3,758 research outputs found
Notes from the youth mental health field: Using movement towards goals as a potential indicator of service change and quality improvement
The aim of this paper is to report our notes from the field on using movement toward goals at an aggregate level as an inference of service effectiveness. Analysis of routinely collected data from UK youth mental health services was conducted (N = 8,172, age M = 13.8, 67% female, 32% male) to explore the impact of including goal-based outcome data in combined calculations of standardized measures based on the principles of reliable change (“measurable change”). Due to the broad nature of standardized measures, inferred validity becomes diluted in any team or service level aggregate analysis. To make inferences that are closer to the person's interpretation of their difficulties, we argue that Idiographic Patient Reported Outcome Measures (I-PROMs) counterbalance these limitations. This is supported by our findings. The measurable change metric is the first step towards enabling national analysis of aggregated I-PROMs. I-PROMs, supplemented by standardized measures should be used to consider service evaluation
Equilibrium and stability properties of a coupled two-component Bose-Einstein condensate
The equilibrium and stability properties of a coupled two-component BEC is
studied using a variational method and the one-dimensional model of Williams
and collaborators. The variational parameters are the population fraction,
translation and scaling transformation of the condensate densities, assumed to
have a Gaussian shape. We study the equilibrium and stability properties as a
function of the strength of the laser field and the traps displacement. We find
many branches of equilibrium configurations, with a host of critical points. In
all cases, the signature of the onset of criticality is the collapse of a
normal mode which is a linear combination of the out of phase translation and
an in phase breathing oscillation of the condensate densities. Our calculations
also indicate that we have symmetry breaking effects when the traps are not
displacedComment: 13 pages,3 figure
CD4 cell responses to combination antiretroviral therapy in patients starting therapy at high CD4 cell counts
Objective: To examine CD4 cell responses to combination antiretroviral therapy (cART) in patients enrolled in the Australian HIV Observational Database who commenced cART at CD4 cell counts >350 cells per microliter. Methods: CD4 cell counts were modelled using random effects, repeated measurement models in 432 HIV-infected adults from Australian HIV Observational Database who commenced their first cART regimen and had a baseline CD4 count >350 cells per microliter. Using published AIDS and/or death incidence rates combined with the data summarized by time and predicted CD4 cell count, we calculated the expected reduction in risk of an event for different starting baseline CD4 strata. Results: Mean CD4 counts increased above 500 cells per microliter in all baseline CD4 strata by 12 months (means of 596, 717, and 881 cells/μL in baseline CD4 strata 351-500, 501-650, and >650 cells/μL, respectively) and after 72 months since initiating cART, mean CD4 cell counts (by increasing baseline CD4 strata) were 689, 746, 742 cells per microliter. The expected reduction in risk of mortality for baseline CD4 counts >650 cells per microliter relative to 351-500 cells per microliter was approximately 8%, an absolute risk reduction 0.33 per 1000 treated patient-years. Conclusions: Patients starting cART at high CD4 cell counts (>650 cells/μL) tend to maintain this immunological level over 6 years of follow-up. Patients starting from 351 to 500 CD4 cells per microliter achieve levels of >650 cells per microliter after approximately 3 years of cART. Initiating cART with a baseline CD4 count 501-650 or >650 cells per microliter relative to 351-500 cells per microliter indicated a minimal reduction in risk of AIDS incidence and/or death. Copyright © 2011 Lippincott Williams & Wilkins
Breaking the Smallsat Barriers to Sub-50cm Imaging
New cutting-edge imaging sensors can now reduce instrument size and mass, leading to mission cost savings, and bring sub-50cm imaging capability into the realm of small satellites. Whilst aperture is essential to achieving resolution, half-pixel shifted sensor architectures decouple achievable Ground Sampling Distance (GSD) from the native ground projected pixel. This facilitates the deployment of Very High Resolution (VHR) small satellite constellations featuring improved Signal-to-Noise performance and increased area collection rates compared to push-frame systems.
A fundamental limitation to the theoretical performance of an optical system is imposed by its aperture diameter; hence, for a given aperture, the aim is to maximize the information content resolved up to this limit. This is achieved by minimizing losses caused by aberrations in the optical system and enhancing platform stability on-orbit. Further information is lost due to aliasing at higher spatial frequencies; however, the recovery of such information is unlocked through the novel sensor technology and processing techniques proposed.
Funded under the European Space Agency (ESA) “Investing in Industrial Innovation” (InCubed) program, this paper reports on the build and verification campaign of a sub-50cm capable instrument Proto-Flight Model (PFM), the beneficial properties of half-pixel offset sensors, and the platform supporting such a payload
Constraints on intragroup stellar mass from hostless Type Ia supernova
We probe the diffuse stellar mass in a sample of 1401 low redshift galaxy
groups (10E13 - 10E14 Msun/h) by examining the rate of hostless Type Ia
supernova (SNe Ia) within the groups. We correlate the sample of confirmed SNe
Ia from the SDSS supernova survey with the positions of our galaxy groups, as
well as with the resolved galaxies within them. We find that 19 of the 59 SNe
Ia within the group sample have no detectable host galaxy, with another three
ambiguous instances. This gives a robust upper limit that a maximum of 2.69%
+1.58%/-1.34% of the group's total mass arises from diffuse stars in the
intragroup medium. After correcting for a contribution from "prompt" SNe
occurring within galaxies, and including a contribution from those which arise
in dwarf galaxies below our photometric limit, we find that only 1.32%
+0.78%/-0.70% of the group's total mass is likely in the form of diffuse
stellar mass. Combining this result with the galaxy stellar mass functions of
Yang et al., we find that 47% +16%/-15% of the stellar mass in our groups is in
the form of diffuse light, so that stars make up a fraction 0.028 +0.011/-0.010
of the total group mass. Galaxy groups appear to be very efficient in
disrupting stellar mass into a diffuse component; however, stars still make up
a small fraction of the group mass, comparable to that seen in rich clusters.
