88 research outputs found
Implant technology and TFS processing in relation to speech discrimination and music perception and appreciation
Direct stimulation of the auditory nerve via a Cochlear Implant (CI) enables profoundly deaf subjects to perceive sounds. Many CI users find language comprehension satisfactory in quiet and accessible in the presence of noise. However, music contains different dimensions which need to be approached in different ways. Whilst both language and music take advantage of the modulation of acoustic parameters to convey information, music is an acoustically more complex stimulus than language, demanding more complex resolution mechanisms.
One of the most important aspects that contributes to speech perception skills, especially when listening in a fluctuating background, is Temporal Fine Structure processing. TFS cues are pre-dominant in conveying Low Frequency (LF) signals. Harmonic (HI) and Disharmonic (DI) In-tonation are tests of pitch perception in the LF domain which are thought to depend on avail-ability of TFS cues and which are included in the protocol on this group of adult CI recipients.
One of the primary aims of this thesis was the production of a new assessment tool, the Italian STARR test which was based on the measurement of speech perception using a roving-level adaptive method where the presentation level of both speech and noise signals varied between each sentence presentation. The STARR test attempts to reflect a better representation of real world listening conditions where background noise is usually present and speech intensity var-ies according to vocal capacity as well as the distance of the speaker. The outcomes for the Italian STARR in NH adults were studied to produce normative data, as well as to evaluate inter-list variability and learning effects. (Chapter 4).
The second aim was to investigate LF pitch perception outcomes linked to availability of TFS cues in a group of adult CI recipients including bimodal users in relation to speech perception, in particular Italian STARR outcomes. Here it was seen that age had a significant effect on performance especially in older adults. Similarly, CI recipients (even better performers) showed abnormal findings in comparison to NH subjects. On the other hand, the significant effect of CI thresholds re-emphasized the sensitivity of the test to low intensity speech which a CI user can often encounter under everyday listening conditions. Statistically significant correlations between HI/DI and STARR performance were found. Moreover, bimodal benefit was seen both for HI/DI and STARR tests. Overall findings confirmed the usefulness of evaluating both LF pitch and speech perception in noise in order to track changes in TFS sen-sitivity for CI recipients over time and across different listening conditions which might be provided by future technological progress. (Chapter 5)
Finally, the last and main aspect taken into account in this thesis was the study of the difficul-ties experienced by CI users when listening to music. An attempt was made to correlate find-ings resulting from the previous phases of this study both to Speech in Noise and to the com-plex subjective aspects of Music Perception and Appreciation: correlation analysis between HI/DI tests and the main dimensions of Speech in Noise (STARR and OLSA) and Music Ap-preciation was performed. (Chapter 6). Interestingly, positive findings were found for the two most complex types of Music (Classical, Jazz), whereas Soul did not seem to require particular competence in Pitch perception for the appreciation of the subjective variables taken into con-sideration by this study
Health literacy: Patients' texts, context and mediation
Health literacy encompasses people’s knowledge, motivation and competences to access, understand, appraise and apply health information to make judgments and take decisions in every-day life concerning health care, disease prevention and health promotion (Kickbusch et al., 2013). Research in health literacy has grown in prominence as a separate entity over the last twenty years, partly in response to the growth of chronic disease requiring greater patient self-management. Research has found significant relationships between reading comprehension levels and different health outcomes and health behaviours, with reading comprehension being used as a way to measure health literacy despite its accepted definition being much broader. However, there has been little research which takes a social practices perspective on health literacy.
In this thesis, health literacy is viewed from a social practices perspective. Literacy events in this research have been predicated on the existence of written texts as part of a patient’s journey using health related texts, resources and services. The thesis explores how people go about accessing, understanding, appraising and using health-related services and information, and the social and cultural practices inherent in those activities. It asks how much written patient text is used with patients in hospital; who is using it; what the discourse features of those texts are; and how patients respond to the texts. This mode of exploration is called textual ethnography (Swales, 1998).
The research takes an ethnographic perspective not only on text, but also on participants and their journey. It shadows eleven patients through a cardiology service of a hospital in New Zealand. It identifies literacy events and practices occurring in that space and examines the patient texts themselves using a discourse analysis (Bax 2011; Faircough, 2003; Clerehan, Hirsh, & Buchbinder, 2009; Franken & Hunter, 2011) and geosemiotic (Scollon & Scollon, 2003) approach.
The key themes to emerge from the research centre around the complexity of access to patient information, both physically and linguistically, and around the dynamics of patient agency. The ability to encode and decode written text played a minor part in patient access to information. The analysis showed that the amount and types of text material present for patients in hospital were limited. Access to key texts required a deliberate decision by a health professional to dispense the text items. Mediation of text in the research by literacy sponsors supported Brandt and Clinton’s (2002) observation that “access to literacy has always required assistance, permission, sanction, or coercion by more powerful others or, at least, contact with existing ‘grooves’ of communication” (p. 349). Patient agency therefore came to the fore, and practices that patients did actually use to make information personal to them such as talking with room mates, or requesting paper and pencil were dynamic and socially mediated.
Implications lie in the way health literacy is conceptualised, moving the focus from individual abilities as portrayed in current health literacy definitions, and pointing to the wider role of the health organisation and health care practitioners as literacy sponsors. Practice implications arising from this reconceptualisation relate to patient information strategies within health care organisations and pedagogical implications for health professionals and adult literacy educators. The notions of text mediation and full contextualisation of learning also became apparent with evidence pointing to the effectiveness of text mediation by a more knowing other. The hospital itself was found to be a potentially rich and meaningful setting for adult learning about health where full contextualisation of adult learning is possible. These patient learning opportunities need to be further exploited by health organisations and professionals
Critical conversations: Social workers' perceptions of the use of a closed Facebook group as a participatory professional space.
