10,884 research outputs found
Playing to Live: Outcome Evaluation of a Community-Based Psychosocial Expressive Arts Program for Children During the Liberian Ebola Epidemic
Background. This paper reviews the efficacy of a community psychosocial arts program focused on building mental health capacity within post-Ebola Liberia. The aim of this paper was to evaluate the outcome effects of two groups using pre- and post-treatment data. We hypothesized that there would be a difference in symptoms pre- and post-treatment, and the longer program would yield more significant results.
Methods. There was a total of 870 child participants. Of 40 sites, 24 were selected for a 5-month treatment (TG1) while the remaining 16 sites received 3 months of treatment (TG2). Paired t tests and a mixed-model analysis of variance (ANOVA) were used to analyse pre- and post-psychological stress symptoms (PSS) for samples from both groups.
Results. Separately, treatment group 1 (TG1) and treatment group 2\u27s (TG2) paired t test yielded significant results (p \u3c 0.001) for the decrease of PSS. The mixed-model ANOVA found that there were significant differences in total pre- and post-test PSS and a significant difference in PSS means over time.
Conclusions. Results indicated that there was a statistically significant decrease in reported symptoms in both treatment groups pre- to post-intervention and a significant difference in total symptoms over time. However, the findings do not indicate that the longer programming was statistically different compared to the shorter programming. The study presented had gaps in data, largely due to limits in research during the crisis. However, this paper provides a unique case study for challenges that can be faced for project evaluation in emergency settings
Unveiling the nature of IGR J16283-4838
Context. One of the most striking discoveries of the INTEGRAL observatory is
the existence of a previously unknown population of X-ray sources in the inner
arms of the Galaxy. The investigations of the optical/NIR counterparts of some
of them have provided evidence that they are highly absorbed high mass X-ray
binaries hosting supergiants. Aims. We aim to identify the optical/NIR
counterpart of one of the newly discovered INTEGRAL sources, IGR J16283-4838,
and determine the nature of this system. Methods. We present optical and NIR
observations of the field of IGR J16283-4838, and use the astrometry and
photometry of the sources within it to identify its counterpart. We obtain its
NIR spectrum, and its optical/NIR spectral energy distribution by means of
broadband photometry. We search for the intrinsic polarization of its light,
and its short and long-term photometric variability. Results. We demonstrate
that this source is a highly absorbed HMXB located beyond the Galactic center,
and that it may be surrounded by a variable circumstellar medium.Comment: 6 pages, 5 figures, accepted for publication in Astronomy &
Astrophysic
Evolution of an ancient protein function involved in organized multicellularity in animals.
To form and maintain organized tissues, multicellular organisms orient their mitotic spindles relative to neighboring cells. A molecular complex scaffolded by the GK protein-interaction domain (GKPID) mediates spindle orientation in diverse animal taxa by linking microtubule motor proteins to a marker protein on the cell cortex localized by external cues. Here we illuminate how this complex evolved and commandeered control of spindle orientation from a more ancient mechanism. The complex was assembled through a series of molecular exploitation events, one of which - the evolution of GKPID's capacity to bind the cortical marker protein - can be recapitulated by reintroducing a single historical substitution into the reconstructed ancestral GKPID. This change revealed and repurposed an ancient molecular surface that previously had a radically different function. We show how the physical simplicity of this binding interface enabled the evolution of a new protein function now essential to the biological complexity of many animals
The aetiology and clinical characteristics of cryptococcal infections in Far North Queensland, tropical Australia
Cryptococcal infections are an important cause of morbidity and mortality in tropical Australia. This retrospective audit was conducted to characterise the aetiology, temporospatial epidemiology, and clinical course of 49 cryptococcal infections in Far North Queensland between 1 January 1999 and 31 December 2019. Cryptococcus gattii was identified in 15/ 32 (47%) in whom it was possible to speciate the organism. Among these 15 patients, 13 (87%) had a rural residential address, 10 (67%) were Indigenous Australians and 11 (73%) presented during the May-November dry season. When compared to the 17 patients with Cryptococcus neoformans infection, patients with C. gattii were less likely to be immunocompromised (0/15 versus 8/17 (47%), p = 0.003). Neurosurgery was necessary in 5/15 C. gattii cases and 3/17 (18%) C. neoformans cases (p = 0.42). Outcomes were generally good with 42/49 (86%) cases-and 14/15 (93%) with C. gattii infection-surviving to hospital discharge. These positive outcomes are likely to be explained by the development of standardised treatment guidelines during the study period, low rates of comorbidity in the patients with C. gattii infection and access to liposomal amphotericin and neurosurgical support in the well-resourced Australian healthcare system
Unveiling the nature of six HMXBs through IR spectroscopy
The International Gamma-Ray Astrophyiscs Laboratory (INTEGRAL) is discovering
a large number of new hard X-ray sources, many of them being HMXBs. The
identification and spectral characterization of their optical/infrared
counterparts is a necessary step to undertake detailed study of these systems.
In particular, the determination of the spectral type is crucial in the case of
the new class of Supergiant Fast X-ray Transients (SFXTs), which show X-ray
properties common to other objects. We used the ESO/NTT SofI spectrograph to
observe proposed IR counterparts to HMXBs, obtaining Ks medium resolution
spectra (R = 1320) with a S/N >= 100. We classified them through comparison
with published atlases. We were able to spectrally classify the six sources.
