151 research outputs found
Employment in Personality Disorders and the Effectiveness of Individual Placement and Support:Outcomes from a Secondary Data Analysis
Purpose Personality disorders (PDs) are associated with severe functional impairment and subsequent high societal costs, increasing the need to improve occupational functioning in PD. Individual placement and support (IPS) is an effective, evidence-based method of supported employment, which so far has been tested in various mixed patient populations with severe mental illness (SMI, including PDs). However, the effectiveness of IPS for PDs per se remains uninvestigated. Methods Data from the SCION trial were used, including 31 SMI patients with PDs and 115 SMI patients with other primary diagnoses (primarily psychotic disorders). First, the interaction effect of diagnosis (PD vs other SMI) and intervention (IPS vs traditional vocational rehabilitation) was studied. Second, in the IPS condition, difference between diagnostic groups in time to first job was studied. Results We did not find evidence of a moderating effect of PD diagnosis on the primary effect of IPS (proportion who started in regular employment) (OR = 0.592, 95% CI 0.80–4.350, p = 0.606) after 30 months. Also, PD diagnosis did not moderate the effect of time until first job in IPS. Conclusions From the present explorative analysis we did not find evidence for a moderating effect of PD diagnosis on the effectiveness of IPS among PD participants. This indicates that IPS could be as effective in gaining employment in participants with PD as it is in participants with other SMI. Future studies, implementing larger numbers, should confirm whether IPS is equally effective in PDs and study whether augmentations or alterations to the standard IPS model might be beneficiary for PD
The enigmatic nature of the circumstellar envelope and bow shock surrounding Betelgeuse as revealed by Herschel. I. Evidence of clumps, multiple arcs, and a linear bar-like structure
Context. The interaction between stellar winds and the interstellar medium
(ISM) can create complex bow shocks. The photometers on board the Herschel
Space Observatory are ideally suited to studying the morphologies of these bow
shocks. Aims. We aim to study the circumstellar environment and wind-ISM
interaction of the nearest red supergiant, Betelgeuse. Methods. Herschel PACS
images at 70, 100, and 160 micron and SPIRE images at 250, 350, and 500 micron
were obtained by scanning the region around Betelgeuse. These data were
complemented with ultraviolet GALEX data, near-infrared WISE data, and radio 21
cm GALFA-HI data. The observational properties of the bow shock structure were
deduced from the data and compared with hydrodynamical simulations. Results.
The infrared Herschel images of the environment around Betelgeuse are
spectacular, showing the occurrence of multiple arcs at 6-7 arcmin from the
central target and the presence of a linear bar at 9 arcmin. Remarkably, no
large-scale instabilities are seen in the outer arcs and linear bar. The dust
temperature in the outer arcs varies between 40 and 140 K, with the linear bar
having the same colour temperature as the arcs. The inner envelope shows clear
evidence of a non-homogeneous clumpy structure (beyond 15 arcsec), probably
related to the giant convection cells of the outer atmosphere. The
non-homogeneous distribution of the material even persists until the collision
with the ISM. A strong variation in brightness of the inner clumps at a radius
of 2 arcmin suggests a drastic change in mean gas and dust density some 32 000
yr ago. Using hydrodynamical simulations, we try to explain the observed
morphology of the bow shock around Betelgeuse. Conclusions: [abbreviated]Comment: 26 page
First Stars. II. Evolution with mass loss
The first stars are assumed to be predominantly massive. Although, due to the
low initial abundances of heavy elements the line-driven stellar winds are
supposed to be inefficient in the first stars, these stars may loose a
significant amount of their initial mass by other mechanisms.
In this work, we study the evolution with a prescribed mass loss rate of very
massive, galactic and pregalactic, Population III stars, with initial
metallicities and , respectively, and initial masses
100, 120, 150, 200, and 250 during the hydrogen and helium burning
phases.
