232 research outputs found
Optimal packetisation of MPEG-4 using RTP over mobile networks
The introduction of third-generation wireless networks should result in real-time mobile
video communications becoming a reality. Delivery of such video is likely to be facilitated by the realtime
transport protocol (RTP). Careful packetisation of the video data is necessary to ensure the
optimal trade-off between channel utilisation and error robustness. Theoretical analyses for two basic
schemes of MPEG-4 data encapsulation within RTP packets are presented. Simulations over a GPRS
(general packet radio service) network are used to validate the analysis of the most efficient scheme.
Finally, a motion adaptive system for deriving MPEG-4 video packet sizes is presented. Further
simulations demonstrate the benefits of the adaptive system
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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 servicesā adherence to aphasia best practice recommendations
Optical identification of XMM sources in the CFHTLS
We present optical spectroscopic identifications of X-ray sources in ~3
square degrees of the XMM-Large Scale Structure survey (XMM-LSS), also covered
by the Canada France Hawaii Telescope Legacy Survey (CFHTLS), obtained with the
AAOmega instrument at the Anglo Australian Telescope. In a flux limited sample
of 829 point like sources in the optical band with g' <~22 mag and the 0.5-2
keV flux > 1x10^{-15}erg/cm^2/s, we observed 695 objects and obtained reliable
spectroscopic identification for 489 sources, ~59% of the overall sample. We
therefore increase the number of identifications in this field by a factor
close to five. Galactic stellar sources represent about 15% of the total
(74/489). About 55% (267/489) are broad-line Active Galactic Nuclei (AGNs)
spanning redshifts between 0.15 and 3.87 with a median value of 1.68. The
optical-to-X-ray spectral index of the broad-line AGNs is 1.47, typical of
optically-selected Type I quasars and is found to correlate with the rest frame
X-ray and optical monochromatic luminosities at 2 keV and 2500 angstroms
respectively. Consistent with previous studies, we find alpha_ox not to be
correlated with z. In addition, 32 and 116 X-ray sources are, respectively
absorption and emission-line galaxies at z<0.76. From a line ratio diagnostic
diagram it is found that in about 50% of these emission line galaxies, the
emission lines are powered significantly by the AGN. Thirty of the XMM sources
are detected at one or more radio frequencies. In addition, 24 sources have
ambiguous identification: in 8 cases, two XMM sources have a single optical
source within 6 arcsecs of each of them, whereas, 2 and 14 XMM sources have,
respectively, 3 and 2 possible optical sources within 6 arcsecs of each of
them.Comment: 15 pages, 14 figures, 5 tables, accepted for publication in MNRA
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Health-related quality of life in people with aphasia: Implications for fluency disorders quality of life research
Abstract
It is increasingly important that clinicians address the health-related quality of life (HRQOL) of adults with communication disorders in clinical practice. The overall aim of this paper is to draw conclusion about the suitability of the Short Form 36 Health Survey for the communication disorders of aphasia and stuttering. This study reports on the impact of post-stroke aphasia on 30 Australian older adultsā HRQOL. It also comments on the capacity of the SF-36 to measure HRQOL in this population, specifically whether it is sensitive to the three known determinants of post-stroke HRQOL ā emotional, physical and social functioning. Comparisons with other data are made to assist interpretation of the SF-36 subscale scores: with 75 older adults with no history of neurological conditions; and with data from the 1995 National Health Survey data. The main findings are: (1) adults with post-stroke aphasia have similar HRQOL to their peers on six subscales, but significantly lower Role emotional and Mental health HRQOL; (2) a substantial number of aphasic adults reported depressive mood; and (3) aphasic adults with depressive mood have significantly worse HRQOL on six subscales than aphasic adults without depressive mood, but similar Role emotional and Body pain HRQOL. In conclusion, stroke and aphasia have minimal impact on older adultsā HRQOL as measured by the SF-36, which conflicts with an established evidence base of the negative consequences of aphasia on life. Thus, the SF-36 is not advisable for use with aphasic adults. Implications of these findings for aphasia and stuttering are discussed.
