
The hepatitis C virus (HCV) is a major etiologic agent for severe liver diseases ( e.g . cirrhosis, fibrosis and hepatocellular carcinoma). Approximately 140 million people have chronic HCV infections and about 500 000 die yearly from HCV-related liver pathologies. To date, there is no licensed vaccine available to prevent HCV infection and production of a HCV vaccine remains a major challenge. Here, we report the successful production of the HCV E1E2 heterodimer, an important vaccine candidate, in an edible crop (lettuce, Lactuca s ativa ) using Agrobacterium - mediated transient expression technology. The wild-type dimer (E1E2) and a variant without an N-glycosylation site in the E2 polypeptide (E1E2 Δ N6) were expressed, and appropriate N-glycosylation pattern and functionality of the E1E2 dimers were demonstrated. The humoral immune response induced by the HCV proteins was investigated in mice following oral administration of lettuce antigens with or without previous intramuscular prime with the mammalian HEK293T cell-expressed HCV dimer. Immunization by oral feeding only resulted in development of weak serum levels of anti-HCV IgM for both antigens; however, the E1E2 Δ N6 proteins produced higher amounts of secretory IgA, suggesting improved immunogenic properties of the N-glycosylation mutant. The mice group receiving the intramuscular injection followed by two oral boosts with the lettuce E1E2 dimer developed a systemic but also a mucosal immune response, as demonstrated by the presence of anti-HCV secretory IgA in faeces extracts. In summary, our study demonstrates the feasibility of producing complex viral antigens in lettuce, using plant transient expression technology, with great potential for future low-cost oral vaccine development.
Authors
Inger Martinussen Anne Linn Hykkerud Ivan Paponov Mette Thomsen Eivind Uleberg Laura JaakolaAbstract
No abstract has been registered