Systematic Comparison of Trial Exclusion Criteria for Pupillometry Data Analysis in Individuals With Single-Sided Deafness and Normal Hearing

The measurement of pupil dilation has become a common way to assess listening effort. Pupillometry data are subject to artifacts, requiring highly contaminated data to be discarded from analysis. It is unknown how trial exclusion criteria impact experimental results. The present study examined the effect of a common exclusion criterion, percentage of blinks, on speech intelligibility and pupil dilation measures in 9 participants with single-sided deafness (SSD) and 20 participants with normal hearing. Participants listened to and repeated sentences in quiet or with speech maskers. Pupillometry trials were processed using three levels of blink exclusion criteria: 15%, 30%, and 45%. These percentages reflect a threshold for missing data points in a trial, where trials that exceed the threshold are excluded from analysis. Results indicated that pupil dilation was significantly greater and intelligibility was significantly lower in the masker compared with the quiet condition for both groups. Across-group comparisons revealed that speech intelligibility in the SSD group decreased significantly more than the normal hearing group from quiet to masker conditions, but the change in pupil dilation was similar for both groups. There was no effect of blink criteria on speech intelligibility or pupil dilation results for either group. However, the total percentage of blinks in the masker condition was significantly greater than in the quiet condition for the SSD group, which is consistent with previous studies that have found a relationship between blinking and task difficulty. This association should be carefully considered in future experiments using pupillometry to gauge listening effort.

Empirical models of Total Electron Content based on functional fitting over Taiwan during geomagnetic quiet condition

Empirical models of Total Electron Content (TEC) based on functional fitting over Taiwan (120° E, 24° N) have been constructed using data of the Global Positioning System (GPS) from 1998 to 2007 during geomagnetically quiet condition (Dst>−30 nT). The models provide TEC as functions of local time (LT), day of year (DOY) and the solar activity (F), which are represented by 1–162 days mean of F10.7 and EUV. Other models based on median values have been also constructed and compared with the models based on the functional fitting. Under same values of F parameter, the models based on the functional fitting show better accuracy than those based on the median values in all cases. The functional fitting model using daily EUV is the most accurate with 9.2 TECu of root mean square error (RMS) than the 15-days running median with 10.4 TECu RMS and the model of International Reference Ionosphere 2007 (IRI2007) with 14.7 TECu RMS. IRI2007 overestimates TEC when the solar activity is low, and underestimates TEC when the solar activity is high. Though average of 81 days centered running mean of F10.7 and daily F10.7 is often used as indicator of EUV, our result suggests that average of F10.7 mean from 1 to 54 day prior and current day is better than the average of 81 days centered running mean for reproduction of TEC. This paper is for the first time comparing the median based model with the functional fitting model. Results indicate the functional fitting model yielding a better performance than the median based one. Meanwhile we find that the EUV radiation is essential to derive an optimal TEC.

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We have received your counsell's letter, and the counsell heare are very sensible of your condition and will not want desires and endevors to get you monyes. The assignments allready orderd you will, I presume, not make your arreare so great as a 100,000. We shall compare your account sent to collonel Jones with what the treasurers heare comput it at, and if you are not equally concerned and provided for with any of the other forces we shall soone remidy that difficulty, though the complaints from Scotland and the army in England are much to the same purpose, and really our case is so sadde that which way we shall be able to turn ourselves from the difficultyes we are under I know not; but I shall no more at presant trouble you and shall by the next have an exact account, and in the meane time we shall charge the 20,000 formerly assigned out of delinquents' lands upon the new buildings.1 Our fleet and armyes are in a sadde condition. This army never hade such an occation to be tempted as they have now, yet are, and I trust will be, in a very stauch2 and quiet condition. The Lord direct and manage the hearts of the parliment to such a consideration of the case of this nation that the issue may be for further settlement of thes poore nations, upon true and lasting foundations in preserving the libertyes of the people of God, and the civill libertyes allso, both of which we ought to have a due regard unto, though the 1st to have the preference. I think ther is much in the present goverment which conserves both, which that it may be most upon our hearts is the desire of,

Quiet-condition variations in the scale height at F2-layer peak at Jicamarca during solar minimum and maximum

This study is the first attempt to examine the quiet-condition variations in scale height (Hm) near the F2-layer peak in the equatorial ionosphere. The data periods of Hm derived from the Jicamarca ionograms are January-December 1996 and April 1999–March 2000. The results show that the greatest and smallest Hm values are generally at 11:00–12:00 LT and 04:00–05:00 LT, respectively. Additionally, the sunrise peak occurs at 06:00 LT only during solar minimum. The post-sunset peaks in the equinoctial and summer months are more obvious during solar maximum. The Hm difference between solar minimum and maximum are significant from afternoon to midnight. On the other hand, the Hm values during 07:00–10:00 LT for solar minimum are close to those for solar maximum. Furthermore, the correlation of Hm with the critical frequency (foF2) of F2-layer is generally low. In contrast, the correlation between Hm and the peak height (hmF2) of F2-layer is high. For Hm and the thickness parameter (B0) of F2-layer, the correlation between these two parameters is almost perfect.

Prosodic differences in mothers' speech to toddlers in quiet and noisy environments

We examined mothers' speech to 2-year-old children in both quiet and moderately noisy conditions. Mothers were recorded while teaching their children two words, one of which occurred in the context of other people speaking. Parents used characteristics of infant-directed speech (IDS) to these older children. Even more interesting was that many of the prosodic changes typical in IDS were accentuated in noise. In a context in which multiple people were speaking simultaneously, mothers spoke to their children with both increased pitch and increased word duration relative to when they spoke in a quiet condition. However, these changes were quite small, lending only mixed support to proposals that one of the advantages of IDS is that it is easier to separate from background noise.

HINT List Equivalency Using Older Listeners

HINT list equivalency was examined using 24 listeners between 60 and 70 years old who had sensorineural hearing impairment. A Greco-Latin square design was used to ensure that each list was presented an equal number of times per condition. Four conditions were tested: (1) speech in quiet, (2) speech in 65 dBA noise with noise at 0° azimuth, (3) speech in 65 dBA noise with noise at 90° azimuth, and (4) speech in 65 dBA noise with noise at 270° azimuth. Speech materials were always presented at 0° azimuth. Overall mean scores ranged from 29.9 dBA for the quiet condition to 63.4 dBA for the noise at 0° azimuth condition. A significant difference was found between Lists 13 and 16 only. This was attributed to audibility differences among the listeners. Therefore, the 25 HINT lists should be considered equivalent for older populations with similar hearing impairment. The HINT lists can be used for relative measures, such as comparison of aided versus unaided sentence SRTs or comparison of 2 different hearing aids.