661 research outputs found

    Intelligibility of average talkers in typical listening environments,”

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    Intelligibility of conversationally produced speech for normal hearing listeners was studied for three male and three female talkers. Four typical listening environments were used. These simulated a quiet living room, a classroom, and social events in two settings with different reverberation characteristics. For each talker, overall intelligibility and intelligibility for vowels, consonant voicing, consonant continuance, and consonant place were quantified using the speech pattern contrast (SPAC) test. Results indicated that significant intelligibility differences are observed among normal talkers even in listening environments that permit essentially full intelligibility for everyday conversations. On the whole, talkers maintained their relative intelligibility across the four environments, although there was one exception which suggested that some voices may be particularly susceptible to degradation due to reverberation. Consonant place was the most poorly perceived feature, followed by continuance, voicing, and vowel intelligibility. However, there were numerous significant interactions between talkers and speech features, indicating that a talker of average overall intelligibility may produce certain speech features with intelligibility that is considerably higher or lower than average. Neither long-term rms speech spectrum nor articulation rate was found to be an adequate single criterion for selecting a talker of average intelligibility. Ultimately, an average talker was chosen on the basis of four speech contrasts: initial consonant place, and final consonant place, voicing, and continuance. and Taken together, these reports lead to the conclusion that when a speech intelligibility test is used to determine either (a) which of several hearing aids provides the most improvement in speech understanding, or (b) the absolute amount of improvement provided bY a particular instrument, the outcome will depend partly on the characteristics of the talker used to record the test materials and on the manner in which the materials are generated (conversational or clear). It is perhaps surprising that relatively little investigative attention has been paid to the issues involved in selection of talkers for speech intelligibility tests. When a new intelligibility test is reported, the talker is typically described as lacking a pronounced regional accent: There are no other criteria commonly applied in talker selection. However, if the test results are used to predict heating aid benefit for understanding everyday speech, it would appear, from the studies cited above, that care Should be taken to assure that the talker's speech is average in intelligibility and that the speech itself is delivered in a conversational/ normal manner when the test materials are recorded. A review of the literature failed to reveal any investigations that provided analytic data describing the intelligibility, for normal heating listeners, of normal talkers producing conversational speech in everyday listening settings. Hence, the present study was undertaken in an attempt to generate these data. The ultimate purpose in developing a description of the intelligibility of normal talkers was to provide a basis for selecting a talker of average intelligibility. In future work the chosen talker will produce speech materials for a speech intelligibility test to be used to quantify hearing aid benefit. Each talker's long-term rms 1/3-oct-band speech spectrum is shown in The SPAC test words were embedded in the sentences shown in Appendix A. These sentences were devised to present the items in a variety of contexts (as occurs in everday speech) with respect to preceding and following phonemes, position of test item in the utterance, and length of utterance. For each subtest, the 12 sentences were randomly assigned to the 12 test items. Each form (consisting of four subtests) was preceded by four practice items. Sentences for the practice items are also given in Appendix A. L Production of master recordings There For this talker combination, EH was rerecorded in environment A, FH was used in environment B, GF was used in environment C1, and EF was used in environment C2. Different combinations of two forms were used in the reduced intelligibility conditions, described below; all forms were used an equal number of times overall. The recordings of the six talkers were presented at an equal integrated rms level. To adjust the SPAC items appropriately for each environment, the recording for talker • 1 was adjusted to achieve the primary message level (in dB L• ) for that environment. The remaining talkers were presented at the same overall level as talker # 1. Hence, the spectra shown in The two SPAC forms recorded for each talker in each basic listening environment will be referred to as "typical intelligibility" conditions because they were adjusted to S/B ratio values that are maintained by normal talkers and listeners to yield essentially full intelligibility for conversations in these environments (according to the data of Pearsons etal., 1977). In addition, the remaining two SPAC forms for each talker were recorded in the same settings but with the background noise level increased sufficiently to reduce all contrast scores to less than 100%. The amount of increase in background noise necessary to achieve this differed across the four environments and was selected empirically in eac

    Hearing Aid Patients in Private Practice and Public Health (Veterans Affairs) Clinics: Are They Different?

