Perceptual weighting of acoustic cues for accommodating gender-related talker differences heard by listeners with normal hearing and with cochlear implants.

Listeners must accommodate acoustic differences between vocal tracts and speaking styles of conversation partners-a process called normalization or accommodation. This study explores what acoustic cues are used to make this perceptual adjustment by listeners with normal hearing or with cochlear implants, when the acoustic variability is related to the talker's gender. A continuum between /ʃ/ and /s/ was paired with naturally spoken vocalic contexts that were parametrically manipulated to vary by numerous cues for talker gender including fundamental frequency (F0), vocal tract length (formant spacing), and direct spectral contrast with the fricative. The goal was to examine relative contributions of these cues toward the tendency to have a lower-frequency acoustic boundary for fricatives spoken by men (found in numerous previous studies). Normal hearing listeners relied primarily on formant spacing and much less on F0. The CI listeners were individually variable, with the F0 cue emerging as the strongest cue on average.

Patterns of conservation of spliceosomal intron structures and spliceosome divergence in representatives of the diplomonad and parabasalid lineages.

BACKGROUND: Two spliceosomal intron types co-exist in eukaryotic precursor mRNAs and are excised by distinct U2-dependent and U12-dependent spliceosomes. In the diplomonad Giardia lamblia, small nuclear (sn) RNAs show hybrid characteristics of U2- and U12-dependent spliceosomal snRNAs and 5 of 11 identified remaining spliceosomal introns are trans-spliced. It is unknown whether unusual intron and spliceosome features are conserved in other diplomonads. RESULTS: We have identified spliceosomal introns, snRNAs and proteins from two additional diplomonads for which genome information is currently available, Spironucleus vortens and Spironucleus salmonicida, as well as relatives, including 6 verified cis-spliceosomal introns in S. vortens. Intron splicing signals are mostly conserved between the Spironucleus species and G. lamblia. Similar to 'long' G. lamblia introns, RNA secondary structural potential is evident for 'long' (> 50 nt) Spironucleus introns as well as introns identified in the parabasalid Trichomonas vaginalis. Base pairing within these introns is predicted to constrain spatial distances between splice junctions to similar distances seen in the shorter and uniformly-sized introns in these organisms. We find that several remaining Spironucleus spliceosomal introns are ancient. We identified a candidate U2 snRNA from S. vortens, and U2 and U5 snRNAs in S. salmonicida; cumulatively, illustrating significant snRNA differences within some diplomonads. Finally, we studied spliceosomal protein complements and find protein sets in Giardia, Spironucleus and Trepomonas sp. PC1 highly- reduced but well conserved across the clade, with between 44 and 62 out of 174 studied spliceosomal proteins detectable. Comparison with more distant relatives revealed a highly nested pattern, with the more intron-rich fornicate Kipferlia bialata retaining 87 total proteins including nearly all those observed in the diplomonad representatives, and the oxymonad Monocercomonoides retaining 115 total proteins including nearly all those observed in K. bialata. CONCLUSIONS: Comparisons in diplomonad representatives and species of other closely-related metamonad groups indicates similar patterns of intron structural conservation and spliceosomal protein composition but significant divergence of snRNA structure in genomically-reduced species. Relative to other eukaryotes, loss of evolutionarily-conserved snRNA domains and common sets of spliceosomal proteins point to a more streamlined splicing mechanism, where intron sequences and structures may be functionally compensating for the minimalization of spliceosome components.

Pupillometry Reveals That Context Benefit in Speech Perception Can Be Disrupted by Later-Occurring Sounds, Especially in Listeners With Cochlear Implants.

Contextual cues can be used to improve speech recognition, especially for people with hearing impairment. However, previous work has suggested that when the auditory signal is degraded, context might be used more slowly than when the signal is clear. This potentially puts the hearing-impaired listener in a dilemma of continuing to process the last sentence when the next sentence has already begun. This study measured the time course of the benefit of context using pupillary responses to high- and low-context sentences that were followed by silence or various auditory distractors (babble noise, ignored digits, or attended digits). Participants were listeners with cochlear implants or normal hearing using a 12-channel noise vocoder. Context-related differences in pupil dilation were greater for normal hearing than for cochlear implant listeners, even when scaled for differences in pupil reactivity. The benefit of context was systematically reduced for both groups by the presence of the later-occurring sounds, including virtually complete negation when sentences were followed by another attended utterance. These results challenge how we interpret the benefit of context in experiments that present just one utterance at a time. If a listener uses context to "repair" part of a sentence, and later-occurring auditory stimuli interfere with that repair process, the benefit of context might not survive outside the idealized laboratory or clinical environment. Elevated listening effort in hearing-impaired listeners might therefore result not just from poor auditory encoding but also inefficient use of context and prolonged processing of misperceived utterances competing with perception of incoming speech.