Educational objectives: The reader will be able to: (a) describe the impact of aphasia and depressive mood on quality of life; (b) compare the impact of aphasia on the quality of life of adults to adults who do not have aphasia; (c) describe the similarities and differences between quality of life of adults with aphasia and adults who stutter; and (d) describe the strengths and limitations of the SF-36 as a measure of quality of life in adults who stutter versus adults with aphasia
A method for extracting calibrated volatility information from the FIGAERO-HR-ToF-CIMS and its experimental application
The Filter Inlet for Gases and AEROsols (FIGAERO) is an inlet specifically designed to be coupled with the Aerodyne High-Resolution Time-of-Flight Chemical Ionization Mass Spectrometer (HR-ToF-CIMS). The FIGAERO-HR-ToF-CIMS provides simultaneous molecular information relating to both the gas- and particle-phase samples and has been used to extract vapour pressures (VPs) of the compounds desorbing from the filter whilst giving quantitative concentrations in the particle phase. However, such extraction of vapour pressures of the measured particle-phase components requires use of appropriate, well-defined, reference compounds. Vapour pressures for the homologous series of polyethylene glycols (PEG) ((H-(O-CH2CH2)n-OH) for n = 3 to n = 8), covering a range of vapour pressures (VP) (10-1 to 10-7 Pa) that are atmospherically relevant, have been shown to be reproduced well by a range of different techniques, including Knudsen Effusion Mass Spectrometry (KEMS). This is the first homologous series of compounds for which a number of vapour pressure measurement techniques have been found to be in agreement, indicating the utility as a calibration standard, providing an ideal set of benchmark compounds for accurate characterization of the FIGAERO for extracting vapour pressure of measured compounds in chambers and the real atmosphere. To demonstrate this, single-component and mixture vapour pressure measurements are made using two FIGAERO-HR-ToF-CIMS instruments based on a new calibration determined from the PEG series. VP values extracted from both instruments agree well with those measured by KEMS and reported values from literature, validating this approach for extracting VP data from the FIGAERO. This method is then applied to chamber measurements, and the vapour pressures of known products are estimated
The impact of a hybrid social marketing intervention on inequities in access, ownership and use of insecticide-treated nets
BACKGROUND: An ITN intervention was initiated in three predominantly rural districts of Eastern Province, Zambia, that lacked commercial distribution and communication infrastructures. Social marketing techniques were used for product and message development. Public sector clinics and village-based volunteers promoted and distributed subsidized ITNs priced at $2.5 per net. A study was conducted to assess the effects of the intervention on inequities in knowledge, access, ownership and use of ITNs. METHODS: A post-test only quasi-experimental study design was used to compare intervention and comparison districts. A total of 2,986 respondents were interviewed. Survey respondents were grouped into four socio-economic (SES) categories: low, medium-low, medium and high. Knowledge, access, ownership and use indicators are compared. Concentration index scores are calculated. Interactions between intervention status and SES help determine how different SES groups benefited from the intervention. RESULTS: Although overall use of nets remained relatively low, post-test data show that knowledge, access, ownership and use of mosquito nets was higher in intervention districts. A decline in SES inequity in access to nets occurred in intervention districts, resulting from a disproportionately greater increase in access among the low SES group. Declines in SES inequities in net ownership and use of nets were associated with the intervention. The largest increases in net ownership and use occurred among medium and high SES categories. CONCLUSION: Increasing access to nets among the poorest respondents in rural areas may not lead to increases in net use unless the price of nets is no longer a barrier to their purchase
Social participation for older people with aphasia: The impact of communication disability on friendships
Purpose: The language changes experienced by a person with aphasia following a stroke often have sudden and long-lasting negative impact on friendships. Friendship relationships are core to social engagement, quality of life, and emotional well-being. The aims of this study were to describe everyday communication with friends for older people with and without aphasia and to examine the nature of actual friendship conversations involving a person with aphasia. Method: This naturalistic inquiry drew data from two phases of research: a participant observation study of 30 older Australians, 15 of whom had aphasia following a stroke, and a collective case study using stimulated recall to examine friendship conversations involving an older person with aphasia. Results: People with aphasia communicated with fewer friends and had smaller social networks. "Friendship" was a core domain of communication for older people and participation in leisure and educational activities was focal in everyday communication with friends. Case study data of conversations between three older people with aphasia and their friends illuminated features of "time," the role of humour, and friends having shared interests. Conclusion: Aphasia has been found to impact on friendships. A need exists for research and intervention programs to address communication with friends for older people with aphasia
Integrating aphasia into stroke best practices: A Canadian KTE strategy
This poster reports on the activities to date of the Stroke and Aphasia Canada team including results of a Canadian Institutes of Health Research (CIHR) Knowledge Translation (KT) planning grant (grant #290592, 2013)
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Which outcomes are most important to people with aphasia and their families? an international nominal group technique study framed within the ICF
PURPOSE: To identify important treatment outcomes from the perspective of people with aphasia and their families using the ICF as a frame of reference.
