1,368 research outputs found
Perspectives on family health, happiness and harmony (3H) among Hong Kong Chinese people: a qualitative study
Family harmony, an important Confucian ideal in Chinese society is believed to determine family happiness and therefore health, but is this accurate? This is a qualitative study of 41 Hong Kong Chinese family members. Individual recorded interviews were thematically analysed describing perceived interactions between harmony, happiness and health. Family harmony comprised four components: communication, mutual respect, lack of conflict and family time [notably 'Gou tong' (in Cantonese æșé)-opportunity and willingness to spend time together-requiring good interpersonal communication, emphasized by female respondents]. Lack of conflict was emphasized, while diverse values, parenting styles and financial difficulties were common causes of conflict. Respect required reciprocity. Family happiness comprised four elements: family harmony, an important pre-requisite; mutual caring and supportive orientation; sense of security emphasizing financial security in middle-class versus sense of togetherness in lower social class groups and contentment. Healthy families were harmonious; 'typical' (children/two-parent/two-grandparent); happy; caring and respectful, with individual health and healthy behaviours. Family harmony, happiness and health are interrelated and built on a communicative, respectful, caring and contented set of attitudes, in particular allowing for family time. Harmony is apparently a core element of good family functioning.postprin
Quantum-mechanical calculation of Stark widths of Ne VII n=3, transitions
The Stark widths of the Ne VII 2s3s-2s3p singlet and triplet lines are
calculated in the impact approximation using quantum-mechanical Convergent
Close-Coupling and Coulomb-Born-Exchange approximations. It is shown that the
contribution from inelastic collisions to the line widths exceeds the elastic
width contribution by about an order of magnitude. Comparison with the line
widths measured in a hot dense plasma of a gas-liner pinch indicates a
significant difference which may be naturally explained by non-thermal Doppler
effects from persistent implosion velocities or turbulence developed during the
pinch implosion. Contributions to the line width from different partial waves
and types of interactions are discussed as well.Comment: 8 pages, 3 figures; accepted by Phys. Rev.
Differential expression of synaptophysin and synaptoporin during pre- and postnatal development of the hippocampal network
The closely related synaptic vesicle membrane proteins synaptophysin and synaptoporin are abundant in the hippocampal formation of the adult rat. But the prenatal hippocampal formation contains only synaptophysin, which is first detected at embryonic day 17 (E17) in perikarya and axons of the pyramidal neurons. At E21 synaptophysin immunoreactivity extends into the apical dendrites of these cells and in newly formed terminals contacting these dendrites. The transient presence of synaptophysin in axons and dendrites suggests a functional involvement of synaptophysin in fibre outgrowth of developing pyramidal neurons. Synaptoporin expression parallels the formation of dentate granule cell synaptic contacts with pyramidal neurons: the amount of hippocampal synaptoporin, determined in immunoblots and by synaptoporin immunostaining of developing mossy fibre terminals, increases during the first postnatal week. Moreover, in the adult, synaptoporin is found exclusively in the mossy fibre terminals present in the hilar region of the dentate gyrus and the regio inferior of the cornu ammonis. In contrast, synaptophysin is present in all synaptic fields of the hippocampal formation, including the mossy fibre terminals, where it colocalizes with synaptoporin in the same boutons. Our data indicate that granule neuron terminals differ from all other terminals of the hippocampal formation by the presence of both synaptoporin and synaptophysin. This difference, observed in the earliest synaptic contacts in the postnatal hippocampus and persisting into adult life, suggests distinct functions of synaptoporin in these nerve terminals
Thermal conductivity and specific heat of the linear chain cuprate SrCuO: Evidence for thermal transport via spinons
We report measurements of the specific heat and the thermal conductivity of
the model Heisenberg spin-1/2 chain cuprate SrCuO at low
temperatures. In addition to a nearly isotropic phonon heat transport, we find
a quasi one-dimensional excess thermal conductivity along the chain direction,
most likely associated with spin excitations (spinons). The spinon energy
current is limited mainly by scattering on defects and phonons. Analyzing the
specific heat data, the intrachain magnetic exchange is estimated to
be 2650 K.Comment: 4 RevTeX pages, 3 figures, to appear in Phys. Rev.
