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618-10 Burial Ground Trench Remediation and 618-10 and 618-11 Burial Ground Nonintrusive Characterization of Vertical Pipe Units Lessons Learned
A “lessons learned” is a noteworthy practice or innovative approach that is captured and shared to promote repeat application, or an adverse work practice/experience that is captured and shared to avoid reoccurrence. This document provides the lessons learned identified by the 618-10 Burial Ground trench remediation and the 618-10 and 618-11 Burial Ground nonintrusive characterization of the vertical pipe units (VPUs)
Characterization of Pro-Inflammatory Flagellin Proteins Produced by Lactobacillus ruminis and Related Motile Lactobacilli
peer-reviewedLactobacillus ruminis is one of at least twelve motile but poorly characterized species found in the genus Lactobacillus. Of these, only L. ruminis has been isolated from mammals, and this species may be considered as an autochthonous member of the gastrointestinal microbiota of humans, pigs and cows. Nine L. ruminis strains were investigated here to elucidate the biochemistry and genetics of Lactobacillus motility. Six strains isolated from humans were non-motile while three bovine isolates were motile. A complete set of flagellum biogenesis genes was annotated in the sequenced genomes of two strains, ATCC25644 (human isolate) and ATCC27782 (bovine isolate), but only the latter strain produced flagella. Comparison of the L. ruminis and L. mali DSM20444T motility loci showed that their genetic content and gene-order were broadly similar, although the L. mali motility locus was interrupted by an 11.8 Kb region encoding rhamnose utilization genes that is absent from the L. ruminis motility locus. Phylogenetic analysis of 39 motile bacteria indicated that Lactobacillus motility genes were most closely related to those of motile carnobacteria and enterococci. Transcriptome analysis revealed that motility genes were transcribed at a significantly higher level in motile L. ruminis ATCC27782 than in non-motile ATCC25644. Flagellin proteins were isolated from L. ruminis ATCC27782 and from three other Lactobacillus species, while recombinant flagellin of aflagellate L. ruminis ATCC25644 was expressed and purified from E. coli. These native and recombinant Lactobacillus flagellins, and also flagellate L. ruminis cells, triggered interleukin-8 production in cultured human intestinal epithelial cells in a manner suppressed by short interfering RNA directed against Toll-Like Receptor 5. This study provides genetic, transcriptomic, phylogenetic and immunological insights into the trait of flagellum-mediated motility in the lactobacilli.This work was supported by a Principal Investigator Award (07/IN.1/B1780) from Science Foundation Ireland to PWOT. BAN was the recipient of an Embark studentship from the Irish Research Council for Science Engineering and Technology. TD and KN were supported by the Alimentary Pharmabiotic Centre, funded by Science Foundation Ireland
Urban transportation: Perspectives on mobility and choice
A study of urban transportation systems are presented characterized by intensive scrutiny of many ideas, philosophies, and academic perspectives. This report is intended to communicate some dimensions of the urban transportation problem to the general public
Arctic ice export events and their potential impact on global climate during the late Pleistocene
Ice sheets in the North American Arctic and, to a lesser extent, those in northern Eurasia calved large
quantities of icebergs that drifted through Fram Strait into the Greenland Sea several times during the late
Pleistocene. These icebergs deposited Fe oxide grains (45–250 mm) and coarse lithic clasts >250 mm matched to
specific circum-Arctic sources. Four massive Arctic iceberg export events are identified from the Laurentide and
the Innuitian ice sheets, between 14 and 34 ka (calendar years) in a sediment core from Fram Strait. These
relatively short duration (<1–4 kyr) events contain 3–5 times the background levels of Fe oxide grains. They
began suddenly, as indicated by a steep rise in the number of grains matched to an ice sheet source, suggesting
rapid purges of ice through Fram Strait, due perhaps to collapse of ice sheets. The larger events from the
northwestern Laurentide ice sheet are preceded by events from the Innuitian ice sheet. Despite the chronological
uncertainties, the Arctic export events appear to occur prior to Heinrich events
In-gas-cell laser ionization spectroscopy in the vicinity of 100Sn: Magnetic moments and mean-square charge radii of N=50-54 Ag
In-gas-cell laser ionization spectroscopy studies on the neutron deficient
97-101Ag isotopes have been performed with the LISOL setup. Magnetic dipole
moments and mean-square charge radii have been determined for the first time
with the exception of 101Ag, which was found in good agreement with previous
experimental values. The reported results allow tentatively assigning the spin
of 97,99Ag to 9/2 and confirming the presence of an isomeric state in these two
isotopes, whose collapsed hyperfine structure suggests a spin of 1/2 . The
effect of the N=50 shell closure is not only manifested in the magnetic moments
but also in the evolution of the mean-square charge radii of the isotopes
investigated, in accordance with the spherical droplet model predictions
Boolean delay equations on networks: An application to economic damage propagation
We introduce economic models based on Boolean Delay Equations: this formalism
makes easier to take into account the complexity of the interactions between
firms and is particularly appropriate for studying the propagation of an
initial damage due to a catastrophe. Here we concentrate on simple cases, which
allow to understand the effects of multiple concurrent production paths as well
as the presence of stochasticity in the path time lengths or in the network
structure.