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    Objective: In hearing aid research, it is commonplace to combine data across subjects whose hearing aids were provided in different service delivery models. There is reason to question whether these types of patients are always similar enough to justify this practice. To explore this matter, this investigation evaluated similarities and differences in self-report data obtained from hearing aid patients derived from public health (Veterans Affairs, VA) and private practice (PP) settings. Design: The study was a multisite, cross-sectional survey in which 230 hearing aid patients from VA and PP audiology clinic settings provided self-report data on a collection of questionnaires both before and after the hearing aid fitting. Subjects were all older adults with mild to moderately severe hearing loss. About half of them had previous experience wearing hearing aids. All subjects were fitted with wide-dynamic-range-compression instruments and received similar treatment protocols. Results: Numerous statistically significant differences were observed between the VA and PP subject groups. Before the fitting, VA patients reported higher expectations from the hearing aids and more severe unaided problems compared with PP patients with similar audiograms. Three wks after the fitting, VA patients reported more satisfaction with their hearing aids. On some measures VA patients reported more benefit, but different measures of benefit did not give completely consistent results. Both groups reported using the hearing aids an average of approximately 8 hrs per day. VA patients reported age-normal physical and mental health, but PP patients tended to report better than typical health for their age group. Conclusions: These data indicate that hearing aid patients seen in the VA public health hearing services are systematically different in self-report domains from those seen in private practice services. It is therefore risky to casually combine data from these two types of subjects or to generalize research results from one group to the other. Further, compared with PP patients, VA patients consistently reported more favorable hearing aid fitting outcomes. Additional study is indicated to explore the determinants of this result and its generalizability to other public health service delivery systems such as those in other countries. Moreover, efforts should be made to assess the potential for transferring positive elements from the VA system to the PP service delivery system, if possible. (Ear & Hearing 2005;26;513-528) It is arguable that audiology in the United States had its origins in the programs designed to provide rehabilitation for veterans who had sustained hearing damage as a result of military service in World War II. One of the major components of those programs was provision of amplification and counseling about its use. Since that time, the Department of Veterans Affairs (VA) has been a major supporter of research oriented toward the acquisition of scientific and clinical knowledge about provision of hearing aids for adults. A large volume of literature has accumulated describing the results of experiments that have featured hearing-impaired veterans as subjects. These patients receive services in a public health system in which public funds are used to provide services to improve or protect the health of veterans. At least two other entities have supported and produced research exploring hearing aids and fitting methods: hearing aid manufacturers and academic institutions such as universities and the National Institutes of Health. Many of the subjects serving in these studies were recruited from sources that would not be classified as public health services, such as free-standing dispensing practices or university-based dispensing clinics. In this article, patients seen in free-standing dispensing practices are classified as receiving services in a private practice (PP) system. University-based clinics might differ from freestanding dispensaries along several dimensions. a Some university-based clinics operate in a way that is similar to a private practice, whereas others do not follow this model. The VA public health service delivery setting is different in several key respects from most PP service delivery settings. The VA clinic is usually lo

    Development of APHAB norms of WDRC hearing aids and comparisons with original norms.

