237 research outputs found
MCG+00-32-16: An Irregular Galaxy Close to the Lowest Redshift Absorber on the 3C 273 Line of Sight
MCG+00-32-16 is the galaxy closest in position-velocity space to the lowest
redshift Ly absorber along the line-of-sight to the quasar 3C 273. Its
projected separation is 204 (d/19 Mpc) kpc, where d is the distance from the
Milky Way to the galaxy, and the redshift difference is only 94 km/s; HI
1225+01 is slightly closer in projected separation to the absorber, but has a
greater redshift difference. We present HI synthesis array mapping and CCD
photometry in B and R for MCG+00-32-16. The HI disk is rotating in such a way
that the side of the galaxy closer to the sight-line to the quasar has the
larger velocity difference from the absorber. The absorber may be a ``failed
dwarf'' member of a poor galaxy group of which MCG+00-32-16 and HI 1225+01 are
the only members to have formed stars.Comment: 14 pages, 9 figures, accepted by Astrophysical Journa
Cosmological SPH simulations with four million particles: statistical properties of X-ray clusters in a low-density universe
We present results from a series of cosmological SPH (smoothed particle
hydrodynamics) simulations coupled with the P3M
(Particle-Particle-Particle-Mesh) solver for the gravitational force. The
simulations are designed to predict the statistical properties of X-ray
clusters of galaxies as well as to study the formation of galaxies. We have
seven simulation runs with different assumptions on the thermal state of the
intracluster gas. Following the recent work by Pearce et al., we modify our SPH
algorithm so as to phenomenologically incorporate the galaxy formation by
decoupling the cooled gas particles from the hot gas particles. All the
simulations employ 128^3 particles both for dark matter and for gas components,
and thus constitute the largest systematic catalogues of simulated clusters in
the SPH method performed so far. These enable us to compare the analytical
predictions on statistical properties of X-ray clusters against our direct
simulation results in an unbiased manner. We find that the luminosities of the
simulated clusters are quite sensitive to the thermal history and also to the
numerical resolution of the simulations, and thus are not reliable. On the
other hand, the mass-temperature relation for the simulated clusters is fairly
insensitive to the assumptions of the thermal state of the intracluster gas,
robust against the numerical resolution, and in fact agrees well with the
analytic prediction. Therefore the prediction for the X-ray temperature
function of clusters on the basis of the Press-Schechter mass function and the
virial equilibrium is fairly reliable.Comment: Accepted for publication in The Astrophysical Journal. 18 pages with
7 embedded figure
Evaluating case studies of community-oriented integrated care.
This paper summarises a ten-year conversation within London Journal of Primary Care about the nature of community-oriented integrated care (COIC) and how to develop and evaluate it. COIC means integration of efforts for combined disease-treatment and health-enhancement at local, community level. COIC is similar to the World Health Organisation concept of a Community-Based Coordinating Hub - both require a local geographic area where different organisations align their activities for whole system integration and develop local communities for health. COIC is a necessary part of an integrated system for health and care because it enables multiple insights into 'wicked problems', and multiple services to integrate their activities for people with complex conditions, at the same time helping everyone to collaborate for the health of the local population. The conversation concludes seven aspects of COIC that warrant further attention
Health outcomes of online consumer health information: A systematic mixed studies review with framework synthesis.
The Internet has become the first source of consumer health information. Most theoretical and empirical studies are centered on information needs and seeking, rather than on information outcomes. This review's purpose is to explore and explain health outcomes of Online Consumer Health Information (OCHI) in primary care. A participatory systematic mixed studies review with a framework synthesis was undertaken. Starting from an initial conceptual framework, our specific objectives were to (a) identify types of OCHI outcomes in primary care, (b) identify factors associated with these outcomes, and (c) integrate these factors and outcomes into a comprehensive revised framework combining an information theory and a psychosocial theory of behavior. The results of 65 included studies were synthesized using a qualitative thematic data analysis. The themes derived from the literature underwent a harmonization process that produced a comprehensive typology of OCHI outcomes. The revised conceptual framework specifies four individual and one organizational level of OCHI outcomes, while including factors such as consumers' information needs and four interdependent contextual factors. It contributes to theoretical knowledge about OCHI health outcomes, and informs future research, information assessment methods, and tools to help consumers find and use health information
Neural Response After a Single ECT Session During Retrieval of Emotional Self-Referent Words in Depression:A Randomized, Sham-Controlled fMRI Study
Formation of Sub-galactic Clouds under UV Background Radiation
The effects of the UV background radiation on the formation of sub-galactic
clouds are studied by means of one-dimensional hydrodynamical simulations. The
radiative transfer of the ionizing photons due to the absorption by HI, HeI and
HeII, neglecting the emission, is explicitly taken into account. We find that