The evolution of these stars depends on their initial mass, metallicity and
the mass loss rate. Low metallicity stars are hotter, compact and luminous, and
they are shifted to the blue upper part in the Hertzprung-Russell diagram. With
mass loss these stars provide an efficient mixing of nucleosynthetic products,
and depending on the He-core mass their final fate could be either
pair-instability supernovae or energetic hypernovae. These stars contributed to
the reionization of the universe and its enrichment with heavy elements, which
influences the subsequent star formation properties.Comment: Accepted for publication in Astrophysics & Space Science. 15 pages,
18 figure
Mass-loss rates of Very Massive Stars
We discuss the basic physics of hot-star winds and we provide mass-loss rates
for (very) massive stars. Whilst the emphasis is on theoretical concepts and
line-force modelling, we also discuss the current state of observations and
empirical modelling, and address the issue of wind clumping.Comment: 36 pages, 15 figures, Book Chapter in "Very Massive Stars in the
Local Universe", Springer, Ed. Jorick S. Vin
Instabilities in the Envelopes and Winds of Very Massive Stars
The high luminosity of Very Massive Stars (VMS) means that radiative forces
play an important, dynamical role both in the structure and stability of their
stellar envelope, and in driving strong stellar-wind mass loss. Focusing on the
interplay of radiative flux and opacity, with emphasis on key distinctions
between continuum vs. line opacity, this chapter reviews instabilities in the
envelopes and winds of VMS. Specifically, we discuss how: 1) the iron opacity
bump can induce an extensive inflation of the stellar envelope; 2) the density
dependence of mean opacity leads to strange mode instabilities in the outer
envelope; 3) desaturation of line-opacity by acceleration of near-surface
layers initiates and sustains a line-driven stellar wind outflow; 4) an
associated line-deshadowing instability leads to extensive small-scale
structure in the outer regions of such line-driven winds; 5) a star with
super-Eddington luminosity can develop extensive atmospheric structure from
photon bubble instabilities, or from stagnation of flow that exceeds the
"photon tiring" limit; 6) the associated porosity leads to a reduction in
opacity that can regulate the extreme mass loss of such continuum-driven winds.
Two overall themes are the potential links of such instabilities to Luminous
Blue Variable (LBV) stars, and the potential role of radiation forces in
establishing the upper mass limit of VMS.Comment: 44 pages, 13 figures. Chapter to appear in the book "Very Massive
Stars in the Local Universe", Springer, J.S. Vink, e
Mammography screening: views from women and primary care physicians in Crete
Background: Breast cancer is the most commonly diagnosed cancer among women and a leading cause of death from cancer in women in Europe. Although breast cancer incidence is on the rise worldwide, breast cancer mortality over the past 25 years has been stable or decreasing in some countries and a fall in breast cancer mortality rates in most European countries in the 1990s was reported by several studies, in contrast, in Greece have not reported these favourable trends. In Greece, the age-standardised incidence and mortality rate for breast cancer per 100.000 in 2006 was 81,8 and 21,7 and although it is lower than most other countries in Europe, the fall in breast cancer mortality that observed has not been as great as in other European countries. There is no national strategy for screening in this country. This study reports on the use of mammography among middleaged women in rural Crete and investigates barriers to mammography screening encountered by women and their primary care physicians.
Methods: Design: Semi-structured individual interviews. Setting and participants: Thirty women between 45–65
years of age, with a mean age of 54,6 years, and standard deviation 6,8 from rural areas of Crete and 28 qualified
primary care physicians, with a mean age of 44,7 years and standard deviation 7,0 serving this rural population.
Main outcome measure: Qualitative thematic analysis.
Results: Most women identified several reasons for not using mammography. These included poor knowledge
of the benefits and indications for mammography screening, fear of pain during the procedure, fear of a serious
diagnosis, embarrassment, stress while anticipating the results, cost and lack of physician recommendation.
Physicians identified difficulties in scheduling an appointment as one reason women did not use mammography
and both women and physicians identified distance from the screening site, transportation problems and the
absence of symptoms as reasons for non-use.
Conclusion: Women are inhibited from participating in mammography screening in rural Crete. The provision
of more accessible screening services may improve this. However physician recommendation is important in
overcoming women's inhibitions. Primary care physicians serving rural areas need to be aware of barriers
preventing women from attending mammography screening and provide women with information and advice in a sensitive way so women can make informed decisions regarding breast caner screening
Inside-Out Regulation of ICAM-1 Dynamics in TNF-α-Activated Endothelium
Background: During transendothelial migration, leukocytes use adhesion molecules, such as ICAM-1, to adhere to the endothelium. ICAM-1 is a dynamic molecule that is localized in the apical membrane of the endothelium and clusters upon binding to leukocytes. However, not much is known about the regulation of ICAM-1 clustering and whether membrane dynamics are linked to the ability of ICAM-1 to cluster and bind leukocyte integrins. Therefore, we studied the dynamics of endothelial ICAM-1 under non-clustered and clustered conditions. Principal Findings: Detailed scanning electron and fluorescent microscopy showed that the apical surface of endothelial cells constitutively forms small filopodia-like protrusions that are positive for ICAM-1 and freely move within the lateral plane of the membrane. Clustering of ICAM-1, using anti-ICAM-1 antibody-coated beads, efficiently and rapidly recruits ICAM-1. Using fluorescence recovery after photo-bleaching (FRAP), we found that clustering increased the immobile fraction of ICAM-1, compared to non-clustered ICAM-1. This shift required the intracellular portion of ICAM-1. Moreover, biochemical assays showed that ICAM-1 clustering recruited beta-actin and filamin. Cytochalasin B, which interferes with actin polymerization, delayed the clustering of ICAM-1. In addition, we could show that cytochalasin B decreased the immobile fraction of clustered ICAM-1-GFP, but had no effect on non-clustered ICAM-1. Also, the motor protein myosin-II is recruited to ICAM-1 adhesion sites and its inhibition increased the immobile fraction of both non-clustered and clustered ICAM-1. Finally, blocking Rac1 activation, the formation of lipid rafts, myosin-II activity or actin polymerization, but not Src, reduced the adhesive function of ICAM-1, tested under physiological flow conditions. Conclusions: Together, these findings indicate that ICAM-1 clustering is regulated in an inside-out fashion through the actin cytoskeleton. Overall, these data indicate that signaling events within the endothelium are required for efficient ICAM-1-mediated leukocyte adhesio
