791 research outputs found
Diffraction-limited Subaru imaging of M82: sharp mid-infrared view of the starburst core
We present new imaging at 12.81 and 11.7 microns of the central ~40"x30"
(~0.7x0.5 kpc) of the starburst galaxy M82. The observations were carried out
with the COMICS mid-infrared (mid-IR) imager on the 8.2m Subaru telescope, and
are diffraction-limited at an angular resolution of <0".4. The images show
extensive diffuse structures, including a 7"-long linear chimney-like feature
and another resembling the edges of a ruptured bubble. This is the clearest
view to date of the base of the kpc-scale dusty wind known in this galaxy.
These structures do not extrapolate to a single central point, implying
multiple ejection sites for the dust. In general, the distribution of dust
probed in the mid-IR anticorrelates with the locations of massive star clusters
that appear in the near-infrared. The 10-21 micron mid-IR emission,
spatially-integrated over the field of view, may be represented by hot dust
with temperature of ~160 K. Most discrete sources are found to have extended
morphologies. Several radio HII regions are identified for the first time in
the mid-IR. The only potential radio supernova remnant to have a mid-IR
counterpart is a source which has previously also been suggested to be a weak
active galactic nucleus. This source has an X-ray counterpart in Chandra data
which appears prominently above 3 keV and is best described as a hot (~2.6 keV)
absorbed thermal plasma with a 6.7 keV Fe K emission line, in addition to a
weaker and cooler thermal component. The mid-IR detection is consistent with
the presence of strong [NeII]12.81um line emission. The broad-band source
properties are complex, but the X-ray spectra do not support the active
galactic nucleus hypothesis. We discuss possible interpretations regarding the
nature of this source.Comment: Accepted for publication in PASJ Subaru special issue. High
resolution version available temporarily at
http://www.astro.isas.jaxa.jp/~pgandhi/pgandhi_m82.pd
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Increasing the intensity and comprehensiveness of aphasia services: identification of key factors influencing implementation across six countries
Background: Aphasia services are currently faced by increasing evidence for therapy of greater intensity and comprehensiveness. Intensive Comprehensive Aphasia Programs (ICAPs) combine these elements in an evidence-based, time-limited group program. The incorporation of new service delivery models in routine clinical practice is, however, likely to pose challenges for both the service provider and administering clinicians. This program of research aims to identify these challenges from the perspective of aphasia clinicians from six countries and will seek to trial potential solutions. Continual advancements in global communication technologies suggest that solutions will be easily shared and accessed across multiple countries.
Aims: To identify the perceived and experienced barriers and facilitators to the implementation of 1) intensive aphasia services, 2) comprehensive aphasia services, and 3) ICAPs, from aphasia clinicians across six countries.
Methods and procedures: A qualitative enquiry approach included data from six focus groups (n = 34 participants) in Australia, New Zealand, Canada, United States of America (USA), United Kingdom (UK), and Ireland. A thematic analysis of focus group data was informed by the Theoretical Domains Framework (TDF).
Outcomes and results: Five prominent theoretical domains from the TDF influenced the implementation of all three aphasia service types across participating countries: environmental context and resources, beliefs about consequences, social/professional role and identity, skills, and knowledge. Four overarching themes assisted the identification and explanation of the key barriers and facilitators: 1. Collaboration, joint initiatives and partnerships, 2. Advocacy, the promotion of aphasia services and evidence-based practice, 3. Innovation, the ability to problem solve challenges, and 4. Culture, the influence of underlying values.
Conclusions: The results of this study will inform the development of a theoretically informed intervention to improve health servicesâ adherence to aphasia best practice recommendations
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An international perspective. A survey of clinician views and practices from 16 countries
Objective: To gain an insight into speech and language therapistsâ perspectives and practices on quality of life in aphasia.
Participants and Methods: The International Association of Logopedics and Phoniatrics Aphasia Committee developed a survey questionnaire, which was delivered on-line, anonymously, through SurveyMonkey (November 2012 â April 2013) to clinicians working with people with aphasia in 16 countries across the world.