INTRODUCTION: The rise of social media has been associated with the rapid growth in different forms of digital networking, debate and activism. Many studies have traced the role of social media in mobilising people to take action on shared issues of concern across the world. Yet while networked public spaces offer many possibilities for engagement and interaction, the technology also shapes social dynamics raising questions about privacy, professional boundaries and the nature of online behaviour.
METHOD: The development of a closed professional group on the social networking site Facebook provided an ideal opportunity to explore the perceptions of social workers of their use of participatory public space for professional deliberation and debate about public issues. Members of the group were invited to complete an online survey; eleven social workers accepted invitations to be further interviewed and their subsequent interviews were thematically analysed.
FINDINGS: Social workers involved in the Facebook group benefitted from the resources, research and professional development opportunities afforded to them as members and supported the professional potential and promise of social networking sites. They grappled with what constitutes ethical online behaviour, or netiquette, and identified the limitations and strengths of the social networking group as a place to promote robust professional dialogue and action on social issues.
IMPLICATIONS: Analysis of social worker experience within participatory public spaces offers insight into how the profession can develop modern communication strategies and strong communities of practice in line with its professional principles and mandate
Association of Carotid Plaque Lp-PLA2 with Macrophages and Chlamydia pneumoniae Infection among Patients at Risk for Stroke
BACKGROUND: We previously showed that the burden of Chlamydia pneumoniae in carotid plaques was significantly associated with plaque interleukin (IL)-6, and serum IL-6 and C-reactive protein (CRP), suggesting that infected plaques contribute to systemic inflammatory markers in patients with stroke risk. Since lipoprotein-associated phospholipase A2 (Lp-PLA(2)) mediates inflammation in atherosclerosis, we hypothesized that serum Lp-PLA(2) mass and activity levels and plaque Lp-PLA(2) may be influenced by plaque C. pneumoniae infection. METHODOLOGY/PRINCIPAL FINDINGS: Forty-two patients underwent elective carotid endarterectomy. Tissue obtained at surgery was stained by immunohistochemistry for Lp-PLA(2) grade, macrophages, IL-6, C. pneumoniae and CD4+ and CD8+ cells. Serum Lp-PLA(2) activity and mass were measured using the colorimetric activity method (CAM) and ELISA, respectively. Serum homocysteine levels were measured by HPLC. Eleven (26.2%) patients were symptomatic with transient ischemic attacks. There was no correlation between patient risk factors (smoking, coronary artery disease, elevated cholesterol, diabetes, obesity, hypertension and family history of genetic disorders) for atherosclerosis and serum levels or plaque grade for Lp-PLA(2). Plaque Lp-PLA(2) correlated with serum homocysteine levels (p = 0.013), plaque macrophages (p<0.01), and plaque C. pneumoniae (p<0.001), which predominantly infected macrophages, co-localizing with Lp-PLA(2). CONCLUSIONS: The significant association of plaque Lp-PLA(2) with plaque macrophages and C. pneumoniae suggests an interactive role in accelerating inflammation in atherosclerosis. A possible mechanism for C. pneumoniae in the atherogenic process may involve infection of macrophages that induce Lp-PLA(2) production leading to upregulation of inflammatory mediators in plaque tissue. Additional in vitro and in vivo research will be needed to advance our understanding of specific C. pneumoniae and Lp-PLA(2) interactions in atherosclerosis
Meta-analysis of genome-wide association studies of HDL cholesterol response to statins
BACKGROUND: In addition to lowering low density lipoprotein cholesterol (LDL-C), statin therapy also raises high density lipoprotein cholesterol (HDL-C) levels. Inter-individual variation in HDL-C response to statins may be partially explained by genetic variation.METHODS AND RESULTS: We performed a meta-analysis of genome-wide association studies (GWAS) to identify variants with an effect on statin-induced high density lipoprotein cholesterol (HDL-C) changes. The 123 most promising signals with p<1×10(-4) from the 16 769 statin-treated participants in the first analysis stage were followed up in an independent group of 10 951 statin-treated individuals, providing a total sample size of 27 720 individuals. The only associations of genome-wide significance (p<5×10(-8)) were between minor alleles at the CETP locus and greater HDL-C response to statin treatment.CONCLUSIONS: Based on results from this study that included a relatively large sample size, we suggest that CETP may be the only detectable locus with common genetic variants that influence HDL-C response to statins substantially in individuals of European descent. Although CETP is known to be associated with HDL-C, we provide evidence that this pharmacogenetic effect is independent of its association with baseline HDL-C levels.</p
Pharmacogenetic meta-analysis of genome-wide association studies of LDL cholesterol response to statins
Statins effectively lower LDL cholesterol levels in large studies and the observed interindividual response variability may be partially explained by genetic variation. Here we perform a pharmacogenetic meta-analysis of genome-wide association studies (GWAS) in studies addressing the LDL cholesterol response to statins, including up to 18,596 statin-treated subjects. We validate the most promising signals in a further 22,318 statin recipients and identify two loci, SORT1/CELSR2/PSRC1 and SLCO1B1, not previously identified in GWAS. Moreover, we confirm the previously described associations with APOE and LPA. Our findings advance the understanding of the pharmacogenetic architecture of statin response
IMPACT-Global Hip Fracture Audit: Nosocomial infection, risk prediction and prognostication, minimum reporting standards and global collaborative audit. Lessons from an international multicentre study of 7,090 patients conducted in 14 nations during the COVID-19 pandemic
New genetic loci link adipose and insulin biology to body fat distribution.
Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
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