48 research outputs found
From science to practice: Bringing innovations to agronomy and forestry
The challenge of the work presented here is to make innovative research output in the agronomy and forestry domain accessible to end-users, so that it can be practically applied. We have developed an approach that consists of three key-elements: an ontology with domain knowledge, a set of documents that have been annotated and meta-annotated, and a system (ask-Valerie) that is based on a dialogue to represent the interaction between end user and system.<br/> We show that the dialogue-metaphor is a good way of modelling the interaction between user and system. The system helps the user in formulating his question and in answering it in a useful way. Meta-annotations of key-paragraphs in the document-base turn out to be relevant in assessing in one glance what the content of a document is. <br/> End-users are very enthusiastic about the possibilities that ask-Valerie offers them in translating scientific results to their own situation
Analysis tools for single-monomer measurements of self-assembly processes
Protein assembly plays an important role throughout all phyla of life, both
physiologically and pathologically. In particular, aggregation and
polymerization of proteins are key-strategies that regulate cellular function.
In recent years, methods to experimentally study the assembly process on a
single-molecule level have been developed. This progress concomitantly has
triggered the question of how to analyze this type of single-filament data
adequately and what experimental conditions are necessary to allow a meaningful
interpretation of the analysis. Here, we developed two analysis methods for
single-filament data: the visitation analysis and the average-rate analysis. We
benchmarked and compared both approaches with the classic dwell-time-analysis
frequently used to study microscopic association and dissociation rates. In
particular, we tested the limitations of each analysis method along the lines
of the signal-to-noise ratio, the sampling rate, and the labeling efficiency
and bleaching rate of the fluorescent dyes used in single-molecule fluorescence
experiments. Finally, we applied our newly developed methods to study the
monomer assembly of actin at the single-molecule-level in the presence of the
class II nucleator Cappuccino and the WH2 repeats of Spire. For Cappuccino, our
data indicated fast elongation circumventing a nucleation phase whereas, for
spire, we found that the four WH2 motifs are not sufficient to promote de novo
nucleation of actin
De Novo Superinfection of Hepatitis B Virus in an Anti-HBs Positive Patient with Recurrent Hepatitis C Following Liver Transplantation
A 60-year-old woman with end stage liver cirrhosis caused by genotype 2 hepatitis C virus (HCV) infection received an orthotopic liver transplantation (OLT). The patient was negative for the hepatitis B surface antigen (HBsAg) and positive for the anti-hepatitis B surface antibody (anti-HBs) prior to and one and a half months following the OLT. Due to reactivation of hepatitis C, treatment with interferon-alpha and Ribavirin started two months following the OLT and resulted in a sustained virological response. We performed a liver biopsy because a biochemical response was not achieved. Surprisingly, liver pathology showed HBsAg-positive hepatocytes with a lobular hepatitis feature, which had been negative in the liver biopsy specimen obtained one and a half months post-OLT. High titers of both HBsAg and HBeAg were detected, while anti-HBs antibodies were not found. Tests for IgM anti-hepatitis B core antibody and anti-delta virus antibodies were negative. The serum HBV DNA titer was over 1×107 copies/mL. A sequencing analysis showed no mutation in the "a" determinant region, but revealed a mixture of wild and mutant strains at an overlapping region of the S and P genes (S codon 213 (Leu/Ile); P codons 221 (Phe/Tyr) and 222 (Ala/Thr)). These findings suggest that de novo hepatitis B can develop in patients with HCV infection during the post-OLT period despite the presence of protective anti-HBs
Comparative assessment of ecosystem C exchange in Miscanthusand reed canary grass during early establishment
peer-reviewedLand‐use change to bioenergy crop production can contribute towards addressing the dual challenges of greenhouse gas mitigation and energy security. Realisation of the mitigation potential of bioenergy crops is, however, dependent on suitable crop selection and full assessment of the carbon (C) emissions associated with land conversion. Using eddy covariance‐based estimates, ecosystem C exchange was studied during the early‐establishment phase of two perennial crops, C3 reed canary grass (RCG) and C4 Miscanthus, planted on former grassland in Ireland. Crop development was the main determinant of net carbon exchange in the Miscanthus crop, restricting significant net C uptake during the first 2 years of establishment. The Miscanthus ecosystem switched from being a net C source in the conversion year to a strong net C sink (−411 ± 63 g C m−2) in the third year, driven by significant above‐ground growth and leaf expansion. For RCG, early establishment and rapid canopy development facilitated a net C sink in the first 2 years of growth (−319 ± 57 (post‐planting) and −397 ± 114 g C m−2, respectively). Peak seasonal C uptake occurred three months earlier in RCG (May) than Miscanthus (August), however Miscanthus sustained net C uptake longer into the autumn and was close to C‐neutral in winter. Leaf longevity is therefore a key advantage of C4 Miscanthus in temperate climates. Further increases in productivity are projected as Miscanthus reaches maturity and are likely to further enhance the C sink potential of Miscanthus relative to RCG.Department of Agriculture, Food and the Marine, Irelan
Date Editor Explanation Status
Unconstrained pen interactions in crisis management scenarios Document histor