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    Objectives: This study was undertaken for two purposes: First, to provide a comparison of subjective performance and benefit measured with the Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaire for two groups. One group included hearing-impaired individuals using 1990s-era linear processing hearing aids. The other group included hearing-impaired individuals using more current wide-dynamic range compression (WDRC)-capable hearing aids fit using current practice protocols. The second purpose of this study was to determine whether APHAB norms derived from scores for current hearing aid users were different from the original 1995 norms. It was hypothesized that technology improvements would result in improved subjective performance for modern hearing aid wearers. Design: A systematic sampling method was used to identify and recruit subjects from seven private-practice audiology clinics located across the United States. Potential subjects were limited to older hearingimpaired individuals who were wearing hearing aids capable of WDRC processing. One hundred fifty-four subjects returned completed APHAB questionnaires. Participants reported mostly moderate to moderately severe subjective hearing difficulty. Results: No differences in perceived difficulty with speech communication were observed between the two groups. However, aversiveness of amplified sound was less frequently reported for users of WDRCcapable hearing aids. Norms were generated using data from all of the operationally defined successful hearing aid users in the sample and compared with the original 1995 norms. Differences between the 1995 and 2005 norms were minimal for the speech communication subscales. However, the 2005 group consistently reported less frequent difficulties with sound aversiveness (AV subscale) in the aided condition. In addition to these findings, an improvement was observed in the rate of successful adjustment to hearing aids between 1995 (43%) and 2005 (82%). Conclusions: Overall, problems understanding amplified speech did not decrease in frequency when hearing aids transitioned from linear to compression processing; however, the compression capabilities of current hearing aids (with a possible contribution from noise reduction algorithms) have resulted in less negative reactions to amplified environmental sounds. This suggests that modern technology has ameliorated (to some extent) the common complaint that hearing aids cause many everyday sounds to become objectionably loud. Although the results of this study suggest that the advantages of improved technology do not lie in the domains of improved subjective speech communication performance, substantial improvement in the rate of successful adjustment to hearing aids between the 1995 and 2005 subject groups provides evidence that modern hearing aid technology has produced progress in other outcome domains

    Monitoring the health of the greater Mekong’s rivers

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    The methods used for biomonitoring can be sophisticated, producing highly accurate results, but can also be simplified for communities to use. In countries where budgets for biomonitoring are low, using community-based biomonitoring systems can effectively and cheaply tell us about a river’s health

    A Survey of Honey Bee Colony Losses in the U.S., Fall 2007 to Spring 2008

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    Honey bees are an essential component of modern agriculture. A recently recognized ailment, Colony Collapse Disorder (CCD), devastates colonies, leaving hives with a complete lack of bees, dead or alive. Up to now, estimates of honey bee population decline have not included losses occurring during the wintering period, thus underestimating actual colony mortality. Our survey quantifies the extent of colony losses in the United States over the winter of 2007–2008.Surveys were conducted to quantify and identify management factors (e.g. operation size, hive migration) that contribute to high colony losses in general and CCD symptoms in particular. Over 19% of the country's estimated 2.44 million colonies were surveyed. A total loss of 35.8% of colonies was recorded; an increase of 11.4% compared to last year. Operations that pollinated almonds lost, on average, the same number of colonies as those that did not. The 37.9% of operations that reported having at least some of their colonies die with a complete lack of bees had a total loss of 40.8% of colonies compared to the 17.1% loss reported by beekeepers without this symptom. Large operations were more likely to have this symptom suggesting that a contagious condition may be a causal factor. Sixty percent of all colonies that were reported dead in this survey died without dead bees, and thus possibly suffered from CCD. In PA, losses varied with region, indicating that ambient temperature over winter may be an important factor.Of utmost importance to understanding the recent losses and CCD is keeping track of losses over time and on a large geographic scale. Given that our surveys are representative of the losses across all beekeeping operations, between 0.75 and 1.00 million honey bee colonies are estimated to have died in the United States over the winter of 2007–2008. This article is an extensive survey of U.S. beekeepers across the continent, serving as a reference for comparison with future losses as well as providing guidance to future hypothesis-driven research on the causes of colony mortality

    Social Preferences and the Efficiency of Bilateral Exchange

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    Under what conditions do social preferences, such as altruism or a concern for fair outcomes, generate efficient trade? I analyze theoretically a simple bilateral exchange game: Each player sequentially takes an action that reduces his own material payoff but increases the other player’s. Each player’s preferences may depend on both his/her own material payoff and the other player’s. I identify necessary conditions and sufficient conditions on the players’ preferences for the outcome of their interaction to be Pareto efficient. The results have implications for interpreting the rotten kid theorem, gift exchange in the laboratory, and gift exchange in the field

    Epithelial-Associated Inflammatory Pathways Underlie Residual Asthma Exacerbations in Urban Children Treated with Mepolizumab Therapy