METHODS: The nominal group technique was used with people with aphasia and their family members in seven countries to identify and rank important treatment outcomes from aphasia rehabilitation. People with aphasia identified outcomes for themselves; and family members identified outcomes for themselves and for the person with aphasia. Outcomes were analysed using qualitative content analysis and ICF linking.
RESULTS: A total of 39 people with aphasia and 29 family members participated in one of 16 nominal groups. Inductive qualitative content analysis revealed the following six themes: (1) Improved communication; (2) Increased life participation; (3) Changed attitudes through increased awareness and education about aphasia; (4) Recovered normality; (5) Improved physical and emotional well-being; and (6) Improved health (and support) services. Prioritized outcomes for both participant groups linked to all ICF components; primary activity/participation (39%) and body functions (36%) for people with aphasia, and activity/participation (49%) and environmental factors (28%) for family members. Outcomes prioritized by family members relating to the person with aphasia, primarily linked to body functions (60%).
CONCLUSIONS: People with aphasia and their families identified treatment outcomes which span all components of the ICF. This has implications for research outcome measurement and clinical service provision which currently focuses on the measurement of body function outcomes. The wide range of desired outcomes generated by both people with aphasia and their family members, highlights the importance of collaborative goal setting within a family-centred approach to rehabilitation. These results will be combined with other stakeholder perspectives to establish a core outcome set for aphasia treatment research. Implications for Rehabilitation Important outcomes for people with aphasia and their families span all components of the ICF. The relevancy and translation of research findings may be increased by measuring and reporting research outcomes which are important to people living with aphasia. The results of this study indicate that important treatment outcomes for people living with aphasia most frequently link to the activity/participation and body function components of the ICF. The outcomes identified in this study suggest a broad role for clinicians working in aphasia rehabilitation. The categories of identified outcomes may be used clinically as a starting point in goal-setting discussions with clients and their families
Chemical characterisation of benzene oxidation products under high- and low-NOx conditions using chemical ionisation mass spectrometry
Aromatic hydrocarbons are a class of volatile organic compounds associated with anthropogenic activity and make up a significant fraction of urban volatile organic compound (VOC) emissions that contribute to the formation of secondary organic aerosol (SOA). Benzene is one of the most abundant species emitted from vehicles, biomass burning and industry. An iodide time-of-flight chemical ionisation mass spectrometer (ToF-CIMS) and nitrate ToF-CIMS were deployed at the Julich Plant Atmosphere Chamber as part of a series of experiments examining benzene oxidation by OH under high- and low-NOx conditions, where a range of organic oxidation products were detected. The nitrate scheme detects many oxidation products with high masses, ranging from intermediate volatile organic compounds (IVOCs) to extremely low volatile organic compounds (ELVOCs), including C-12 dimers. In comparison, very few species with C->= 6 and O-> 8 were detected with the iodide scheme, which detected many more IVOCs and semi-volatile organic compounds (SVOCs) but very few ELVOCs and low volatile organic compounds (LVOCs). A total of 132 and 195 CHOPeer reviewe
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