This remains a challenge to galaxy formation models.Comment: 5 pages, MNRAS Letters, in pres
A Comparative Study of the Formation of Aromatics in Rich Methane Flames Doped by Unsaturated Compounds
For a better modeling of the importance of the different channels leading to
the first aromatic ring, we have compared the structures of laminar rich
premixed methane flames doped with several unsaturated hydrocarbons: allene and
propyne, because they are precursors of propargyl radicals which are well known
as having an important role in forming benzene, 1,3-butadiene to put in
evidence a possible production of benzene due to reactions of C4 compounds,
and, finally, cyclopentene which is a source of cyclopentadienylmethylene
radicals which in turn are expected to easily isomerizes to give benzene. These
flames have been stabilized on a burner at a pressure of 6.7 kPa (50 Torr)
using argon as dilutant, for equivalence ratios (?) from 1.55 to 1.79. A unique
mechanism, including the formation and decomposition of benzene and toluene,
has been used to model the oxidation of allene, propyne, 1,3 butadiene and
cyclopentene. The main reaction pathways of aromatics formation have been
derived from reaction rate and sensitivity analyses and have been compared for
the three types of additives. These combined analyses and comparisons can only
been performed when a unique mechanism is available for all the studied
additives
Synthesis of compact wind profiles using evolutionary algorithms
In this paper, the authors face the problem of wind speed processing as environmental variable of a wind turbine system. Generally, the information on wind speed measurements is processed over long periods of time to be relevant with respect to the site characteristics (average and maximum speeds, statistics). Subsequent large scale profiles of wind speed lead to long processing time for simulation analysis and especially for optimization design that penalizes the search of optimal solutions. An original synthesis approach of a compact and representative wind speed profile using an Evolutionary Algorithm (EA) is proposed. This approach is compared to a purely statistical approach based on random number generators. It allows reducing the actual wind profile duration with compression ratios greater (two months of wind speed measurements are compressed in only 1 hour). Then, the synthesis approach by EA is applied to the sizing of an autonomous hybrid system based on wind turbine with battery storage for stand-alone energy systems. It has proven its effectiveness in reducing 200 days of wind speed measurements in only 10 days, allowing sizing the storage system with a significant gain in terms of computing time in the framework of the optimization process
The Chemistry of the Trailing arm of the Sagittarius Dwarf Galaxy
We present abundances of C, O, Ti, and Fe for eleven M-giant stars in the
trailing tidal arm of the Sagittarius dwarf (Sgr). The abundances were derived
by comparing synthetic spectra with high-resolution infrared spectra obtained
with the Phoenix spectrograph on the Gemini South telescope. The targeted stars
are drawn from two regions of the Sgr trailing arm separated by 66 degrees (5
stars) and 132 degrees (6 stars) from the main body of Sgr. The trailing arm
provides a more direct diagnostic of the chemical evolution of Sgr compared to
the extensively phase-mixed leading arm.
Within our restricted sample of ~2-3 Gyr old stars, we find that the stream
material exhibits a significant metallicity gradient of -(2.4\pm0.3)x10^{-3}
dex / degree (-(9.4\pm1.1)x10^{-4} dex / kpc) away from the main body of Sgr.
The tidal disruption of Sgr is a relatively recently event. We therefore
interpret the presence of a metallicity gradient in the debris as indicative of
a similar gradient in the progenitor. The fact that such a metallicity gradient
survived for almost a Hubble time indicates that the efficiency of radial
mixing was very low in the Sgr progenitor.
No significant gradient is seen to exist in the [alpha/Fe] abundance ratio
along the trailing arm. Our results may be accounted for by a radial decrease
in star formation efficiency and/or radial increase in the efficiency of
galactic wind-driven metal loss in the chemical evolution of the Sgr
progenitor. The [Ti/Fe] and [O/Fe] abundance ratios observed within the stream
are distinct from those of the Galactic halo. We conclude that the fraction of
the intermediate to metal-rich halo population contributed by the recent
dissolution (<3 Gyr) of Sgr-like dwarf galaxies can not be substantial.Comment: 22 pages, 7 figures, ApJ accepte
The first 62 AGN observed with SDSS-IV MaNGA -- III: stellar and gas kinematics
We investigate the effects of Active Galactic Nuclei (AGN) on the gas
kinematics of their host galaxies, using MaNGA data for a sample of 62 AGN
hosts and 109 control galaxies (inactive galaxies). We compare orientation of
the line of nodes (kinematic Position Angle - PA) measured from the gas and
stellar velocity fields for the two samples. We found that AGN hosts and
control galaxies display similar kinematic PA offsets between gas and stars.
However, we note that AGN have larger fractional velocity dispersion
differences between gas and stars [] when compared to their controls, as
obtained from the velocity dispersion values of the central (nuclear) pixel
(2.5" diameter). The AGN have a median value of of
, while the the median value for the control
galaxies is . 75% of the AGN show
, while 75% of the normal galaxies show , thus we suggest that the parameter can be
used as an indicative of AGN activity. We find a correlation between the
[OIII]5007 luminosity and for our sample. Our main
conclusion is that the AGN already observed with MaNGA are not powerful enough
to produce important outflows at galactic scales, but at 1-2 kpc scales, AGN
feedback signatures are always present on their host galaxies.Comment: 19 pages, 8 figures, published in MNRA
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