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    Rationale: Identification of airway inflammatory pathways in asthma has proven essential to understanding mechanisms of disease and has led to effective personalized treatment with biologic therapies. However, relatively little is known about patterns of airway inflammation at the time of respiratory illnesses and how such patterns relate to responsiveness to biologic therapies. Methods: The MUPPITS-1 (n=106) and MUPPITS-2 (n=290) studies investigated asthma exacerbations in urban children with exacerbation-prone asthma and ≥150/microliter blood eosinophils. Children in both studies received guidelines-based asthma care; in MUPPITS-2, participants were additionally randomized (1:1) to placebo or mepolizumab. Nasal lavage samples were collected during respiratory illnesses for RNA-sequencing and analyzed by modular analysis to assess genome-wide expression patterns associated with exacerbation illnesses. Results: Among 284 illnesses, exacerbations that occurred in the absence of mepolizumab therapy showed significantly higher upregulation of eosinophil associated inflammatory pathways (fold change values [FC]=1.27-1.43, p-values\u3c0.05), including a Type-2 inflammation module composed of eosinophil, mast cell, and IL-13 response genes. In contrast, exacerbations that occurred while on mepolizumab therapy showed significantly higher upregulation of several epithelial inflammatory pathways (FC=1.36-1.64, p-values\u3c0.05) including TGF-β/Smad3 signaling, extracellular matrix production, and epidermal growth factor receptor signaling. Conclusions: These results indicate that novel inflammatory pathways, likely originating from the airway epithelium and distinct from Type-2 or eosinophilic inflammation, drive residual exacerbations that occur in children treated with mepolizumab therapy added to guideline-based care. These findings identify likely mechanisms of persistent disease expression in these children despite significant depletion of eosinophils and can identify novel treatment targets for future studies

    Mepolizumab Alters Regulation of Airway Type-2 Inflammation in Urban Children with Asthma by Disrupting Eosinophil Gene Expression but Enhancing Mast Cell and Epithelial Pathways

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    Rationale: Mepolizumab (anti-IL5) reduces asthma exacerbations in urban children. We previously utilized nasal transcriptomics to identify inflammatory pathways (gene co-expression modules) associated with exacerbations despite this therapy. To understand mepolizumab’s precise impact on these pathways, we assess gene co-expression and loss of correlation, “decoherence,” using differential co-expression network analyses. Methods: 290 urban children (6-17 years) with exacerbation-prone asthma and blood eosinophils ≥150/microliter were randomized (1:1) to q4 week placebo or mepolizumab injections added to guideline-based care for 52 weeks. Nasal lavage samples were collected before and during treatment for RNA-sequencing. Differential co-expression of gene networks was evaluated to assess interactions and regulatory aspects of type-2 and eosinophilic airway inflammation. Results: Mepolizumab, but not placebo, significantly reduced the overall expression of an established type-2 inflammation gene co-expression module (fold change=0.77, p=0.002) enriched for eosinophil, mast cell, and epithelial IL-13 response genes (242 genes). Mepolizumab uncoupled co-expression of genes in this pathway. During mepolizumab, but not placebo treatment, there was significant loss of correlation among eosinophil-specific genes including RNASE2 (EDN), RNASE3 (ECP), CLC, SIGLEC8, and IL5RA contrasting a reciprocal increase in correlation among mast cell-specific genes (TPSAB1, CPA3, FCER1A), T2 cytokines (IL4, IL5, and IL13), and POSTN. Conclusions: These results suggest mepolizumab disrupts the regulatory interactions of gene co-expression among airway eosinophils, mast cells and epithelium by interrupting transcription regulation in eosinophils with enhancement in mast cell and epithelial inflammation. This paradoxical effect may contribute to an incomplete reduction of asthma exacerbations and demonstrates how differential co-expression network analyses can identify targets for more precise therapies

    Assessing the accuracy of an inter-institutional automated patient-specific health problem list

