419 research outputs found
High- Elastic -scattering and QCD predictions
In the framework of pertubative QCD it is argued that in the elastic
-scattering at few the light-cone-frame
helicity-flip amplitudes could not be omitted. The obtained ratio
of Rosenbluth structure functions is shown to be in a good agreement with
experimental data. The high behavior of tensor analysing power
is discussed.Comment: 6 pages + 2 ps figures not included, LaTeX, ITP-93-33
Developing a design-based concept to improve hand hygiene in the neonatal intensive care unit
BackgroundHand hygiene (HH) is the most critical measure in the prevention of nosocomial infections in the neonatal intensive care unit (NICU). Improving and sustaining adequate HH compliance rates, however, remains a significant challenge. Using a behavioral change framework and nudge theory, we developed a design-based concept aimed at facilitating and stimulating HH behavior.MethodsConcept development was initiated by selecting a theoretical framework after which contextual field studies aimed at discovering causes for poor compliance were conducted. Potential solutions were brainstormed upon during focus group sessions. Low-fidelity prototypes were tested regarding feasibility, usability, and acceptability. A final concept was crafted drawing from findings from each design phase.ResultsComplying with recommended HH guidelines is unrealistic and infeasible due to frequent competing (clinical) priorities requiring HH. The concept "Island-based nursing," where a patient room is divided into two geographical areas, namely, the island and general zone, was created. HH must be performed upon entering and exiting the island zone, and after exposure to any surface within the general zone. Reminding of HH is prompted by illuminated demarcation of the island zone, serving as the concept's nudge.ConclusionsIsland zone demarcation facilitates and economizes HH indications in an innovative and intuitive manner.ImpactAlthough hand hygiene (HH) is the single most important element in the prevention of nosocomial infections in neonates, improving and sustaining adequate HH compliance rates remains a significant challenge.Complying with recommended HH guidelines was found to be unrealistic and infeasible due to the significant amount of time required for HH in a setting with a high workload and many competing (clinical) priorities.The concept of "Island-based nursing," under which the primary HH indication is upon entering and exiting the island zone, facilitates and economizes HH indications in an innovative and user-friendly manner.Developmen
NanoBiT System and Hydrofurimazine for Optimized Detection of Viral Infection in Mice-A Novel in Vivo Imaging Platform.
Reporter genes are used to visualize intracellular biological phenomena, including viral infection. Here we demonstrate bioluminescent imaging of viral infection using the NanoBiT system in combination with intraperitoneal injection of a furimazine analogue, hydrofurimazine. This recently developed substrate has enhanced aqueous solubility allowing delivery of higher doses for in vivo imaging. The small high-affinity peptide tag (HiBiT), which is only 11 amino-acids in length, was engineered into a clinically used oncolytic adenovirus, and the complementary large protein (LgBiT) was constitutively expressed in tumor cells. Infection of the LgBiT expressing cells with the HiBiT oncolytic virus will reconstitute NanoLuc in the cytosol of the cell, providing strong bioluminescence upon treatment with substrate. This new bioluminescent system served as an early stage quantitative viral transduction reporter in vitro and also in vivo in mice, for longitudinal monitoring of oncolytic viral persistence in infected tumor cells. This platform provides novel opportunities for studying the biology of viruses in animal models
Generation of LUMCi041-A-2: equipping a PAX3 reporter iPSC line with doxycycline inducible H2B-mTurquoise2 for live cell imaging
An induced pluripotent stem cell (iPSC) line, in which a H2B-fluorescent protein fusion is temporally expressed, is a valuable tool to track cells and study cell divisions and apoptosis. To this end we introduced a 3rd generation "all-in-one" doxycycline-inducible H2B-mTurquoise2 vector into the AAVS1 locus of PAX3-Venus iPSCs via CRISPR/Cas9. H2B-mTurquoise2 expression is absent but readily induced by doxycycline allowing quantification of cell divisions and imaging of living cells. Besides being a universal reporter in iPSC-based differentiation and toxicity assays, the generated pluripotent and genomically normal LUMCi041-A-2 line is particularly suited to study PAX3-positive stages of development.Therapeutic cell differentiatio
