1,120 research outputs found
A Space Weather and Terrestrial Hazards Experiment for the MSTI Program
This paper discusses the instrumentation being built under BMDO auspices to construct a small, lightweight, low-cost satellite that provides measurements of local hazards affecting satellites in low-Earth orbit. In the following, we describe the objectives of the mission, the instrumentation being built and the mission profile for acquisition and utilization of the data products
Beta-delayed-neutron studies of Sb and I performed with trapped ions
Beta-delayed-neutron (n) spectroscopy was performed using the
Beta-decay Paul Trap and an array of radiation detectors. The n
branching ratios and energy spectra for Sb and I were
obtained by measuring the time of flight of recoil ions emerging from the
trapped ion cloud. These nuclei are located at the edge of an isotopic region
identified as having n branching ratios that impact the r-process
abundance pattern around the A~130 peak. For Sb and I,
n branching ratios of 14.6(11)%, 17.6(28)%, and 7.6(28)% were
determined, respectively. The n energy spectra obtained for Sb
and I are compared with results from direct neutron measurements, and
the n energy spectrum for Sb has been measured for the first
time
Persistent Chlamydophila pneumoniae infection in thoracic aortic aneurysm and aortic dissection?
The Drosophila tango gene encodes a bHLH-PAS protein that is orthologous to mammalian Arnt and controls CNS midline and tracheal development
The Drosophila single-minded and trachealess bHLH-PAS genes control transcription and development of the CNS midline cell lineage and tracheal tubules, respectively. We show that Single-minded and Trachealess activate transcription by forming dimers with the Drosophila Tango protein that is an orthologue of the mammalian Arnt protein. Both cell culture and in vivo studies show that a DNA enhancer element acts as a binding site for both Single-minded::Tango and Trachealess::Tango heterodimers and functions in controlling CNS midline and tracheal transcription. Isolation and analysis of tango mutants reveal CNS midline and tracheal defects, and gene dosage studies demonstrate in vivo interactions between single-minded::tango and trachealess::tango. These experiments support the existence of an evolutionarily conserved, functionally diverse bHLH-PAS protein regulatory system
Low-lying level structure of Cu and its implications on the rp process
The low-lying energy levels of proton-rich Cu have been extracted
using in-beam -ray spectroscopy with the state-of-the-art -ray
tracking array GRETINA in conjunction with the S800 spectrograph at the
National Superconducting Cyclotron Laboratory at Michigan State University.
Excited states in Cu serve as resonances in the
Ni(p,)Cu reaction, which is a part of the rp-process in
type I x-ray bursts. To resolve existing ambiguities in the reaction Q-value, a
more localized IMME mass fit is used resulting in ~keV. We derive
the first experimentally-constrained thermonuclear reaction rate for
Ni(p,)Cu. We find that, with this new rate, the
rp-process may bypass the Ni waiting point via the Ni(p,)
reaction for typical x-ray burst conditions with a branching of up to
40. We also identify additional nuclear physics uncertainties that
need to be addressed before drawing final conclusions about the rp-process
reaction flow in the Ni region.Comment: 8 pages, accepted for Phys. Rev.
