2,928 research outputs found
Genetic parameters for lignin, extractives and decay in Eucalyptus globulus
Eucalyptus globulus is grown in temperate regions of the world for pulp production. The chemical composition of its wood including the proportion of cellulose, lignin and extractives, make it highly suited to this purpose. This study analysed genetic variation in these traits and decay, for nine localities of E. globulus. Heritability estimates were also obtained, and the relationships between these traits and the physical wood traits and growth were examined. Significant genetic variation was found between localities for lignin content (Klason lignin and acid-soluble lignin contents) and decay. The only trait for which significant variation between families within locality was detected was acid-soluble lignin content, which resulted in this trait also having the only significant narrow-sense heritability (0.51 0.26). Family means heritabilities were high for lignin content, extractives content and decay (0.42-0.64). The chemical wood traits were highly correlated with each other both phenotypically and genetically, with important correlations found with density and microfibril angle. Correlations suggested that during selection for the breeding objective traits, it is likely that favourable states in the chemical wood traits, decay resistance and fibre properties are concurrently being selected, whereas growth may be selected for independently. This initial study provides a stepping stone for future studies where particular localities of the breeding population may be characterised further
Data on Deck: A Case Study of a Historic Undersea Film and Video Digitization Project
In 2021, the Woods Hole Oceanographic Institution (WHOI) Data Library and Archives (DLA), a part of the MBLWHOI (Marine Biological Laboratory Woods Hole Oceanographic Institution) Library, received a grant from the Council on Library and Information Resources (CLIR) Recordings at Risk (RAR) program to catalog, digitize, preserve, and make available historic films and videos of Alvin, the first-of-its-kind manned submersible vessel that has shown us more of the deep ocean than had ever been possible and transformed our understanding of life on Earth.
These moving images have not been accessible to researchers and were far past the intended life cycle of their respective media formats. There was significant risk of complete image loss of these groundbreaking films if we attempted to view them. With the CLIR grant, we were able to migrate these significant moving images. In this paper, we will share our experience of designing and implementing this project, we will document the historic importance of these films, and we will briefly review the current literature on archival digitization and digital preservation practices
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Landslides on Ceres: Diversity and Geologic Context.
Landslides are among the most widespread geologic features on Ceres. Using data from Dawn's Framing Camera, landslides were previously classified based upon geomorphologic characteristics into one of three archetypal categories, Type 1(T1), Type 2 (T2), and Type 3 (T3). Due to their geologic context, variation in age, and physical characteristics, most landslides on Ceres are, however, intermediate in their morphology and physical properties between the archetypes of each landslide class. Here we describe the varied morphology of individual intermediate landslides, identify geologic controls that contribute to this variation, and provide first-order quantification of the physical properties of the continuum of Ceres's surface flows. These intermediate flows appear in varied settings and show a range of characteristics, including those found at contacts between craters, those having multiple trunks or lobes; showing characteristics of both T2 and T3 landslides; material slumping on crater rims; very small, ejecta-like flows; and those appearing inside of catenae. We suggest that while their morphologies can vary, the distribution and mechanical properties of intermediate landslides do not differ significantly from that of archetypal landslides, confirming a link between landslides and subsurface ice. We also find that most intermediate landslides are similar to Type 2 landslides and formed by shallow failure. Clusters of these features suggest ice enhancement near Juling, Kupalo and Urvara craters. Since the majority of Ceres's landslides fall in the intermediate landslide category, placing their attributes in context contributes to a better understanding of Ceres's shallow subsurface and the nature of ground ice
Applying the 3C Model to FLOSS communities
Publicado em "Collaboration and technology: 22nd International Conference, CRIWG 2016, Kanazawa, Japan, September 14-16, 2016, proceedings". ISBN 978-3-319-44798-8How learning occurs within Free/Libre Open Source (FLOSS)
communities and what is the dynamics such projects (e.g. the life cycle
of such projects) are very relevant questions when considering the use of
FLOSS projects in a formal education setting. This paper introduces an
approach based on the 3C collaboration model (communication, coordination
and cooperation) to represent the collaborative learning dynamics
within FLOSS communities. To explore the collaborative learning potential
of FLOSS communities a number of questionnaires and interviews
to selected FLOSS contributors were run. From this study a 3C collaborative
model applicable to FLOSS communities was designed and
discussed.Programa Operacional da Região Norte, NORTE2020, in the context of project NORTE-01-0145-FEDER-000037FCT under grant SFRH/BSAB/113890/201
Genetic parameters for growth, wood density and pulp yield in Eucalyptus globulus
Genetic variation and co-variation among the key
pulpwood selection traits for Eucalyptus globulus were
estimated for a range of sites in Portugal, with the aim of
improving genetic parameters used to predict breeding
values and correlated response to selection. The trials
comprised clonally replicated full-sib families (eight trials)
and unrelated clones (17 trials), and exhibited varying
levels of pedigree connectivity. The traits studied were stem
diameter at breast height, Pilodyn penetration (an indirect
measure of wood basic density) and near infrared reflectance
predicted pulp yield. Univariate and multivariate
linear mixed models were fitted within and across sites, and estimates of additive genetic, total genetic, environmental
and phenotypic variances and covariances were obtained.
All traits studied exhibited significant levels of additive
genetic variation. The average estimated within-site narrowsense
heritability was 0.19±0.03 for diameter and 0.29±
0.03 for Pilodyn penetration, and the pooled estimate for
predicted pulp yield was 0.42±0.14. When they could be
tested, dominance and epistatic effects were generally not
statistically significant, although broad-sense heritability
estimates were slightly higher than narrow-sense heritability
estimates. Averaged across trials, positive additive
(0.64±0.08), total genetic (0.58±0.04), environmental
(0.38±0.03) and phenotypic (0.43±0.02) correlation estimates
were consistently obtained between diameter and
Pilodyn penetration. This data argues for at least some form
of pleiotropic relationship between these two traits and that
selection for fast growth will adversely affect wood density
in this population. Estimates of the across-site genetic
correlations for diameter and Pilodyn penetration were
high, indicating that the genotype by environment interaction
is low across the range of sites tested. This result
supports the use of single aggregated selection criteria for
growth and wood density across planting environments in
Portugal, as opposed to having to select for performance in
different environment
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Functional Group and Substructure Searching as a Tool in Metabolomics
BACKGROUND: A direct link between the names and structures of compounds and the functional groups contained within them is important, not only because biochemists frequently rely on literature that uses a free-text format to describe functional groups, but also because metabolic models depend upon the connections between enzymes and substrates being known and appropriately stored in databases. METHODOLOGY: We have developed a database named "Biochemical Substructure Search Catalogue" (BiSSCat), which contains 489 functional groups, >200,000 compounds and >1,000,000 different computationally constructed substructures, to allow identification of chemical compounds of biological interest. CONCLUSIONS: This database and its associated web-based search program (http://bisscat.org/) can be used to find compounds containing selected combinations of substructures and functional groups. It can be used to determine possible additional substrates for known enzymes and for putative enzymes found in genome projects. Its applications to enzyme inhibitor design are also discussed
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