1,367 research outputs found
Pennsylvanian Stratigraphy in the Southern Wasatch Mountains, Utah
The area under consideration has a dimension of 8 miles east-west and 4 miles north-south, and includes the canyons of Spring Creek and Hobble Creek, Utah County, Utah. These streams flow off the west flank of a southern portion of the Wasatch Range, and have cut canyons to a depth of over 3,000 feet, exposing sections of upper Paleozoic sediments. Pennsylvanian rocks in the vicinity of the southern Wasatch Mountains have received little attention from stratigraphers. In this paper an attempt is made to describe the sequence of Pennsylvanian rocks in the region
Lumen formation by epithelial cell lines in response to collagen overlay: a morphogenetic model in culture.
Magnetothermal instability in laser plasmas including hydrodynamic effects
The impact of both density gradients and hydrodynamics on the evolution of the field compressing magnetothermal instability is considered [J. J. Bissell et al., Phys. Rev. Lett. 105, 175001 (2010)]. Hydrodynamic motion is found to have a limited effect on overall growth-rates; however, density gradients are shown to introduce an additional source term corresponding to a generalised description of the field generating thermal instability [D. Tidman and R. Shanny, Phys. Fluids 17, 1207 (1974)]. The field compressing and field generating source terms are contrasted, and the former is found to represent either the primary or sole instability mechanism for a range of conditions, especially those with Hall parameter v > 101. The generalised theory is compared to numerical simulation in the context of a recent nano-second gas-jet experiment [D. H. Froula et al., Phys. Rev. Lett. 98, 135001 (2007)] and shown to be in good agreement: exhibiting peak growth-rates and wavelengths of order 10 ns1 and 50 lm, respectively. The instabilityâs relevance to other experimental conditions, including those in inertial confinement fusion (I.C.F.) hohlraums, is also discussed
Nuclear spins, magnetic moments and quadrupole moments of Cu isotopes from N = 28 to N = 46: probes for core polarization effects
Measurements of the ground-state nuclear spins, magnetic and quadrupole
moments of the copper isotopes from 61Cu up to 75Cu are reported. The
experiments were performed at the ISOLDE facility, using the technique of
collinear laser spectroscopy. The trend in the magnetic moments between the
N=28 and N=50 shell closures is reasonably reproduced by large-scale
shell-model calculations starting from a 56Ni core. The quadrupole moments
reveal a strong polarization of the underlying Ni core when the neutron shell
is opened, which is however strongly reduced at N=40 due to the parity change
between the and orbits. No enhanced core polarization is seen beyond
N=40. Deviations between measured and calculated moments are attributed to the
softness of the 56Ni core and weakening of the Z=28 and N=28 shell gaps.Comment: 13 pagers, 19 figures, accepted by Physical Review
Decay-assisted collinear resonance ionization spectroscopy: Application to neutron-deficient francium
This paper reports on the hyperfine-structure and radioactive-decay studies
of the neutron-deficient francium isotopes Fr performed with the
Collinear Resonance Ionization Spectroscopy (CRIS) experiment at the ISOLDE
facility, CERN. The high resolution innate to collinear laser spectroscopy is
combined with the high efficiency of ion detection to provide a
highly-sensitive technique to probe the hyperfine structure of exotic isotopes.
The technique of decay-assisted laser spectroscopy is presented, whereby the
isomeric ion beam is deflected to a decay spectroscopy station for alpha-decay
tagging of the hyperfine components. Here, we present the first
hyperfine-structure measurements of the neutron-deficient francium isotopes
Fr, in addition to the identification of the low-lying states of
Fr performed at the CRIS experiment.Comment: Accepted for publication with Physical Review
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Evaluating the Patient-Reported Outcomes Measurement Information System scales in acute intermittent porphyria.
PurposeAcute intermittent porphyria (AIP) is a rare inborn error of heme biosynthesis characterized by life-threatening acute attacks. Few studies have assessed quality of life (QoL) in AIP and those that have had small sample sizes and used tools that may not have captured important domains.MethodsBaseline data from the Porphyrias Consortium's Longitudinal Study were obtained for 259 patients, including detailed disease and medical history data, and the following Patient-Reported Outcomes Measurement Information System (PROMIS) scales: anxiety, depression, pain interference, fatigue, sleep disturbance, physical function, and satisfaction with social roles. Relationships between PROMIS scores and clinical and biochemical AIP features were explored.ResultsPROMIS scores were significantly worse than the general population across all domains, except depression. Each domain discriminated well between asymptomatic and symptomatic patients with symptomatic patients having worse scores. Many important clinical variables like symptom frequency were significantly associated with domain scores in univariate analyses, showing responsiveness of the scales, specifically pain interference and fatigue. However, most regression models only explained ~20% of the variability observed in domain scores.ConclusionPain interference and fatigue were the most responsive scales in measuring QoL in this AIP cohort. Future studies should assess whether these scales capture longitudinal disease progression and treatment response
Laser spectroscopy of francium isotopes at the borders of the region of reflection asymmetry
The magnetic dipole moments and changes in mean-square charge radii of the
neutron-rich isotopes were measured with the
newly-installed Collinear Resonance Ionization Spectroscopy (CRIS) beam line at
ISOLDE, CERN, probing the to atomic
transition. The values for
and follow the observed increasing
slope of the charge radii beyond . The charge radii odd-even
staggering in this neutron-rich region is discussed, showing that
has a weakly inverted odd-even staggering while
has normal staggering. This suggests that both isotopes
reside at the borders of a region of inverted staggering, which has been
associated with reflection-asymmetric shapes. The value supports a shell model configuration for the
ground state. The values support the tentative
spin, and point to a intruder ground state configuration.Comment: Accepted for publication with Physical Review
Control of mammary epithelial differentiation: basement membrane induces tissue-specific gene expression in the absence of cell-cell interaction and morphological polarity.
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