In absence of flexibility, the shortening of production of a single firm in
an isolated network with multiple connections usually ends up by attaining a
finite fraction of the firms or the whole economy, whereas the interactions
with the outside allow a partial recovering of the activity, giving rise to
periodic solutions with waves of damage which propagate across the structure.
The damage propagation speed is strongly dependent upon the topology. The
existence of multiple concurrent production paths does not necessarily imply a
slowing down of the propagation, which can be as fast as the shortest path.Comment: Latex, 52 pages with 22 eps figure
Nudges and other moral technologies in the context of power: Assigning and accepting responsibility
Strawson argues that we should understand moral responsibility in terms of our practices of holding responsible and taking responsibility. The former covers what is commonly referred to as backward-looking responsibility , while the latter covers what is commonly referred to as forward-looking responsibility . We consider new technologies and interventions that facilitate assignment of responsibility. Assigning responsibility is best understood as the second- or third-personal analogue of taking responsibility. It establishes forward-looking responsibility. But unlike taking responsibility, it establishes forward-looking responsibility in someone else. When such assignments are accepted, they function in such a way that those to whom responsibility has been assigned face the same obligations and are susceptible to the same reactive attitudes as someone who takes responsibility. One family of interventions interests us in particular: nudges. We contend that many instances of nudging tacitly assign responsibility to nudgees for actions, values, and relationships that they might not otherwise have taken responsibility for. To the extent that nudgees tacitly accept such assignments, they become responsible for upholding norms that would otherwise have fallen under the purview of other actors. While this may be empowering in some cases, it can also function in such a way that it burdens people with more responsibility that they can (reasonably be expected to) manage
Autologous chondrocyte implantation for cartilage repair: monitoring its success by magnetic resonance imaging and histology
Autologous chondrocyte implantation is being used increasingly for the treatment of cartilage defects. In spite of this, there has been a paucity of objective, standardised assessment of the outcome and quality of repair tissue formed. We have investigated patients treated with autologous chondrocyte implantation (ACI), some in conjunction with mosaicplasty, and developed objective, semiquantitative scoring schemes to monitor the repair tissue using MRI and histology. Results indicate repair tissue to be on average 2.5 mm thick. It was of varying morphology ranging from predominantly hyaline in 22% of biopsy specimens, mixed in 48%, through to predominantly fibrocartilage, in 30%, apparently improving with increasing time postgraft. Repair tissue was well integrated with the host tissue in all aspects viewed. MRI scans provide a useful assessment of properties of the whole graft area and adjacent tissue and is a noninvasive technique for long-term follow-up. It correlated with histology (P = 0.02) in patients treated with ACI alone
Mean-risk models using two risk measures: A multi-objective approach
This paper proposes a model for portfolio optimisation, in which distributions are characterised and compared on the basis of three statistics: the expected value, the variance and the CVaR at a specified confidence level. The problem is multi-objective and transformed into a single objective problem in which variance is minimised while constraints are imposed on the expected value and CVaR. In the case of discrete random variables, the problem is a quadratic program. The mean-variance (mean-CVaR) efficient solutions that are not dominated with respect to CVaR (variance) are particular efficient solutions of the proposed model. In addition, the model has efficient solutions that are discarded by both mean-variance and mean-CVaR models, although they may improve the return distribution. The model is tested on real data drawn from the FTSE 100 index. An analysis of the return distribution of the chosen portfolios is presented
Spanning Boundaries in an Arizona Watershed Partnership: Information Networks as Tools for Entrenchment or Ties for Collaboration?
The need to develop successful collaborative strategies is an enduring problem in sustainable resource management. Our goal is to evaluate the relationship between information networks and conflict in the context of collaborative groundwater management in the rapidly growing central highland region of Arizona. In this region, water-management conflicts have emerged because of stakeholders’ differing geographic perspectives and competing scientific claims. Using social network analyses, we explored the extent to which the Verde River Basin Partnership (VRBP), which was charged with developing and sharing scientific information, has contributed to collaboration in the region. To accomplish this, we examined the role that this stakeholder partnership plays in reinforcing or overcoming the geographic, ideological, expert, and power conflicts among its members. Focusing on information sharing, we tested the extent to which several theoretically important elements of successful collaboration were evidenced by data from the VRBP. The structure of information sharing provides insight into ways in which barriers between diverse perspectives might be retained and elucidates weaknesses in the partnership. To characterize information sharing, we examined interaction ties among individuals with different geographic concerns, hierarchical scales of interest, belief systems (about science, the environment, and the role of the partnership), and self-identified expertise types. Results showed that the partnership’s information-sharing network spans most of these boundaries. Based on current theories of collaboration, we would expect the partnership network to be conducive to collaboration. We found that information exchanges are limited by differences in connection patterns across actor expertise and environmental-belief systems. Actors who view scientists as advocates are significantly more likely to occupy boundary-spanning positions, that appear to impede the success of the partnership. This analysis challenges widely held assumptions about the properties that separate successful collaborations from those that are less successful. It has implications for our understanding of the factors that constrain information processing, knowledge production, and collective-action capability in institutions
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