Results: A large number of speech and language therapists responded to the survey, with 19/21 questions answered by 385 â 579 participants. Clinicians were well informed on what constitutes quality of life and viewed it as a complex construct influenced by health, participation, in/dependence, communication, personal factors, and environmental factors. In their clinical practice, they considered quality of life as important, used informal approaches to explore it and aimed to address quality of life goals; yet the majority did not evaluate quality of life in a systematic way.
Conclusion: There is a need for training on quality of life to facilitate speech and language therapists to incorporate quality of life outcome measures in their interventions. There is also a need for further research on what interventions improve quality of life in aphasia
Reducing the psychosocial impact of aphasia on mood and quality of life in people with aphasia and the impact of caregiving in family members through the Aphasia Action Success Knowledge (Aphasia ASK) program: Study protocol for a randomized controlled trial
© 2016 Worrall et al. Background: People with aphasia and their family members are at high risk of experiencing post stroke depression. The impact of early interventions on mood and quality of life for people with aphasia is unknown. Methods/design: This study will determine whether an early intervention for both the person with aphasia after stroke and their family members leads to better mood and quality of life outcomes for people with aphasia, and less caregiver burden and better mental health for their family members. This is a multicenter, cluster-randomized controlled trial. Clusters, which are represented by Health Service Districts, will be randomized to the experimental intervention (Aphasia Action Success Knowledge Program) or an attention control (Secondary Stroke Prevention Information Program). People with aphasia and their family members will be blinded to the study design and treatment allocation (that is, will not know there are two arms to the study). Both arms of the study will receive usual care in addition to either the experimental or the attention control intervention. A total of 344 people with aphasia and their family members will be recruited. Considering a cluster size of 20, the required sample size can be achieved from 18 clusters. However, 20 clusters will be recruited to account for the potential of cluster attrition during the study. Primary outcome measures will be mood and quality of life of people with aphasia at 12 months post stroke. Secondary measures will be family member outcomes assessing the impact of caregiving and mental health, and self-reported stroke risk-related behaviors of people with aphasia. Discussion: This is the first known program tailored for people with aphasia and their family members that aims to prevent depression in people with aphasia by providing intervention early after the stroke. Trial registration: This trial is registered in the Australian New Zealand Clinical Trials Registry (ANZCTR) as ACTRN12614000979651. Date registered: 11 September 2014
The Chandra X-ray Observatory Resolves the X-ray Morphology and Spectra of a Jet in PKS 0637-752
The core-dominated radio-loud quasar PKS 0637-752 (z = 0.654) was the first
celestial object observed with the Chandra X-ray Observatory, offering the
early surprise of the detection of a remarkable X-ray jet. Several observations
with a variety of detector configurations contribute to a total exposure time
with the Chandra Advanced CCD Imaging Spectrometer (ACIS; Garmire et al. 2000,
in preparation) of about 100ks. A spatial analysis of all the available X-ray
data, making use of Chandra's spatial resolving power of about 0.4 arcsec,
reveals a jet that extends about 10 arcsec to the west of the nucleus. At least
four X-ray knots are resolved along the jet, which contains about 5% of the
overall X-ray luminosity of the source. Previous observations of PKS 0637-752
in the radio band (Tingay et al. 1998) had identified a kpc-scale radio jet
extending to the West of the quasar. The X-ray and radio jets are similar in
shape, intensity distribution, and angular structure out to about 9 arcsec,
after which the X-ray brightness decreases more rapidly and the radio jet turns
abruptly to the north. The X-ray luminosity of the total source is log Lx ~
45.8 erg/s (2 - 10keV), and appears not to have changed since it was observed
with ASCA in November 1996. We present the results of fitting a variety of
emission models to the observed spectral distribution, comment on the
non-existence of emission lines recently reported in the ASCA observations of
PKS 0637-752, and briefly discuss plausible X-ray emission mechanisms.Comment: 24 pages, includes 8 figures, Accepted for publication in Ap
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Preliminary Psychometric Analyses of Two Assessment Measures Quantifying Communicative and Social Activities: the COMACT and SOCACT
Background: There is a need for clinical tools that capture the real-life impact of aphasia (Simmons-Mackie, Threats & Kagan, 2005). This study reports on a psychometric investigation of two self-report tools: the Communicative Activities Checklist and the Social Activities Checklist (COMACT; SOCACT: Cruice, 2001), which assess the dimensions of communication activity and social participation in aphasia.