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Hazard ranking system evaluation of CERCLA inactive waste sites at Hanford: Volume 3: Unplanned-release sites (HISS data base)
The purpose of this report is to formally document the assessment activities at the US Department of Energy (DOE) Hanford Site. These activities were carried out pursuant to the DOE orders that address the Comprehensive Environmental Response, and Liability Act (CERCLA) Program for the cleanup of inactive waste sites. The DOE orders incorporate the US Environmental Protection Agency methodology, which is based on the Superfund Amendments and Reauthorization Act of 1986. This methodology includes:PA/SI, remedial investigation/feasibility study, record of decision, design and implementation or remedial action, operation and monitoring, and verification monitoring. Volume 1 of this report discusses the CERCLA inactive waste-site evaluation process, assumptions, and results of the Hazard Ranking System methodology employed. Volume 2 presents the data on the individual CERCLA engineered-facility sites at Hanford, as contained in the Hanford Inactive Site Surveillance (HISS) Data Base. Volume 3 presents the data on the individual CERCLA unplanned-release sites at Hanford, as contained in the HISS Data Base. 13 figs
The Glauber model and the heavy ion reaction cross section
We reexamine the Glauber model and calculate the total reaction cross section
as a function of energy in the low and intermediate energy range, where many of
the corrections in the model, are effective.
The most significant effect in this energy range is by the modification of
the trajectory due to the Coulomb field. The modification in the trajectory due
to nuclear field is also taken into account in a self consistent way.
The energy ranges in which particular corrections are effective, are
quantified and it is found that when the center of mass energy of the system
becomes 30 times the Coulomb barrier, none of the trajectory modification to
the Glauber model is really required.
The reaction cross sections for light and heavy systems, right from near
coulomb barrier to intermediate energies have been calculated. The exact
nuclear densities and free nucleon-nucleon (NN) cross sections have been used
in the calculations. The center of mass correction which is important for light
systems, has also been taken into account.
There is an excellent agreement between the calculations with the modified
Glauber model and the experimental data. This suggests that the heavy ion
reactions in this energy range can be explained by the Glauber model in terms
of free NN cross sections without incorporating any medium modification.Comment: RevTeX, 21 pages including 9 Postscript figures, submitted to Phys.
Rev.
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Corrosion behavior of rebar for intermittent cathodic protection of coastal bridges
A number of reinforced concrete bridges on the Oregon coast are protected against chloride-induced corrosion damage by means of impressed current cathodic protection (ICCP). Thermal-sprayed Zn serves as the anode in these systems. Rebar in the concrete can remain passive and protected for some period of time after the CP system is turned off. The active-passive corrosion behavior of rebar in simulated pore solution (SPS) was investigated as a function of pH and Cl- concentration as part of a study of intermittent ICCP operation. Rebar corrosion rates in SPS were determined from polarization curves by fitting the Butler-Volmer equation and the linear polarization equation. Analysis of the passive film in SPS by x-ray diffraction and surface enhanced Raman spectroscopy showed it to be largely Fe3O4. However, the Fe(OH)2 content increased with cathodic polarization time
Rebirth of X-ray Emission from the Born-Again Planetary Nebula A 30
The planetary nebula (PN) A30 is believed to have undergone a very late
thermal pulse resulting in the ejection of knots of hydrogen-poor material.