the complete suppression of collapse occurs for the clouds with circular
velocities typically in the range V_c \sim 15-40 km/s and the 50% reduction in
the cooled gas mass with V_c \sim 20-55 km/s. These values depend most
sensitively on the collapse epoch of the cloud, the shape of the UV spectrum,
and the evolution of the UV intensity. Compared to the optically thin case,
previously investigated by Thoul & Weinberg (1996), the absorption of the
external UV photon by the intervening medium systematically lowers the above
threshold values by \Delta V_c \sim 5 km/s. Whether the gas can contract or
keeps expanding is roughly determined by the balance between the gravitational
force and the thermal pressure gradient when it is maximally exposed to the
external UV flux. Based on our simulation results, we discuss a number of
implications on galaxy formation, cosmic star formation history, and the
observations of quasar absorption lines. In Appendix, we derive analytical
formulae for the photoionization coefficients and heating rates, which
incorporate the frequency/direction-dependent transfer of external photons.Comment: 38 pages, 16 figures, accepted for publication in Ap
Formation of Disk Galaxies: Warm Dark Matter and the Angular Momentum problem
We have performed TreeSPH simulations of disk galaxy formation in various
warm dark matter (WDM) cosmologies. Our results indicate that for a range of
WDM free-streaming masses, the disk galaxy formation angular momentum problem
can be completely resolved by going to the WDM structure formation scenario,
without having to invoke stellar feedback processes at all. We also confirm our
previous suspicion, that part of the angular momentum problem is due to
numerical effects, most likely related to the shock capturing, artificial
viscosity used in SPH. Furthermore we find that we can match the observed
I-band Tully-Fisher (TF) relation, provided that the I-band mass-to-light ratio
of disk galaxies is about 0.8. We argue that this is quite a reasonable value
in comparison with various dynamical and spectrophotometric estimates,
including one given in this paper. We speculate that our success in matching
the TF relation may be due to WDM halos being less centrally concentrated than
CDM halos and suggest to check this exciting possibility with high resolution
simulations, in particular in low Omega_M, WDM cosmologies. Finally, we discuss
possible physical candidates for WDM particles extensively. We find that the
most promising are neutrinos with weaker or stronger interactions than normal,
majorons (light pseudogoldstone bosons) or mirror or shadow world neutrinos.Comment: 50 pages incl. 17 figures. Accepted for publication in Ap
Magnetic Field and Pressure Phase Diagrams of Uranium Heavy-Fermion Compound UZn
We have performed magnetization measurements at high magnetic fields of up to
53 T on single crystals of a uranium heavy-fermion compound UZn
grown by the Bridgman method. In the antiferromagnetic state below the N\'{e}el
temperature = 9.7 K, a metamagnetic transition is found at
32 T for the field along the [110] direction (-axis). The
magnetic phase diagram for the field along the [110] direction is
given. The magnetization curve shows a nonlinear increase at 35
T in the paramagnetic state above up to a characteristic
temperature where the magnetic susceptibility or
electrical resistivity shows a maximum value. This metamagnetic behavior of the
magnetization at is discussed in comparison with the metamagnetic
magnetism of the heavy-fermion superconductors UPt, URuSi, and
UPdAl. We have also carried out high-pressure resistivity measurement
on UZn using a diamond anvil cell up to 8.7 GPa. Noble gas argon was
used as a pressure-transmitting medium to ensure a good hydrostatic
environment. The N\'{e}el temperature is almost
pressure-independent up to 4.7 GPa and starts to increase in the
higher-pressure region. The pressure dependences of the coefficient of the
term in the electrical resistivity , the antiferromagnetic gap
, and the characteristic temperature are
discussed. It is found that the effect of pressure on the electronic states in
UZn is weak compared with those in the other heavy fermion
compounds
Lithium induced hypercalcemia:an expert opinion and management algorithm
Background: Lithium is the gold standard prophylactic treatment for bipolar disorder. Most clinical practice guidelines recommend regular calcium assessments as part of monitoring lithium treatment, but easy-to-implement specific management strategies in the event of abnormal calcium levels are lacking. Methods: Based on a narrative review of the effects of lithium on calcium and parathyroid hormone (PTH) homeostasis and its clinical implications, experts developed a step-by-step algorithm to guide the initial management of emergent hypercalcemia during lithium treatment. Results: In the event of albumin-corrected plasma calcium levels above the upper limit, PTH and calcium levels should be measured after two weeks. Measurement of PTH and calcium levels should preferably be repeated after one month in case of normal or high PTH level, and after one week in case of low PTH level, independently of calcium levels. Calcium levels above 2.8 mmol/l may require a more acute approach. If PTH and calcium levels are normalized, repeated measurements are suggested after six months. In case of persistent PTH and calcium abnormalities, referral to an endocrinologist is suggested since further examination may be needed. Conclusions: Standardized consensus driven management may diminish the potential risk of clinicians avoiding the use of lithium because of uncertainties about managing side-effects and consequently hindering some patients from receiving an optimal treatment
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