3 research outputs found

    High Duty Cycle to Low Duty Cycle: Echolocation Behaviour of the Hipposiderid Bat <i>Coelops frithii</i>

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    <div><p>Laryngeally echolocating bats avoid self-deafening (forward masking) by separating pulse and echo either in time using low duty cycle (LDC) echolocation, or in frequency using high duty cycle (HDC) echolocation. HDC echolocators are specialized to detect fluttering targets in cluttered environments. HDC echolocation is found only in the families Rhinolophidae and Hipposideridae in the Old World and in the New World mormoopid, <i>Pteronotus parnellii</i>. Here we report that the hipposiderid <i>Coelops frithii</i>, ostensibly an HDC bat, consistently uses an LDC echolocation strategy whether roosting, flying, or approaching a fluttering target rotating at 50 to 80 Hz. We recorded the echolocation calls of free-flying <i>C. frithii</i> in the field in various situations, including presenting bats with a mechanical fluttering target. The echolocation calls of <i>C. frithii</i> consisted of an initial narrowband component (0.5Β±0.3 ms, 90.6Β±2.0 kHz) followed immediately by a frequency modulated (FM) sweep (194 to 113 kHz). This species emitted echolocation calls at duty cycles averaging 7.7Β±2.8% (<i>n</i>β€Š=β€Š87 sequences). <i>Coelops frithii</i> approached fluttering targets more frequently than did LDC bats (<i>C.frithii</i>, approach frequency β€Š=β€Š40.4%, <i>n</i>β€Š=β€Š80; <i>Myotis</i> spp., approach frequency β€Š=β€Š0%, <i>n</i>β€Š=β€Š13), and at the same frequency as sympatrically feeding HDC species (<i>Hipposideros armiger</i>, approach rate β€Š=β€Š53.3%, <i>n</i>β€Š=β€Š15; <i>Rhinolophus monoceros</i>, approach rate β€Š=β€Š56.7%, <i>n</i>β€Š=β€Š97). We propose that the LDC echolocation strategy used by <i>C. frithii</i> is derived from HDC ancestors, that this species adjusts the harmonic contents of its echolocation calls, and that it may use both the narrowband component and the FM sweep of echolocations calls to detect fluttering targets.</p></div

    Demographic data of solid tumor patients undergoing systemic cytotoxic chemotherapy and using prophylactic entecavir or lamivudine.

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    <p><sup><i>a</i></sup>Entecavir group included 6 head and neck cancers, 4 gynecologic cancers, and 7 genitourinary cancers. Lamivudine group included 31 head and neck cancers, 15 gynecologic cancers, and 11 genitourinary cancers.</p><p><sup><i>b</i></sup>SCC: systemic cytotoxic chemotherapy</p><p><sup><i>c</i></sup>ALT: alanine aminotransferase.</p><p><sup><i>d</i></sup>INR: international normalized ratio.</p><p>Demographic data of solid tumor patients undergoing systemic cytotoxic chemotherapy and using prophylactic entecavir or lamivudine.</p
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