Using HST images we have detected the angular expansion of these knots and
derived an age of 850+280-150 yr. To investigate the spectral and spatial
properties of the soft X-ray emission detected by ROSAT, we have obtained
Chandra and XMM-Newton observations of A30. The X-ray emission from A30 can be
separated into two components: a point-source at the central star and diffuse
emission associated with the hydrogen-poor knots and the cloverleaf structure
inside the nebular shell. To help us assess the role of the current stellar
wind in powering this X-ray emission, we have determined the stellar parameters
of the central star of A 30 using a non-LTE model fit to its optical and UV
spectrum. The spatial distribution and spectral properties of the diffuse X-ray
emission is suggestive that it is generated by the post-born-again and present
fast stellar winds interacting with the hydrogen-poor ejecta of the born-again
event. This emission can be attributed to shock-heated plasma, as the
hydrogen-poor knots are ablated by the stellar winds, under which circumstances
the efficient mass-loading of the present fast stellar wind raises its density
and damps its velocity to produce the observed diffuse soft X-rays. Charge
transfer reactions between the ions of the stellar winds and material of the
born-again ejecta has also been considered as a possible mechanism for the
production of diffuse X-ray emission, and upper limits on the expected X-ray
production by this mechanism have been derived. The origin of the X-ray
emission from the central star of A 30 is puzzling: shocks in the present fast
stellar wind and photospheric emission can be ruled out, while the development
of a new, compact hot bubble confining the fast stellar wind seems implausible.Comment: 29 pages, 11 figures, 4 tables; accepted for publication by Ap
Nonhuman primate adenoviruses of the human adenovirus B species are potent and broadly acting oncolytic vector candidates
The use of human adenoviruses (hAds) as oncolytic agents has demonstrated considerable potential. However, their efficacy in clinical studies is generally moderate and often varies between patients. This may, in part, be attributable to variable pre-existing neutralizing immunity in patients, which can impact the antitumor efficacy and lead to response heterogeneity. Our aim was to isolate new Ads for the development of oncolytic vectors with low prevalence of neutralizing immunity in the human population. To this end, we isolated a collection of new nonhuman primate (nhp) Ads from stool samples of four great ape species held captive. We elected 12 isolates comprising the broadest genetic variability for further characterization. For three new nhpAds, all classified as the human adenovirus B (HAdV-B) species, no neutralizing activity could be detected when exposed to a preparation of immunoglobulins isolated from a pool of >1,000 donors as a surrogate of population immunity. In addition, the nhpAds of the HAdV-B species showed enhanced oncolytic potency compared to nhpAds of the HAdV-C species as well as to human adenovirus type 5 (HAdV-C5) in vitro when tested in a panel of 29 human cancer cell lines. Next-generation sequencing of the viral genomes revealed higher sequence similarity between hAds and nhpAds of HAdV-B compared to HAdV-C, which might underlie the differences in oncolytic ability. As a proof-of-concept, the Rb-binding domain of the E1A protein of the gorilla-derived HAdV-B nhpAd-lumc007 was deleted, thereby creating a new oncolytic derivative, which demonstrated increased oncolytic potential compared to HAdV-C5. Collectively, our data demonstrate that nhpAds of the HAdV-B species can serve as an alternative for the development of potent oncolytic Ad vectors with limited pre-existing neutralizing immunity in humans.Therapeutic cell differentiatio
Elastic electron deuteron scattering with consistent meson exchange and relativistic contributions of leading order
The influence of relativistic contributions to elastic electron deuteron
scattering is studied systematically at low and intermediate momentum transfers
( fm). In a -expansion, all leading order
relativistic -exchange contributions consistent with the Bonn OBEPQ models
are included. In addition, static heavy meson exchange currents including boost
terms and lowest order -currents are considered. Sizeable
effects from the various relativistic two-body contributions, mainly from
-exchange, have been found in form factors, structure functions and the
tensor polarization . Furthermore, static properties, viz. magnetic
dipole and charge quadrupole moments and the mean square charge radius are
evaluated.Comment: 15 pages Latex including 5 figures, final version accepted for
publication in Phys.Rev.C Details of changes: (i) The notation of the curves
in Figs. 1 and 2 have been clarified with respect to left and right panels.
(ii) In Figs. 3 and 4 an experimental point for T_20 has been added and a
corresponding reference [48] (iii) At the end of the text we have added a
paragraph concerning the quality of the Bonn OBEPQ potential
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