1,747 research outputs found
Bjerrum pairing correlations at charged interfaces
Electrostatic correlations play a fundamental role in aqueous solutions. In
this letter, we identify transverse and lateral correlations as two mutually
exclusive regimes. We show that the transverse regime leads to binding by
generalization of Bjerrum pair formation theory, yielding binding constants
from first-principle statistical-mechanical calculations. We compare our
theoretical predictions with experiments on charged membranes and Langmuir
monolayers and find good agreement. We contrast our approach with existing
theories in the strong-coupling limit and on charged modulated interfaces, and
discuss different scenarios that lead to charge reversal and equal-sign
attraction by macro-ions.Comment: 7 pages, 4 figure
Building the Galactic halo from globular clusters: evidence from chemically unusual red giants
We present a spectroscopic search for halo field stars that originally formed
in globular clusters. Using moderate-resolution SDSS-III/SEGUE-2 spectra of 561
red giants with typical halo metallicities (-1.8 < [Fe/H] < -1.0), we identify
16 stars, 3% of the sample, with CN and CH bandstrength behavior indicating
depleted carbon and enhanced nitrogen abundances relative to the rest of the
data set. Since globular clusters are the only environment known in which stars
form with this pattern of atypical light-element abundances, we claim that
these stars are second-generation globular cluster stars that have been lost to
the halo field via normal cluster mass-loss processes. Extrapolating from
theoretical models of two-generation globular cluster formation, this result
suggests that globular clusters contributed significant numbers of stars to the
construction of the Galactic halo: we calculate that a minimum of 17% of the
present-day mass of the stellar halo was originally formed in globular
clusters. The ratio of CN-strong to CN-normal stars drops with Galactocentric
distance, suggesting that the inner-halo population may be the primary
repository of these stars.Comment: 9 pages including 8 figures, A&A accepte
From the Field | Field Notes From Jail: How Incarceration and Homelessness Impact Women’s Health
A multi-disciplinary team explored the journey they took with female inmates to develop a collaborative research strategy among the university, community organizations, and the correctional facility. The team consisted of academic researchers, inner city physicians, social workers, nurses, Aboriginal art therapists, Aboriginal cultural consultants, correctional healthcare administrators, and inner city chaplains from non-profit organizations. This paper describes how the team reflected on the journey to determine the impact of incarceration and/or homelessness on the health of female inmates, as they (the team) patiently waited for ethics boards and administrative approval; negotiated correctional center lockdowns; and became exhausted from trying to reconnect with women who were released from incarceration. The researchers discovered what kept them passionate about helping female inmates work through multiple hurdles that included housing, child custody, employment, probation appointments, and counseling. These administrative and operational challenges strengthened the team’s resolve to support these vulnerable women
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Brief behavioural activation for adolescent depression: working with complexity and risk
Given the long-term negative outcomes associated with depression in adolescence, there is a pressing need to develop brief, evidence based treatments that are accessible to more young people experiencing low mood. Behavioural Activation (BA) is an effective treatment for adult depression, however little research has focused on the use of BA with depressed adolescents, particularly with briefer forms of BA. In this article we outline an adaptation of brief Behavioral Activation Treatment of Depression (BATD) designed for adolescents and delivered in eight sessions (Brief BA). This case example illustrates how a structured, brief intervention was useful for a depressed young person with a number of complicating and risk factors
Weighted norm inequalities, off-diagonal estimates and elliptic operators. Part IV: Riesz transforms on manifolds and weights
This is the fourth article of our series. Here, we study weighted norm
inequalities for the Riesz transform of the Laplace-Beltrami operator on
Riemannian manifolds and of subelliptic sum of squares on Lie groups, under the
doubling volume property and Gaussian upper bounds.Comment: 12 pages. Fourth of 4 papers. Important revision: improvement of main
result by eliminating use of Poincar\'e inequalities replaced by the weaker
Gaussian keat kernel bound
Properties of the Meson at Finite Temperature and Density
The mass shift, width broadening, and spectral density for the meson
in a heat bath of nucleons and pions is calculated using a general formula
which relates the self-energy to the forward scattering amplitude. We use
experimental data to saturate the scattering amplitude at low energies with
resonances and include a background Pomeron term, while at high energies a
Regge parameterization is used. The peak of the spectral density is little
shifted from its vacuum position, but the width is considerably increased due
to collisional broadening. At normal nuclear matter density and a temperature
of 150 MeV the spectral density of the meson has a width of 140 MeV.
