Publications by authors named "D S Houser"
A primary feature of bat and dolphin biosonar is the ability to measure echo-delay, both to determine absolute target range and to resolve range differences between targets. Measurements of range (i.e.
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- Researchers initiated a catch-and-release program to study the hearing of adolescent minke whales during their summer migration, addressing knowledge gaps.
- In 2023, two minke whales underwent hearing tests that measured their auditory brainstem response and examined their hearing frequency range.
- Findings reveal minke whales can detect sound frequencies up to 45 to 90 kilohertz, shedding light on how anthropogenic noise may impact them and similar baleen whale species.
Two bottlenose dolphins (Tursiops truncatus) were trained to discriminate double-click synthetic "echoes" differing in inter-highlight interval (IHI). In the first experimental task, dolphins passively listened to background (S-) stimuli with constant IHI and responded on discriminating a change to target (S+) stimuli with a slightly increased IHI. The second task was similar, but the highlights were assigned random, frequency-independent phase angles.
View Article and Find Full Text PDFAuditory brainstem responses (ABRs) were measured at 57 kHz in two dolphins warned of an impending intense tone at 40 kHz. Over the course of testing, the duration of the intense tone was increased from 0.5 to 16 s to determine if changes in ABRs observed after cessation of the intense sound were the result of post-stimulatory auditory fatigue or conditioned hearing attenuation.
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- DNA experiences high mechanical stress from bending and twisting in various biological structures, such as nucleosomes and virus capsids, affecting essential processes like packaging and gene regulation.
- A new ligation assay developed on nicked DNA circles shows that DNA can unwind to over 11 base pairs per turn when curving tightly, challenging the conventional belief that its helical structure remains consistent.
- This research necessitates a re-evaluation of DNA's mechanical model and its implications for molecular processes involving tightly bent DNA.