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    <p>Abstract</p> <p>Background</p> <p>Health problem lists are a key component of electronic health records and are instrumental in the development of decision-support systems that encourage best practices and optimal patient safety. Most health problem lists require initial clinical information to be entered manually and few integrate information across care providers and institutions. This study assesses the accuracy of a novel approach to create an inter-institutional automated health problem list in a computerized medical record (MOXXI) that integrates three sources of information for an individual patient: diagnostic codes from medical services claims from all treating physicians, therapeutic indications from electronic prescriptions, and single-indication drugs.</p> <p>Methods</p> <p>Data for this study were obtained from 121 general practitioners and all medical services provided for 22,248 of their patients. At the opening of a patient's file, all health problems detected through medical service utilization or single-indication drug use were flagged to the physician in the MOXXI system. Each new arising health problem were presented as 'potential' and physicians were prompted to specify if the health problem was valid (Y) or not (N) or if they preferred to reassess its validity at a later time.</p> <p>Results</p> <p>A total of 263,527 health problems, representing 891 unique problems, were identified for the group of 22,248 patients. Medical services claims contributed to the majority of problems identified (77%), followed by therapeutic indications from electronic prescriptions (14%), and single-indication drugs (9%). Physicians actively chose to assess 41.7% (n = 106,950) of health problems. Overall, 73% of the problems assessed were considered valid; 42% originated from medical service diagnostic codes, 11% from single indication drugs, and 47% from prescription indications. Twelve percent of problems identified through other treating physicians were considered valid compared to 28% identified through study physician claims.</p> <p>Conclusion</p> <p>Automation of an inter-institutional problem list added over half of all validated problems to the health problem list of which 12% were generated by conditions treated by other physicians. Automating the integration of existing information sources provides timely access to accurate and relevant health problem information. It may also accelerate the uptake and use of electronic medical record systems.</p

    The Cues and Care Trial: A randomized controlled trial of an intervention to reduce maternal anxiety and improve developmental outcomes in very low birthweight infants

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    Abstract Background Very low birthweight infants are at risk for deficits in cognitive and language development, as well as attention and behaviour problems. Maternal sensitive behaviour (i.e. awareness of infant cues and appropriate responsiveness to those cues) in interaction with her very low birthweight infant is associated with better outcomes in these domains; however, maternal anxiety interferes with the mother's ability to interact sensitively with her very low birthweight infant. There is a need for brief, cost-effective and timely interventions that address both maternal psychological distress and interactive behaviour. The Cues and Care trial is a randomized controlled trial of an intervention designed to reduce maternal anxiety and promote sensitive interaction in mothers of very low birthweight infants. Methods and design Mothers of singleton infants born at weights below 1500 g are recruited in the neonatal intensive care units of 2 tertiary care hospitals, and are randomly assigned to the experimental (Cues) intervention or to an attention control (Care) condition. The Cues intervention teaches mothers to attend to their own physiological, cognitive, and emotional cues that signal anxiety and worry, and to use cognitive-behavioural strategies to reduce distress. Mothers are also taught to understand infant cues and to respond sensitively to those cues. Mothers in the Care group receive general information about infant care. Both groups have 6 contacts with a trained intervener; 5 of the 6 sessions take place during the infant's hospitalization, and the sixth contact occurs after discharge, in the participant mother's home. The primary outcome is maternal symptoms of anxiety, assessed via self-report questionnaire immediately post-intervention. Secondary outcomes include maternal sensitive behaviour, maternal symptoms of posttraumatic stress, and infant development at 6 months corrected age. Discussion The Cues and Care trial will provide important information on the efficacy of a brief, skills-based intervention to reduce anxiety and increase sensitivity in mothers of very low birthweight infants. A brief intervention of this nature may be more readily implemented as part of standard neonatal intensive care than broad-based, multi-component interventions. By intervening early, we aim to optimize developmental outcomes in these high risk infants. Trial Registration Current Controlled Trials ISRCTN00918472 The Cues and Care Trial: A randomized controlled trial of an intervention to reduce maternal anxiety and improve developmental outcomes in very low birthweight infant
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