Using the social entrepreneurship approach to generate innovative and sustainable malaria diagnosis interventions in Tanzania: a case study
<p>Abstract</p> <p>Background</p> <p>There have been a number of interventions to date aimed at improving malaria diagnostic accuracy in sub-Saharan Africa. Yet, limited success is often reported for a number of reasons, especially in rural settings. This paper seeks to provide a framework for applied research aimed to improve malaria diagnosis using a combination of the established methods, participatory action research and social entrepreneurship.</p> <p>Methods</p> <p>This case study introduces the idea of using the social entrepreneurship approach (SEA) to create innovative and sustainable applied health research outcomes. The following key elements define the SEA: (1) identifying a locally relevant research topic and plan, (2) recognizing the importance of international multi-disciplinary teams and the incorporation of local knowledge, (3) engaging in a process of continuous innovation, adaptation and learning, (4) remaining motivated and determined to achieve sustainable long-term research outcomes and, (5) sharing and transferring ownership of the project with the international and local partner.</p> <p>Evaluation</p> <p>The SEA approach has a strong emphasis on innovation lead by local stakeholders. In this case, innovation resulted in a unique holistic research program aimed at understanding patient, laboratory and physician influences on accurate diagnosis of malaria. An evaluation of milestones for each SEA element revealed that the success of one element is intricately related to the success of other elements.</p> <p>Conclusions</p> <p>The SEA will provide an additional framework for researchers and local stakeholders that promotes innovation and adaptability. This approach will facilitate the development of new ideas, strategies and approaches to understand how health issues, such as malaria, affect vulnerable communities.</p
Towards the clinical implementation of pharmacogenetics in bipolar disorder.
BackgroundBipolar disorder (BD) is a psychiatric illness defined by pathological alterations between the mood states of mania and depression, causing disability, imposing healthcare costs and elevating the risk of suicide. Although effective treatments for BD exist, variability in outcomes leads to a large number of treatment failures, typically followed by a trial and error process of medication switches that can take years. Pharmacogenetic testing (PGT), by tailoring drug choice to an individual, may personalize and expedite treatment so as to identify more rapidly medications well suited to individual BD patients.DiscussionA number of associations have been made in BD between medication response phenotypes and specific genetic markers. However, to date clinical adoption of PGT has been limited, often citing questions that must be answered before it can be widely utilized. These include: What are the requirements of supporting evidence? How large is a clinically relevant effect? What degree of specificity and sensitivity are required? Does a given marker influence decision making and have clinical utility? In many cases, the answers to these questions remain unknown, and ultimately, the question of whether PGT is valid and useful must be determined empirically. Towards this aim, we have reviewed the literature and selected drug-genotype associations with the strongest evidence for utility in BD.SummaryBased upon these findings, we propose a preliminary panel for use in PGT, and a method by which the results of a PGT panel can be integrated for clinical interpretation. Finally, we argue that based on the sufficiency of accumulated evidence, PGT implementation studies are now warranted. We propose and discuss the design for a randomized clinical trial to test the use of PGT in the treatment of BD
MELCHIORS: The Mercator Library of High Resolution Stellar Spectroscopy
Aims. Over the past decades, libraries of stellar spectra have been used in a large variety of science cases, including as sources of reference spectra for a given object or a given spectral type. Despite the existence of large libraries and the increasing number of projects of large-scale spectral surveys, there is to date only one very high-resolution spectral library offering spectra from a few hundred objects from the southern hemisphere (UVES-POP). We aim to extend the sample, offering a finer coverage of effective temperatures and surface gravity with a uniform collection of spectra obtained in the northern hemisphere.Methods. Between 2010 and 2020, we acquired several thousand echelle spectra of bright stars with the Mercator-HERMES spectrograph located in the Roque de Los Muchachos Observatory in La Palma, whose pipeline offers high-quality data reduction products. We have also developed methods to correct for the instrumental response in order to approach the true shape of the spectral continuum. Additionally, we have devised a normalisation process to provide a homogeneous normalisation of the full spectral range for most of the objects.Results. We present a new spectral library consisting of 3256 spectra covering 2043 stars. It combines high signal-to-noise and high spectral resolution over the entire range of effective temperatures and luminosity classes. The spectra are presented in four versions: raw, corrected from the instrumental response, with and without correction from the atmospheric molecular absorption, and normalised (including the telluric correction)
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