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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
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
Studies of Salt Water intrusion in Opobo/Nkoro Rivers State Using Geophysical and Hydrochemical Methods
Salt water intrusions into fresh water aquifers in Opobo town in Nkoro L.G.A, Rivers state is becoming an issue of concern to the community, and as such requires detailed analysis through an integration of qualitative (geo-electric) and quantitative (hydrochemical) methods. Twenty vertical electrical soundings (VES) labelled as O/MSC/01 to O/MSC/20 and three 2D electrical resistivity tomography (ERT) data were acquired in the area. Results from interpretation of the twenty VES profiles showed 4 geo-electric layers, which are topsoil, sand, sandy clay and clay. In VES geo-electric sections, it was observed that salt intrusions occur at depths of 43.135m, 55.20m, 43.528m, 51.63m, and 28.357m along O/MSC/02, O/MSC/05, O/MSC/07, O/MSC/11 and O/MSC/15 profiles respectively. No salt intrusion was observed in O/MSC/01, O/MSC/04, O/MSC/09, O/MSC/10, O/MSC/12 and O/MSC/14 within the depth investigated. Results of 2D imaging along VES profiles 10, 11 and 12, show salt intrusions observed along the three profiles at different depths within the subsurface. Along profile O/MSC/10, saltwater intrusions (with resistivity range of 59.2Ωm-60.1Ωm) was observed at depth of 7.59-9.59m at lateral distance of 34.0-36.0m and depth of 5.59-7.59m at lateral distance of 94-96m. Along profile O/MSC/11 salt intrusions (with resistivity range of 58.8Ωm-59.2Ωm) was observed at depth of 2.59-5.59m at lateral distance of 28-40m, and 110-128m, while along profile O/MSC/12 salt intrusions (with resistivity range of 14.5-20Ωm) was observed at depth of 3.59-5.59m at lateral distance of 112-118m. These findings were not observed in VES surveys along similar profiles where 2D ERT was carried out. 3D map computed to connect aquifers within the third geo-electric layers for VES points 1-20, showed that within the third geo-electric layers for O/MSC/02, 05, 07, 11, 16, 17, and 20 lies saline water. The reliability of these results was validated by results from quantitative assessment of physiochemical parameters (PH, electrical conductivity (EC), and total hardness) and hydrochemical contents (HCO3-, Na+, K+, CL-, and SO42-) used to evaluate the ionic abundance of water samples taken from seven wells/boreholes in the area. PH values of 6.40-6.90 were predominant in the samples which indicates slight acidity and unsuitable for human consumption, EC values in the order of 1705μS/cm, & 1853.74μS/cm were obtained and total dissolved Solids (TDS) was in the order of 700.30mg/l & 750.02mg/l. Elevated EC values in water is indicative of high ionic abundance, and is diagnostic to salinity of the water as reflected in the 1D and 2D geo-electric surveys. However, the study area also contains fresh water aquifers lying within the third geo-electric layers for VES profiles O/MSC/01, 03, 06, 08, 09, 10, 12, and 18, hence a water supply tube well can be drilled in these areas for groundwater production but the water should be subjected to hydrochemical test to ascertain its level of contamination and prior treatments before human consumption. Keywords: Saltwater Intrusion, Groundwater, Vertical electrical sounding (VES), Electrical resistivity tomography (ERT), Geo-electric section
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