RNA-Seq employing a novel rRNA depletion strategy reveals a rich repertoire of snoRNAs in Euglena gracilis including box C/D and Ψ-guide RNAs targeting the modification of rRNA extremities.

Previous mRNA transcriptome studies of Euglena gracilis have shown that this organism possesses a large and diverse complement of protein coding genes; however, the study of non-coding RNA classes has been limited. The natural extensive fragmentation of the E. gracilis large subunit ribosomal RNA presents additional barriers to the identification of non-coding RNAs as size-selected small RNA libraries will be dominated by rRNA sequences. In this study we have developed a strategy to significantly reduce rRNA amplification prior to RNA-Seq analysis thereby producing a ncRNA library allowing for the identification of many new E. gracilis small RNAs. Library analysis reveals 113 unique new small nucleolar (sno) RNAs and a large collection of snoRNA isoforms, as well as the first significant collection of nuclear tRNAs in this organism. A 3' end AGAUGN consensus motif and conserved structural features can now be defined for E. gracilis pseudouridine guide RNAs. snoRNAs of both classes were identified that target modification of the 3' extremities of rRNAs utilizing predicted base-pairing interactions with internally transcribed spacers (ITS), providing insight into the timing of steps in rRNA maturation. Cumulatively, this represents the most comprehensive analysis of small ncRNAs in Euglena gracilis to date.

Acceptance of internet-based hearing healthcare among adults who fail a hearing screening.

OBJECTIVE: This study measured help-seeking readiness and acceptance of existing internet-based hearing healthcare (IHHC) websites among a group of older adults who failed a hearing screening (Phase 1). It also explored the effects of brief training on participants' acceptance of IHHC (Phase 2). STUDY SAMPLE: Twenty-seven adults (age 55+) who failed a hearing screening participated. DESIGN: During Phase 1 participants were administered the University of Rhode Island Change Assessment (URICA) and patient technology acceptance model (PTAM) Questionnaire. During Phase 2 participants were randomly assigned to a training or control group. Training group participants attended an instructional class on existing IHHC websites. The control group received no training. The PTAM questionnaire was re-administered to both groups 4-6 weeks following the initial assessment. RESULTS: The majority of participants were either considering or preparing to do something about their hearing loss, and were generally accepting of IHHC websites (Phase 1). The participants who underwent brief IHHC training reported increases in hearing healthcare knowledge and slight improvements in computer self-efficacy (Phase 2). CONCLUSIONS: Older adults who fail hearing screenings may be good candidates for IHHC. The incorporation of a simple user-interface and short-term training may optimize the usability of future IHHC programs for this population.

The Effect of Chronological Age on the Acceptance of Internet-Based Hearing Health Care.

PURPOSE: The purpose of this article is to offer design considerations in developing Internet-based hearing health care for older adults by analyzing and discussing the relationship between chronological age, computer skills, and the acceptance of Internet-based hearing health care. METHOD: This article reports baseline data from a training study measuring the acceptance of Internet-based hearing health care. Participants (n = 26; 20 men, 6 women) were aged 55­95 years. All passed a cognitive screen and failed a hearing screen. Participants completed the Patient- Technology Acceptance questionnaire (Or, 2008). Computer literacy was measured using the Northstar Digital Literacy Assessment (Cytron-Hysom, Hadley, Vanek, Graif, & Asp, 2012). RESULTS: Computer literacy was negatively correlated with increasing age. Additional negative relationships were seen between computer literacy and computer anxiety and between computer literacy and computer self-efficacy. Finally, there was a negative relationship between computer self-efficacy and computer anxiety. CONCLUSION: These results suggest computer literacy is lower in adults of advanced age than in those who are a few years younger. Indirect relationships were observed between age and computer self-efficacy and between age and computer anxiety. Consideration should be given to addressing discrepancies in self-efficacy and computer literacy in older adults to increase the likelihood of acceptance of Internet-based hearing health care.

Evolutionarily divergent spliceosomal snRNAs and a conserved non-coding RNA processing motif in Giardia lamblia.

