Objective Measure of Listening Effort in HearingImpaired Individuals With and Without Tinnitus

BACKGROUND

Tinnitus is a perception of sound in the brain without any external stimulus. Tinnitus patients often complain of more efforts required in listening. They may be ineffective in inhibiting their attention, driven to irrelevant ringing sounds in their ear rather than attending to the relevant target speech stimulus. The study's objective was to evaluate an allocation of cognitive resources among tinnitus patients for concurrent tasks required for understanding speech using an objective dual-task paradigm to assess listening effort.

METHODS

We recruited 40 participants with mild to moderately severe sloping sensorineural hearing loss within 60-70 years. They were subgrouped into control and clinical groups. The clinical group had a severe degree of tonal tinnitus bilaterally. The objective listening task used listening effort, and a subjective questionnaire to assess the effort in listening was assessed by each study participant.

RESULTS

The results indicated poorer recognition and reduced recall scores in a clinical group than the control group in each signal-to-noise ratio. The recall score in objective listening effort measurement was strongly correlated with subjective questions assessed effort in listening among the clinical group at each signal-to-noise ratio. However, in the control group, the correlation was to a mild degree at 0 dB signal-to-noise ratio only.

CONCLUSION

Annoyance caused by tinnitus disrupts attention, thereby limiting the effective use of cognitive resources for concurrent speech processing and recalling reflected in the listening effort task.

Ongoing declines of woodland birds: Are restoration plantings making a difference?

Woodland birds are a species assemblage of conservation concern, and their persistence in fragmented agricultural landscapes is dependent on both the preservation of existing woodland remnants and the implementation of restoration plantings. However, little is known about the habitat-use and persistence of birds in fragmented agricultural landscapes. We present a detailed, population-oriented study of woodland birds in temperate eucalypt woodland restoration plantings and remnant woodland patches in the South-west Slopes bioregion of New South Wales, Australia. First, we undertook a 3-yr mark-recapture project to assess annual survival and site fidelity in restoration plantings and woodland remnants. We supplemented our recapture efforts with resightings of color-banded individuals. Second, we tracked individual birds of two species, Superb Fairywren (Malurus cyaneus) and Willie Wagtail (Rhipidura leucophrys), and documented snapshots of their home ranges and movement patterns during the breeding season. Annual survival in the woodland bird assemblage was lower than expected (51%). Home ranges of the Superb Fairywren were positively correlated with patch size, and were constrained by patch edges in linear sites. Superb Fairywrens and Willie Wagtails were more likely to travel longer distances between substrates while foraging in linear sites. Willie Wagtails engaged in significant gap-crossing (up to 400 m) between adjacent habitat patches. Our findings indicate that (1) patch isolation and certain patch configurations place resident birds at an energetic disadvantage, and (2) in our study area, woodland bird populations are continuing to decline. We recommend landscape-scale habitat restoration programs aim to address ongoing population declines. Studies such as ours conducted over longer time periods would provide a deeper understanding of habitat use and population processes of woodland birds in fragmented agricultural landscapes.

Filters: When, Why, and How (Not) to Use Them

Filters are commonly used to reduce noise and improve data quality. Filter theory is part of a scientist's training, yet the impact of filters on interpreting data is not always fully appreciated. This paper reviews the issue and explains what a filter is, what problems are to be expected when using them, how to choose the right filter, and how to avoid filtering by using alternative tools. Time-frequency analysis shares some of the same problems that filters have, particularly in the case of wavelet transforms. We recommend reporting filter characteristics with sufficient details, including a plot of the impulse or step response as an inset.

Prevalence and Pattern of Phantom Ringing and Phantom Vibration among Medical Interns and their Relationship with Smartphone Use and Perceived Stress

BACKGROUND

Phantom sensations like phantom vibration (PV) and phantom ringing (PR)- the sensations of vibration and ringing of the phone when they are not, respectively-are among the latest in the category of "techno-pathology" to receive global attention. This study was conducted with the aim to estimate the prevalence of such sensations among medical interns and their association with perceived stress levels and smartphone usage pattern.

MATERIALS AND METHODS

Ninety-three medical interns using smartphone were recruited for the study. Data were collected anonymously using semi-structured questionnaire, perceived stress scale (PSS), and smartphone addiction scale-short version (SAS-SV). Data were analyzed using descriptive statistics, Chi-square test, independent t-test, ANOVA, and Pearson's correlation coefficient.

RESULTS

Fifty-nine percent students had a high level of stress, whereas 40% had problematic smartphone use. Sixty percent students experienced PV, whereas 42% experienced PR and both were significantly associated with higher frequency of phone use and the use of vibration mode. Mean SAS-SV score was significantly lower in students who did not perceive PR/PV, whereas mean PSS score was significantly lower in students who did not perceive PV.

CONCLUSION

This study confirms findings from other national and international researches about the experience of cell phone phantom sensations and their relationship with the pattern of phone use and stress level. It also brings to light high levels of stress and problematic smartphone use among medical students during the internship.

Modelling and Experimental Verification of Step Response Overshoot Removal in Electrothermally-Actuated MEMS Mirrors

Micro-electro-mechanical system (MEMS) mirrors are widely used for optical modulation, attenuation, steering, switching and tracking. In most cases, MEMS mirrors are packaged in air, resulting in overshoot and ringing upon actuation. In this paper, an electrothermal bimorph MEMS mirror that does not generate overshoot in step response, even operating in air, is reported. This is achieved by properly designing the thermal response time and the mechanical resonance without using any open-loop or closed-loop control. Electrothermal and thermomechanical lumped-element models are established. According to the analysis, when setting the product of the thermal response time and the fundamental resonance frequency to be greater than Q/2π, the mechanical overshoot and oscillation caused by a step signal can be eliminated effectively. This method is verified experimentally with fabricated electrothermal bimorph MEMS mirrors.

ASSESSMENT OF THE RATES OF INJURY AND MORTALITY IN WATERFOWL CAPTURED WITH FIVE METHODS OF CAPTURE AND TECHNIQUES FOR MINIMIZING RISKS

Swan pipes, duck decoys, cage traps, cannon netting, and roundups are widely used to capture waterfowl in order to monitor populations. These methods are often regulated in countries with national ringing or banding programs and are considered to be safe, and thus justifiable given the benefits to conservation. However, few published studies have addressed how frequently injuries and mortalities occur, or the nature of any injuries. In the present study, rates of mortality and injury during captures with the use of these methods carried out by the Wildfowl & Wetlands Trust as part of conservation programs were assessed. The total rate of injury (including mild dermal abrasions) was 0.42% across all species groups, whereas total mortality was 0.1% across all capture methods. Incidence of injury varied among species groups (ducks, geese, swans, and rails), with some, for example, dabbling ducks, at greater risk than others. We also describe techniques used before, during, and after a capture to reduce stress and injury in captured waterfowl. Projects using these or other capture methods should monitor and publish their performance to allow sharing of experience and to reduce risks further.