Zero temperature nuclear matter is also discussed.Comment: 5 pages revtex4, 3 figur
hVH-5: A Protein Tyrosine Phosphatase Abundant in Brain that Inactivates Mitogen-Activated Protein Kinase
A novel protein tyrosine phosphatase [ h omologue of v accinia virus H 1 phosphatase gene clone 5 (hVH-5)] was cloned; it shared sequence similarity with a subset of protein tyrosine phosphatases that regulate mitogen-activated protein kinase. The catalytic region of hVH-5 was expressed as a fusion protein and was shown to hydrolyze p -nitrophenylphosphate and inactivate mitogen-activated protein kinase, thus proving that hVH-5 possessed phosphatase activity. A unique proline-rich region distinguished hVH-5 from other closely related protein tyrosine phosphatases. Another feature that distinguished hVH-5 from related phosphatases was that hVH-5 was expressed predominantly in the adult brain, heart, and skeletal muscle. In addition, in situ hybridization histochemistry of mouse embryo revealed high levels of expression and a wide distribution in the central and peripheral nervous system. Some specific areas of abundant hVH-5 expression included the olfactory bulb, retina, layers of the cerebral cortex, and cranial and spinal ganglia. hVH-5 was induced in PC12 cells upon nerve growth factor and insulin treatment in a manner characteristic of an immediate-early gene, suggesting a possible role in the signal transduction cascade.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65883/1/j.1471-4159.1995.65041823.x.pd
‘It stays with you’: multiple evocative representations of dance and future possibilities for studies in sport and physical cultures
This article considers the integration of arts-based representations via poetic narratives together with artistic representation on dancing embodiment so as to continue an engagement with debates regarding multiple forms/representations. Like poetry, visual images are unique and can evoke particular kinds of emotional and visceral responses, meaning that alternative representational forms can resonate in different and powerful ways. In the article, we draw on grandparent-grandchild interactions, narrative poetry, and artistic representations of dance in order to illustrate how arts-based methods might synergise to offer new ways of ‘knowing’ and ‘seeing’. The expansion of the visual arts into interdisciplinary methodological innovations is a relatively new, and sometimes contentious approach, in studies of sport and exercise. We raise concerns regarding the future for more arts-based research in the light of an ever-changing landscape of a neoliberal university culture that demands high productivity in reductionist terms of what counts as ‘output’, often within very restricted time-frames. Heeding feminist calls for ‘slow academies’ that attempt to ‘change’ time collectively, and challenge the demands of a fast-paced audit culture, we consider why it is worth enabling creative and arts-based methods to continue to develop and flourish in studies of sport, exercise and health, despite the mounting pressures to ‘perform’
A Survey of CN and CH Variations in Galactic Globular Clusters from SDSS Spectroscopy
We present a homogeneous survey of the CN and CH bandstrengths in eight
Galactic globular clusters observed during the course of the Sloan Extension
for Galactic Understanding and Exploration (SEGUE) sub-survey of the SDSS. We
confirm the existence of a bimodal CN distribution among RGB stars in all of
the clusters with metallicity greater than [Fe/H] = -1.7; the lowest
metallicity cluster with an observed CN bimodality is M53, with [Fe/H] ~ -2.1.
There is also some evidence for individual CN groups on the subgiant branches
of M92, M2, and M13, and on the red giant branches of M92 and NGC 5053.
Finally, we quantify the correlation between overall cluster metallicity and
the slope of the CN bandstrength-luminosity plot as a means of further
demonstrating the level of CN-enrichment in cluster giants. Our results agree
well with previous studies reported in the literature.Comment: AJ submitted; 80 pages, 22 figure
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