This allowed us to ascribe one of them to the new class of SFXTs and confirm
the membership of two sources to this class. We confirmed the spectral
classification, derived from optical spectroscopy, of a known system, 4U
1907-09, showing for the first time its infrared spectrum. The spectral
classification was also used to estimate the distance of the sources. We
compared the extinction as derived from X-ray data with effective interstellar
extinction obtained from our data, discussing the absorption component due to
the circumstellar environment, which we observed in four systems; in
particular, intrinsic absorption seems to emerge as a typical feature of the
entire class of SFXTs.Comment: 8 pages, 6 figures, 3 tables, accepted for publication in Astronomy &
Astrophysic
Orbital dynamics of Cygnus X-3
Orbital-phased-resolved infrared spectra of Cygnus X-3 in outburst and
quiescence, including tomographic analysis, are presented. We confirm the
phasing of broad HeII and NV lines in quiescence, such that maximum blue shift
corresponds to the X-ray minimum at phase = 0.00 +/- 0.04. In outburst,
double-peaked HeI structures show a similar phasing with two significant
differences: (a) although varying in relative strength, there is continuous
line emission in blue and red peaks around the orbit, and (b) an absorption
component, ~1/4 of an orbit out of phase with the emission features, is
discerned. Doppler tomograms of the double-peaked profiles are consistent with
a disk-wind geometry, rotating at velocities of 1000 km/s. Regrettably, the
tomography algorithm will produce a similar ring structure from alternative
line sources if contaminated by overlying P Cygni profiles. This is certainly
the case in the strong 2.0587 micron HeI line, leading to an ambiguous solution
for the nature of double-peaked emission. The absorption feature, detected 1/4
of an orbit out of phase with the emission features, is consistent with an
origin in the He star wind and yields for the first time a plausible radial
velocity curve for the system. We directly derive the mass function of the
system, 0.027 M_sun. If we assume a neutron star accretor and adopt a high
orbital inclination, i > 60 degrees, we obtain a mass range for the He star of
5 M_sun < M_WR < 11 M_sun. Alternatively if the compact object is a black hole,
we estimate M_BH < 10 M_sun. We discuss the implications of these masses for
the nature and size of the binary system.Comment: Accepted for publication in ApJ main journa
Optical photometric GTC/OSIRIS observations of the young massive association Cygnus OB2
In order to fully understand the gravitational collapse of molecular clouds,
the star formation process and the evolution of circumstellar disks, these
phenomena must be studied in different Galactic environments with a range of
stellar contents and positions in the Galaxy. The young massive association
Cygnus OB2, in the Cygnus-X region, is an unique target to study how star
formation and the evolution of circumstellar disks proceed in the presence of a
large number of massive stars. We present a catalog obtained with recent
optical observations in r,i,z filters with OSIRIS, mounted on the GTC
telescope, which is the deepest optical catalog of Cyg OB2 to date.
The catalog consist of 64157 sources down to M=0.15 solar masses at the
adopted distance and age of Cyg OB2. A total of 38300 sources have good
photometry in all three bands. We combined the optical catalog with existing
X-ray data of this region, in order to define the cluster locus in the optical
diagrams. The cluster locus in the r-i vs. i-z diagram is compatible with an
extinction of the optically selected cluster members in the 2.64<AV<5.57 range.
We derive an extinction map of the region, finding a median value of AV=4.33 in
the center of the association, decreasing toward the north-west. In the
color-magnitude diagrams, the shape of the distribution of main sequence stars
is compatible with the presence of an obscuring cloud in the foreground at
about 850+/-25 pc from the Sun.Comment: Accepted for publication ApJS 201
Reducing the impacts of leg hold trapping on critically endangered foxes by modified traps and conditioned trap aversion on San Nicolas Island, California, USA
Padded leg-hold live traps were used as the primary removal technique in the successful eradication of feral cats Felis silvestris catus from San Nicolas Island, California, USA. Risk of injury to endemic San Nicolas Island foxes Urocyon littoralis dickeyi, a similarly sized and more abundant non-target species, was mitigated by using a smaller trap size, modifying the trap and trap set to reduce injuries, and utilising a trap monitoring system to reduce time animals spent in traps. Impacts to foxes during the eradication campaign were further reduced by having a mobile veterinary hospital on island to treat injured foxes. Compared to other reported fox trapping efforts, serious injuries were reduced 2-7 times. Trapping efforts exceeded animal welfare standards, with 95% of fox captures resulting in minor or no injuries. Older foxes were more likely to receive serious injury. Fox captures were also reduced through aversive conditioning, with initial capture events providing a negative stimulus to prevent recaptures. Fox capture rates decreased up to six times during seven months of trapping, increasing trap availability for cats, and improving the efficacy of the cat eradication program. No aspect of the first capture event was significantly linked to the chance of recapture
Predicting the public health benefit of vaccinating cattle against Escherichia coli O157
Identifying the major sources of risk in disease transmission is key to designing effective controls. However, understanding of transmission dynamics across species boundaries is typically poor, making the design and evaluation of controls particularly challenging for zoonotic pathogens. One such global pathogen is Escherichia coli O157, which causes a serious and sometimes fatal gastrointestinal illness. Cattle are the main reservoir for E. coli O157, and vaccines for cattle now exist. However, adoption of vaccines is being delayed by conflicting responsibilities of veterinary and public health agencies, economic drivers, and because clinical trials cannot easily test interventions across species boundaries, lack of information on the public health benefits. Here, we examine transmission risk across the cattle–human species boundary and show three key results. First, supershedding of the pathogen by cattle is associated with the genetic marker stx2. Second, by quantifying the link between shedding density in cattle and human risk, we show that only the relatively rare supershedding events contribute significantly to human risk. Third, we show that this finding has profound consequences for the public health benefits of the cattle vaccine. A naïve evaluation based on efficacy in cattle would suggest a 50% reduction in risk; however, because the vaccine targets the major source of human risk, we predict a reduction in human cases of nearly 85%. By accounting for nonlinearities in transmission across the human–animal interface, we show that adoption of these vaccines by the livestock industry could prevent substantial numbers of human E. coli O157 cases
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