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Aggregating Temporal Forensic Data Across Archival Digital Media
In this paper, I introduce a method for generating an aggregated timeline of file system activity derived from the disk images of archival digital media. Using a collection of 1,059 floppy disks from the Woody and Steina Vasulka collection as a case study for this process, I evaluate the technical issues of the dataset and describe the variances in date and time use for different file systems and the operating systems that use them. I discuss the utility of the timeline as a research and archival aid, and conclude that such timelines are promising resources which can provide a wider evaluative context for collections of digital media
Material choices for fibre in the Neolithic: an approach through the measurement of mechanical properties
Studies of the Mesolithic-Neolithic transition in Europe have focused on plants and animals exploited for food. However, the exploitation of plants for fibres underwent a significant change with the addition of domestic flax as a fibre crop. While the technology of flax fibre processing is increasingly understood by archaeologists, its material value as a fibre crop in comparison to indigenous fibre is less well explored. We examine the mechanical properties of flax and two indigenous fibres (lime bast, willow bast), by testing fibre strips for tensile properties and discuss the results in the light of material choices in these periods
Spatial variability of void structure in thin stochastic fibrous materials
Theory is presented for the distributions of local process intensity and
local average pore dimensions in random fibrous materials. For complete
partitioning of the network into contiguous square zones, the variance of local
process intensity is shown to be proportional to the mean process intensity and
inversely proportional to the zone size. The coefficient of variation of local
average pore area is shown to be approximately double that of the local average
pore diameter with both properties being inversely proportional to the square
root of zone size and mean process intensity. The results have relevance to
heterogenous near-planar fibrous materials including paper, nonwoven textiles,
nanofibrous composites and electrospun polymer fibre networks.Comment: 15 pages, 7 figure
The intracellular control of cholesterol metabolism
The liver has a major role in the metabolism of cholesterol, being
the main site of lipoprotein assembly and degradation and the only
tissue where the metabolism of cholesterol to bile acids occurs.
This provides the major pathway for the removal of cholesterol from
the body.The results described in this thesis concern the use of specific
enzyme inhibitors (58-035, Azacholesterol, Mevinolin) to determine
the intracellular use of different sources of cholesterol in
monolayers of rat hepatocytes. In particular, the fates of newly
synthesized cholesterol from mevalonic acid and cholesterol derived
from HDL2 were investigated.Incubation of hepatocyte monolayers with 58-035 resulted in the
inhibition of esterification. In the presence of mevalonic acid as
a cholesterol source, 58-035 stimulated bile acid synthesis.
Azacholesterol inhibited bile acid synthesis, had no effect on
cholesterol synthesis, and in the presence of mevalonic acid,
stimulated secretion of cholesterol by the hepatocytes; it had no
effect on cholesterol esterification. Mevinolin inhibited
cholesterol synthesis and as a result inhibited esterification.
HDL2, in the presence of mevinolin, was used as a cholesterol
source. It stimulated bile acid synthesis and cholesterol
esterification. Addition of 58-035 to the system resulted in the
inhibition of both esterification and bile acid synthesis. Overall,
the results indicated that different intracllular pools of free
cholesterol exist and that the inter-relationships of these pools
give a complex pattern of flux of intracellular cholesterol between
various pathways in the rat hepatocyte
Brief Sketches of the Early History of Lawrence University
William Harkness Sampson (1808-1902) was Principal and the primary financial agent of Lawrence University from the beginning of classes in 1849 until1853, during the time that the institution operated only as a preparatory school. He came to the Wisconsin Territory in 1842, where he worked as a Methodist minister. He was named Presiding Elder of the Green Bay Mission District in 1844. While serving in this position, he was approached by Amos Lawrence’s agents and became involved in the founding of Lawrence Institute. Following his resignation as principal and agent in 1853, he was a faculty member for several years longer and served on the Board of Trustees until 1884. The date of his written account of the early history of Lawrence is unknown.https://lux.lawrence.edu/archives_selections/1003/thumbnail.jp
Macromolecular crowding in chiral assembly of ellipsoidal nanoparticles
Anisotropic colloidal particles have the ability to self-assemble into
cholesteric structures. We used molecular dynamics to simulate the
self-assembly of ellipsoidal particles with the objective to establish a
general framework to reveal the primary factors driving chiral interactions. To
characterize these interactions, we introduce a characteristic parameter
following the crowding factor (CF) theory. Our simulations and statistical
analysis showed good agreement with the CF theory; at the early stages of the
assembly process, the ellipsoidal particles go through a critical aggregation
point followed by further clustering towards nematic order. Further, we
demonstrate that in high CF conditions, small initial clusters may induce a
chiral twist which subsequently forms a cholesteric structure with no
directional preference in higher organization states.Comment: Manuscript 8 pages, 5 Figures. Supporting information 3 Pages 5 SI
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Stress transfer in microfibrillated cellulose reinforced poly(vinyl alcohol) composites
Copyright © 2014 Elsevier. NOTICE: this is the author’s version of a work that was accepted for publication in Composites Part A: Applied Science and Manufacturing. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Composites Part A: Applied Science and Manufacturing Vol. 65 (2014), DOI: 10.1016/j.compositesa.2014.06.014Combined homogenisation and sonication treatments of micron-sized lyocell fibres were used to generate microfibrillated cellulose (MFC) with fibril diameters of ∼350 nm. No further reduction in fibril diameter was observed after 30 min treatment. Poly(vinyl alcohol) (PVA) composites reinforced with these fibrils were fabricated using solvent casting and physical and mechanical properties were investigated. The presence of MFC in PVA increased the thermal degradation of the polymer. An increase in both the tensile strength and modulus of the composites was observed for up to 3 wt.% of fibrils; beyond this point no significant increases were observed. An estimate of ∼39 GPa is made for the fibril modulus based on this increase. Stress-transfer between the polymer resin and the fibrils was investigated using Raman spectroscopy. Stress transfer in the composite is shown to be greater than that of a pure network of fibres, indicating a good fibre–matrix bond.Royal Thai Governmen
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