Normal calcium-activated anion secretion in a mouse selectively lacking TMEM16A in intestinal epithelium
Calcium-activated anion secretion is expected to ameliorate cystic fibrosis, a genetic disease that carries an anion secretory defect in exocrine tissues. Human patients and animal models of the disease that present a mild intestinal phenotype have been postulated to bear a compensatory calcium-activated anion secretion in the intestine. TMEM16A is calcium-activated anion channel whose presence in the intestinal epithelium is contradictory. We aim to test the functional expression of TMEM16A using animal models with Cftr and/or Tmem16a intestinal silencing. Expression of TMEM16A was studied in a wild type and intestinal Tmem16a knockout mice by mRNA-seq, mass-spectrometry, q-PCR, Western blotting and immunolocalization. Calcium-activated anion secretion was recorded in the ileum and proximal colon of these animals including intestinal Cftr knockout and double mutants with dual Tmem16a and Cftr intestinal ablation. Mucus homeostasis was studied by immune-analysis of Mucin-2 (Muc2) and survival curves were recorded. Tmem16a transcript was found in intestine. Nevertheless, protein was barely detected in colon samples. Electrophysiological measurements demonstrated that the intestinal deletion of Tmem16a did not change calcium-activated anion secretion induced by carbachol or ATP in ileum and proximal colon. Muc2 architecture was not altered by Tmem16a silencing as was observed when Cftr was deleted from mouse intestine. Tmem16a silencing neither affected animal survival nor modified the lethality observed in the intestinal Cftr-null mouse. Our results demonstrate that TMEM16A function in the murine intestine is not related to electrogenic calcium-activated anion transport and does not affect mucus homeostasis and survival of animals
Thermodynamic theory of epitaxial ferroelectric thin films with dense domain structures
A Landau-Ginsburg-Devonshire-type nonlinear phenomenological theory is
presented, which enables the thermodynamic description of dense laminar
polydomain states in epitaxial ferroelectric thin films. The theory explicitly
takes into account the mechanical substrate effect on the polarizations and
lattice strains in dissimilar elastic domains (twins). Numerical calculations
are performed for PbTiO3 and BaTiO3 films grown on (001)-oriented cubic
substrates. The "misfit strain-temperature" phase diagrams are developed for
these films, showing stability ranges of various possible polydomain and
single-domain states. Three types of polarization instabilities are revealed
for polydomain epitaxial ferroelectric films, which may lead to the formation
of new polydomain states forbidden in bulk crystals. The total dielectric and
piezoelectric small-signal responses of polydomain films are calculated,
resulting from both the volume and domain-wall contributions. For BaTiO3 films,
strong dielectric anomalies are predicted at room temperature near special
values of the misfit strain.Comment: 19 pages, 8 figure
A 12-month follow-up of a mobile-based (mHealth) obesity prevention intervention in pre-school children: the MINISTOP randomized controlled trial
Background: To date, few mobile health (mHealth) interventions aimed at changing lifestyle behaviors have
measured long term effectiveness. At the 6-month follow-up the MINISTOP trial found a statistically significant
intervention effect for a composite score comprised of fat mass index (FMI) as well as dietary and physical activity
variables; however, no intervention effect was observed for FMI. Therefore, the aim of this study was to investigate
if the MINISTOP intervention 12-months after baseline measurements: (i) improved FMI and (ii) had a maintained
effect on a composite score comprised of FMI and dietary and physical activity variables.
Methods: A two-arm parallel randomized controlled trial was conducted in 315 healthy 4.5 year old children
between January 2014 and October 2015. Parents’ of the participating children either received the MINISTOP
intervention or a basic pamphlet on dietary and physical activity behaviors (control group). After 6 months,
participants did not have access to the intervention content and were measured again 6 months later (i.e. the
12-month follow-up). The Wilcoxon rank-sum test was then used to examine differences between the groups.
Results: At the 12-month follow-up, no statistically significant difference was observed between the intervention
and control groups for FMI (p = 0.57) and no maintained effect for the change in composite score was observed
(mean ± standard deviation for the intervention and control group: + 0.53 ± 1.49 units and + 0.35 ± 1.27 units
respectively, p = 0.25 between groups).
Conclusions: The intervention effect observed at the 6-month follow-up on the composite score was not
maintained at the 12-month follow-up, with no effect on FMI being observed at either follow-up. Future studies
using mHealth are needed to investigate how changes in obesity related markers in young children can be
maintained over longer time periods.The MINISTOP project was funded by the Swedish Research Council (project
no. 2012–2883), the Swedish Research Council for Health, Working Life and
Welfare (2012–0906), Bo and Vera Axson Johnsons Foundation, and
Karolinska Institutet (M.L.). C.D.N was supported by the Swedish Nutrition
Foundation and S.S was funded by the Seaver Foundation. None of the
funding bodies had any contributions or influence in the design of the
study, data collection, analysis, interpretation of the data, or the writing of
the manuscript
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