High-mass star formation at high luminosities: W31 at >10^6 L_sun
Context: High-mass star formation has been a very active field over the last
decade, however, most studies targeted regions of luminosities between 10^4 and
10^5 L_sun. Methods: We selected the W31 star-forming complex with a total
luminosity of ~6x10^6 L_sun for a multi-wavelength spectral line and continuum
study covering wavelengths from the near- and mid-infrared via (sub)mm
wavelength observations to radio data in the cm regime. Results: While the
overall structure of the multi-wavelength continuum data resembles each other
well, there are several intriguing differences. The 24mum emission stemming
largely from small dust grains follows tightly the spatial structure of the cm
emission tracing the ionized free-free emission. Hence warm dust resides in
regions that are spatially associated with the ionized hot gas (~10^4 K) of the
HII regions. Furthermore, we find several evolutionary stages within the same
complexes, ranging from infrared-observable clusters, via deeply embedded
regions associated with active star formation traced by 24\,m and cm
emission, to at least one high-mass gas clump devoid of any such signature. The
13CO(2-1) and C18O(2-1) spectral line observations reveal a large kinematic
breadth in the entire region with a total velocity range of approximately 90
km/s. While the average virial mass ratio for W31 is close to unity, the line
width analysis indicates large-scale evolutionary differences between the
southern and northern sub-regions (G10.2-0.3 and G10.3-0.1) of the whole W31
complex. The clump mass function - tracing cluster scales and not scales of
individual stars - derived from the 875mum continuum data has a slope of
1.5+-0.3, consistent with previous cloud mass functions.Comment: 13 pages, 11 figures, accepted for Astronomy and Astrophysics,
high-resolution version of paper at
http://www.mpia.de/homes/beuther/papers.htm
Outflows from the high-mass protostars NGC 7538 IRS1/2 observed with bispectrum speckle interferometry -- Signatures of flow precession
NGC 7538 IRS1 is a high-mass (approx. 30 M_sun) protostar with a CO outflow,
an associated UCHII region, and a linear methanol maser structure, which might
trace a Keplerian-rotating circumstellar disk. The directions of the various
associated axes are misaligned with each other. We investigate the
near-infrared morphology of the source to clarify the relations among the
various axes. K'-band bispectrum speckle interferometry was performed at two
6-meter-class telescopes -- the BTA 6m telescope and the 6.5m MMT.
Complementary IRAC images from the Spitzer Space Telescope Archive were used to
relate the structures detected with the outflow at larger scales. High-dynamic
range images show fan-shaped outflow structure in which we detect 18 stars and
several blobs of diffuse emission. We interpret the misalignment of various
outflow axes in the context of a disk precession model, including numerical
hydrodynamic simulations of the molecular emission. The precession period is
approx. 280 years and its half-opening angle is 40 degrees. A possible
triggering mechanism is non-coplanar tidal interaction of an (undiscovered)
close companion with the circumbinary protostellar disk. Our observations
resolve the nearby massive protostar NGC 7538 IRS2 as a close binary with
separation of 195 mas. We find indications for shock interaction between the
outflow activities in IRS1 and IRS2. Indications of outflow precession have
been discovered to date in a number of massive protostars, all with large
precession angles 20--45 degrees. This might explain the difference between the
outflow widths in low- and high-mass stars and add support to a common
collimation mechanism.Comment: 20 pages; 8 figures; Accepted by A&A on April 10, 2006; Image quality
reduced due to astro-ph file size limitations; Please download a version with
high-quality images from
http://www.mpifr-bonn.mpg.de/staff/tpreibis/ngc7538.pd
Multidimensional Supernova Simulations with Approximative Neutrino Transport I. Neutron Star Kicks and the Anisotropy of Neutrino-Driven Explosions in Two Spatial Dimensions
By means of two-dimensional (2D) simulations we study hydrodynamic
instabilities during the first seconds of neutrino-driven supernova explosions,
using a PPM hydrodynamics code, supplemented with a gray, non-equilibrium
approximation of radial neutrino transport. We consider three 15 solar mass
progenitors with different structures and one rotating model, in which we
replace the dense core of the newly formed neutron star (NS) by a contracting
inner grid boundary, and trigger neutrino-driven explosions by systematically
varying the neutrino fluxes emitted at this boundary. Confirming more idealized
studies as well as supernova simulations with spectral transport, we find that
random seed perturbations can grow by hydrodynamic instabilities to a globally
asymmetric mass distribution, leading to a dominance of dipole (l=1) and
quadrupole (l=2) modes in the explosion ejecta. Anisotropic gravitational and
hydrodynamic forces are found to accelerate the NS on a timescale of 2-3
seconds. Since the explosion anisotropies develop chaotically, the magnitude of
the corresponding kick varies stochastically in response to small differences
in the fluid flow. Our more than 70 models separate into two groups, one with
high and the other with low NS velocities and accelerations after 1s of
post-bounce evolution, depending on whether the l=1 mode is dominant in the
ejecta or not. This leads to a bimodality of the distribution when the NS
velocities are extrapolated to their terminal values. The fast group has an
average velocity of about 500 km/s and peak values in excess of 1000 km/s.
