10,640 research outputs found
Noise characterization of an atomic magnetometer at sub-millihertz frequencies
Noise measurements have been carried out in the LISA bandwidth (0.1 mHz to
100 mHz) to characterize an all-optical atomic magnetometer based on nonlinear
magneto-optical rotation. This was done in order to assess if the technology
can be used for space missions with demanding low-frequency requirements like
the LISA concept. Magnetometry for low-frequency applications is usually
limited by noise and thermal drifts, which become the dominant
contributions at sub-millihertz frequencies. Magnetic field measurements with
atomic magnetometers are not immune to low-frequency fluctuations and
significant excess noise may arise due to external elements, such as
temperature fluctuations or intrinsic noise in the electronics. In addition,
low-frequency drifts in the applied magnetic field have been identified in
order to distinguish their noise contribution from that of the sensor. We have
found the technology suitable for LISA in terms of sensitivity, although
further work must be done to characterize the low-frequency noise in a
miniaturized setup suitable for space missions.Comment: 11 pages, 12 figure
A pilot study of the S-MAP (Solutions for Medications Adherence Problems) intervention for older adults prescribed polypharmacy in primary care: Study protocol
Background: Adhering to multiple medications as prescribed is challenging for older patients (aged ≥ 65 years) and a difficult behaviour to improve. Previous interventions designed to address this have been largely complex in nature but have shown limited effectiveness and have rarely used theory in their design. It has been recognised that theory ('a systematic way of understanding events or situations') can guide intervention development and help researchers better understand how complex adherence interventions work. This pilot study aims to test a novel community pharmacy-based intervention that has been systematically developed using the Theoretical Domains Framework (12-domain version) of behaviour change. Methods: As part of a non-randomised pilot study, pharmacists in 12 community pharmacies across Northern Ireland (n = 6) and London, England (n = 6), will be trained to deliver the intervention to older patients who are prescribed ≥ 4 regular medicines and are non-adherent (self-reported). Ten patients will be recruited per pharmacy (n = 120) and offered up to four tailored one-to-one sessions, in the pharmacy or via telephone depending on their adherence, over a 3-4-month period. Guided by an electronic application (app) on iPads, the intervention content will be tailored to each patient's underlying reasons for non-adherence and mapped to the most appropriate solutions using established behaviour change techniques. This study will assess the feasibility of collecting data on the primary outcome of medication adherence (self-report and dispensing data) and secondary outcomes (health-related quality of life and unplanned hospitalisations). An embedded process evaluation will assess training fidelity for pharmacy staff, intervention fidelity, acceptability to patients and pharmacists and the intervention's mechanism of action. Process evaluation data will include audio-recordings of training workshops, intervention sessions, feedback interviews and patient surveys. Analysis will be largely descriptive. Discussion: Using pre-defined progression criteria, the findings from this pilot study will guide the decision whether to proceed to a cluster randomised controlled trial to test the effectiveness of the S-MAP intervention in comparison to usual care in community pharmacies. The study will also explore how the intervention components may work to bring about change in older patients' adherence behaviour and guide further refinement of the intervention and study procedures. Trial registration: This study is registered at ISRCTN: https://doi.org/10.1186/ISRCTN7383153
Palatable Meal Anticipation in Mice
The ability to sense time and anticipate events is a critical skill in nature. Most efforts to understand the neural and molecular mechanisms of anticipatory behavior in rodents rely on daily restricted food access, which induces a robust increase of locomotor activity in anticipation of daily meal time. Interestingly, rats also show increased activity in anticipation of a daily palatable meal even when they have an ample food supply, suggesting a role for brain reward systems in anticipatory behavior, and providing an alternate model by which to study the neurobiology of anticipation in species, such as mice, that are less well adapted to "stuff and starve" feeding schedules. To extend this model to mice, and exploit molecular genetic resources available for that species, we tested the ability of wild-type mice to anticipate a daily palatable meal. We observed that mice with free access to regular chow and limited access to highly palatable snacks of chocolate or “Fruit Crunchies” avidly consumed the snack but did not show anticipatory locomotor activity as measured by running wheels or video-based behavioral analysis. However, male mice receiving a snack of high fat chow did show increased food bin entry prior to access time and a modest increase in activity in the two hours preceding the scheduled meal. Interestingly, female mice did not show anticipation of a daily high fat meal but did show increased activity at scheduled mealtime when that meal was withdrawn. These results indicate that anticipation of a scheduled food reward in mice is behavior, diet, and gender specific
Induced superfluidity of imbalanced Fermi gases near unitarity
The induced intraspecies interactions among the majority species, mediated by
the minority species, is computed for a population-imbalanced two-component
Fermi gas. Although the Feshbach-resonance mediated interspecies interaction is
dominant for equal populations, leading to singlet s-wave pairing, we find that
in the strongly imbalanced regime the induced intraspecies interaction leads to
p-wave pairing and superfluidity of the majority species. Thus, we predict that
the observed spin-polaron Fermi liquid state in this regime is unstable to
p-wave superfluidity, in accordance with the results of Kohn and Luttinger,
below a temperature that, near unitarity, we find to be within current
experimental capabilities. Possible experimental signatures of the p-wave state
using radio-frequency spectroscopy as well as density-density correlations
after free expansion are presented.Comment: 15 pages, 13 figures, submitted to Phys. Rev.