Non-coding RNAs (ncRNAs) have diverse essential biological functions in all organisms, and in eukaryotes, two such classes of ncRNAs are the small nucleolar (sno) and small nuclear (sn) RNAs. In this study, we have identified and characterized a collection of sno and snRNAs in Giardia lamblia, by exploiting our discovery of a conserved 12 nt RNA processing sequence motif found in the 3' end regions of a large number of G. lamblia ncRNA genes. RNA end mapping and other experiments indicate the motif serves to mediate ncRNA 3' end formation from mono- and di-cistronic RNA precursor transcripts. Remarkably, we find the motif is also utilized in the processing pathway of all four previously identified trans-spliced G. lamblia introns, revealing a common RNA processing pathway for ncRNAs and trans-spliced introns in this organism. Motif sequence conservation then allowed for the bioinformatic and experimental identification of additional G. lamblia ncRNAs, including new U1 and U6 spliceosomal snRNA candidates. The U6 snRNA candidate was then used as a tool to identity novel U2 and U4 snRNAs, based on predicted phylogenetically conserved snRNA-snRNA base-pairing interactions, from a set of previously identified G. lamblia ncRNAs without assigned function. The Giardia snRNAs retain the core features of spliceosomal snRNAs but are sufficiently evolutionarily divergent to explain the difficulties in their identification. Most intriguingly, all of these snRNAs show structural features diagnostic of U2-dependent/major and U12-dependent/minor spliceosomal snRNAs.

Clustered organization, polycistronic transcription, and evolution of modification-guide snoRNA genes in Euglena gracilis.

Previous studies have shown that the eukaryotic microbe Euglena gracilis contains an unusually large assortment of small nucleolar RNAs (snoRNAs) and ribosomal RNA (rRNA) modification sites. However, little is known about the evolutionary mechanisms contributing to this situation. In this study, we have examined the organization and evolution of snoRNA genes in Euglena with the additional objective of determining how these properties relate to the rRNA modification pattern in this protist. We have identified and extensively characterized a clustered pattern of genes encoding previously biochemically isolated snoRNA sequences in E. gracilis. We show that polycistronic transcription is a prevalent snoRNA gene expression strategy in this organism. Further, we have identified 121 new snoRNA coding regions through sequence analysis of these clusters. We have identified an E. gracilis U14 snoRNA homolog clustered with modification-guide snoRNA genes. The U14 snoRNAs in other eukaryotic organisms examined to date typically contain both a modification and a processing domain. E. gracilis U14 lacks the modification domain but retains the processing domain. Our analysis of U14 structure and evolution in Euglena and other eukaryotes allows us to propose a model for its evolution and suggest its processing role may be its more important function, explaining its conservation in many eukaryotes. The preponderance of apparent small and larger-scale duplication events in the genomic regions we have characterized in Euglena provides a mechanism for the generation of the unusually diverse collection and abundance of snoRNAs and modified rRNA sites. Our findings provide the framework for more extensive whole genome analysis to elucidate whether these snoRNA gene clusters are spread across multiple chromosomes and/or form dense "arrays" at a limited number of chromosomal loci.

Effect of competitiveness on forty-yard dash performance in college men and women.

The objective of this study was to determine performance differences between individual and competitive trials of the 40-yard dash. Physically active college men (n = 25) and women (n = 29) performed an individual 40-yard dash, followed by completion of the Sports Competition Trait Inventory (SCTI) before performing a paired 40-yard dash against a time-matched competitor. All sprints were performed on an indoor rubberized track using photoelectric gates to start and stop a digital timer. In addition, 3 timers used hand-held stopwatches to record the individual sprint time. There was no significant difference (p = 0.10) between men (120.3 +/- 16.6) and women (111.7 +/- 20.3) on the SCTI. There was no significant difference between individual and competitive 40-yard dash times for either men (5.21 +/- 0.24 and 5.19 +/- 0.23 seconds, respectively) or women (6.12 +/- 0.31 and 6.11 +/- 0.32 seconds, respectively). The correlation between SCTI and both individual and competitive 40-yard dashes was significant (p < 0.05) for women (r = -0.45 and -0.44, respectively) but not for men (r = -0.10 and 0.10, respectively). Electronic times (5.70 +/- 0.54 seconds) were not significantly different from 1 hand-timer (5.71 +/- 0.56 seconds) but were significantly faster than the other 2 timers (5.80 +/- 0.58 and 5.82 +/- 0.57 seconds). Averaging the 3 hand times (5.78 +/- 0.56 seconds) for comparison with the electronic timing (5.70 +/- 0.54 seconds) produced a high correlation (r = 0.96) but a significantly slower time (p < 0.05). A competitive environment does not appear to improve short sprint times in either men or women. In addition, hand timing may not always produce faster times compared to electronic timing.