Establishing a link to the measured distribution of pulsar velocities, however,
requires a much larger set of calculations and ultimately 3D modeling.
(abridged)Comment: 40 pages, 28 figures; significantly shortened and revised version
according to referee's comments; accepted by Astronomy & Astrophysic
Cold atomic gas identified by HI self-absorption. Cold atomic clouds toward giant molecular filaments
Stars form in the dense interiors of molecular clouds. The dynamics and
physical properties of the atomic interstellar medium (ISM) set the conditions
under which molecular clouds and eventually stars will form. It is, therefore,
critical to investigate the relationship between the atomic and molecular gas
phase to understand the global star formation process. Using the high angular
resolution data from The HI/OH/Recombination line survey of the Milky Way
(THOR), we aim to constrain the kinematic and physical properties of the cold
atomic hydrogen gas phase toward the inner Galactic plane. HI self-absorption
(HISA) has proven to be a viable method to detect cold atomic hydrogen clouds
in the Galactic plane. With the help of a newly developed self-absorption
extraction routine (astroSABER), we build upon previous case studies to
identify HI self-absorption toward a sample of Giant Molecular Filaments
(GMFs). We find the cold atomic gas to be spatially correlated with the
molecular gas on a global scale. The column densities of the cold atomic gas
traced by HISA are usually of the order of whereas those
of molecular hydrogen traced by are at least an order of magnitude
higher. The HISA column densities are attributed to a cold gas component that
accounts for a fraction of 5% of the total atomic gas budget within the
clouds. The HISA column density distributions show pronounced log-normal shapes
that are broader than those traced by HI emission. The cold atomic gas is found
to be moderately supersonic with Mach numbers of a few. In contrast,
highly supersonic dynamics drive the molecular gas within most filaments.Comment: 41 pages, 28 figures, accepted for publication in A&
Effectiveness of a mobile smoking cessation service in reaching elderly smokers and predictors of quitting
<p>Abstract</p> <p>Background</p> <p>Different smoking cessation programmes have been developed in the last decade but utilization by the elderly is low. We evaluated a pilot mobile smoking cessation service for the Chinese elderly in Hong Kong and identified predictors of quitting.</p> <p>Methods</p> <p>The Mobile Smoking Cessation Programme (MSCP) targeted elderly smokers (aged 60 or above) and provided service in a place that was convenient to the elderly. Trained counsellors provided individual counselling and 4 week's free supply of nicotine replacement therapy (NRT). Follow up was arranged at 1 month by face-to-face and at 3 and 6 months by telephone plus urinary cotinine validation. A structured record sheet was used for data collection. The service was evaluated in terms of process, outcome and cost.</p> <p>Results</p> <p>102 governmental and non-governmental social service units and private residential homes for the elderly participated in the MSCP. We held 90 health talks with 3266 elderly (1140 smokers and 2126 non-smokers) attended. Of the 1140 smokers, 365 (32%) received intensive smoking cessation service. By intention-to-treat, the validated 7 day point prevalence quit rate was 20.3% (95% confidence interval: 16.2%â24.8%). Smoking less than 11 cigarettes per day and being adherent to NRT for 4 weeks or more were significant predictors of quitting. The average cost per contact was US168; per self-reported quitter: US827.</p> <p>Conclusion</p> <p>This mobile smoking cessation programme was acceptable to elderly Chinese smokers, with quit rate comparable to other comprehensive programmes in the West. A mobile clinic is a promising model to reach the elderly and probably other hard to reach smokers.</p
Inner Rim of A Molecular Disk Spatially Resolved in Infrared CO Emission Lines
We present high-resolution infrared spectroscopy of the Herbig Ae star HD
141569 A in the CO v=2-1 transition. With the angular resolution attained by
the adaptive optics system, the gas disk around HD 141569 A is spatially
resolved down to its inner-rim truncation. The size of the inner clearing is
11+-2 AU in radius, close to the gravitational radius of the star. The rough
coincidence to the gravitational radius indicates that the viscous accretion
working together with the photoevaporation by the stellar radiation has cleared
the inner part of the disk.Comment: 6 pages, 3 figures, Accepted for publication in the Astrophysical
Journa
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