A Hubble Space Telescope Snapshot Survey of Dynamically Close Galaxy Pairs in the CNOC2 Redshift Survey
We compare the structural properties of two classes of galaxies at
intermediate redshift: those in dynamically close galaxy pairs, and those which
are isolated. Both samples are selected from the CNOC2 Redshift Survey, and
have redshifts in the range 0.1 < z <0.6. Hubble Space Telescope WFPC2 images
were acquired as part of a snapshot survey, and were used to measure bulge
fraction and asymmetry for these galaxies. We find that paired and isolated
galaxies have identical distributions of bulge fractions. Conversely, we find
that paired galaxies are much more likely to be asymmetric (R_T+R_A >= 0.13)
than isolated galaxies. Assuming that half of these pairs are unlikely to be
close enough to merge, we estimate that 40% +/- 11% of merging galaxies are
asymmetric, compared with 9% +/- 3% of isolated galaxies. The difference is
even more striking for strongly asymmetric (R_T+R_A >= 0.16) galaxies: 25% +/-
8% for merging galaxies versus 1% +/- 1% for isolated galaxies. We find that
strongly asymmetric paired galaxies are very blue, with rest-frame B-R colors
close to 0.80, compared with a mean (B-R)_0 of 1.24 for all paired galaxies. In
addition, asymmetric galaxies in pairs have strong [OII]3727 emission lines. We
conclude that close to half of the galaxy pairs in our sample are in the
process of merging, and that most of these mergers are accompanied by triggered
star formation.Comment: Accepted for publication in the Astronomical Journal. 40 pages,
including 15 figures. For full resolution version, please see
http://www.trentu.ca/physics/dpatton/hstpairs
A Widespread, Clumpy Starburst in the Isolated Ongoing Dwarf Galaxy Merger dm1647+21
Interactions between pairs of isolated dwarf galaxies provide a critical
window into low-mass hierarchical, gas-dominated galaxy assembly and the
buildup of stellar mass in low-metallicity systems. We present the first
VLT/MUSE optical IFU observations of the interacting dwarf pair dm1647+21,
selected from the TiNy Titans survey. The H emission is widespread and
corresponds to a total unobscured star formation rate (SFR) of 0.44 M
yr, 2.7 times higher than the SFR inferred from SDSS data. The implied
specific SFR (sSFR) for the system is elevated by more than an order of
magnitude above non-interacting dwarfs in the same mass range. This increase is
dominated by the lower-mass galaxy, which has a sSFR enhancement of 50.
Examining the spatially-resolved maps of classic optical line diagnostics, we
find the ISM excitation can be fully explained by star formation. The velocity
field of the ionized gas is not consistent with simple rotation. Dynamical
simulations indicate that the irregular velocity field and the stellar
structure is consistent with the identification of this system as an ongoing
interaction between two dwarf galaxies. The widespread, clumpy enhancements in
star formation in this system point to important differences in the effect of
mergers on dwarf galaxies, compared to massive galaxies: rather than the
funneling of gas to the nucleus and giving rise to a nuclear starburst,
starbursts in low-mass galaxy mergers may be triggered by large-scale ISM
compression, and thus be more distributed.Comment: Accepted for publication in ApJ. 11 pages, 5 figures, 1 table.
Figures slightly degraded to meet arXiv size restrictions. For more
information about TiNy Titans see https://lavinia.as.arizona.edu/~tinytitans
Observation of Spin Wave Soliton Fractals in Magnetic Film Active Feedback Rings
The manifestation of fractals in soliton dynamics has been observed for the
first time. The experiment utilized self-generated spin wave envelope solitons
in a magnetic film based active feedback ring. At high ring gain, the soliton
that circulates in the ring breathes in a fractal pattern. The corresponding
power frequency spectrum shows a comb structure, with each peak in the comb
having its own comb, and so on, to finer and finer scales.Comment: 4 pages, 4 figure
Regulatory Taking: A Contract Approach
This Article begins by defining the parameters of the fifth amendment\u27s taking clause. The Article then reviews the various tests used in determining whether governmental action constitutes a taking, and discusses the recent Supreme Court decisions within the framework of case law as it has evolved since the Court\u27s 1922 landmark decision, Pennsylvania Coal Co. v. Mahon. Finally, the Article suggests a formula based on well-established contract principles for analyzing the impact of land use regulation on private property interests
- …