Aims: (1) To investigate internal consistency, convergent and known validity of the COMACT and SOCACT; and (2) To investigate the impact of personal contextual factors: gender, age, years in education, linguistic ability and emotional health on communicative and social activities.
Method: 30 participants with mild-moderate chronic aphasia (PWA: mean age 71 years, mean time post-onset 41 months, mean years in education 10.77) and 75 control neurologically healthy participants (NHP: mean age 74 years, mean years in education 13.18) completed the COMACT and SOCACT reporting how frequently they engaged in particular activities. The COMACT has 45 communication activities with sub-scales of Talking, Listening, Reading and Writing. The SOCACT contains 20 social activities with sub-scales of Leisure, Informal and Formal. Internal consistency (IC) was examined using Cronbachâs alpha (α). Correlations with published assessments, Western Aphasia Battery (WAB: Kertesz, 1982) and Communication Activities of Daily Living (CADL-2: Holland, Frattali & Fromm, 1999) were computed for COMACT only. Multiple regression models were examined for differences in participant (PWA vs. NHP) performance on COMACT and SOCACT. COMACT & SOCACT: psychometric investigation
Results: Total COMACT IC was 0.83 (PWA), and 0.84 (NHP). Following deletion of four items, to further improve sub-scale ICs, total COMACT IC was 0.83 (PWA) and 0.86 (NHP). COMACT total score and WAB AQ were moderately correlated (r = 0.55). Total SOCACT IC was 0.58 (PWA) and 0.63 (NHP). Following single item deletion, total IC was 0.65 (PWA) and 0.64 (NHP). Statistical analysis revealed PWA, in comparison to NHP, participated in significantly fewer communication and social activities. Personal contextual factors impacted both groups differently; particular aspects were associated with communication activity (age and language severity) and social activity (age only). For NHP, ageing, emotional health and years in education were significant predictors of social and communication activity.
Conclusion: This study finds the COMACT to be a reliable, valid measure of communication activity. The SOCACT had âquestionableâ IC and requires further psychometric investigation. Both tools demonstrate known group validity. Relationships between impairment-level and personal contextual factors for communication activity and social participation are highlighted
Establishing consensus on a definition of aphasia: an e-Delphi study of international aphasia researchers
Background : Definitions reflect the current state of knowledge about a health condition. An agreed definition of aphasia is central to the progression of the science and clinical practice relevant to aphasia.
Aim : To establish consensus on a definition of aphasia.
Methods & Procedures : A three-round modified e-Delphi study was conducted with aphasia researchers who were members of the Collaboration of Aphasia Trialists (CATs). In round one, participants were provided with a draft definition developed by the Societal Impact and Reintegration Working Group of CATs. Participants were asked whether they agreed with the definition and were asked to comment on any aspects that they perceived to require amendment. Comments were collated and analysed using inductive content analysis. In round two, participants were presented with the collated and de-identified results of the first round and the participants were asked to vote âyes/noâ on two contentious aspects of the definition. In round three, agreement on the revised definition was again sought using closed âyes/noâ voting. Consensus was defined a priori as at least 70% agreement by 80% of all CATs members. CATs membership fluctuated across the study period and ranged between 131 and 141 members.
Outcomes & Results : The proposed definition was Aphasia is a communication disability due to an acquired impairment of language modalities caused by focal brain damage. Aphasia may affect participation and quality of life of the person with aphasia as well as their family and friends. Aphasia masks competence and affects functioning across relationships, life roles and activities, thereby influencing social inclusion, social connectedness, access to information and services, equal rights, and wellbeing in family, community and culture.
Two main categories of proposed amendments to the definition were identified: (1) definition of aphasia as a communication disability versus a language impairment; and (2) definition of aphasia as being the result of a focal and/or diffuse lesion. After three rounds of surveys, consensus was unable to be achieved with an almost even split across participants on both amendment issues.
Conclusion : Further debate about the use of the term communication disability to describe aphasia and whether aphasia is a result of focal or diffuse lesions is required before consensus is again attempted
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Lunar Subsurface Exploration Technologies at the University of Glasgow: capabilities and the âi-Drillâ case study
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