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931.
932.
Journal of Biological Physics - A molecular beam spectrometer using dielectrophoresis is described which should be useful in studies of molecular polarizabilities, dipole moments, rotational energy... 相似文献
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Coughlan Neil E. O’Hara Shane Crane Kate Dick Jaimie T. A. MacIsaac Hugh J. Cuthbert Ross N. 《Wetlands Ecology and Management》2020,28(2):397-402
Wetlands Ecology and Management - Biosecurity protocols designed to prevent further spread of invasive alien species have become a key component of invader management strategies. However,... 相似文献
935.
John D'Andrea Steven Chalfin Carrie Crane Donald Marchello Robert Garay Donald Hatcher John Ziriax 《Bioelectromagnetics》2010,31(4):324-333
Microwave‐induced corneal endothelial damage was reported to have a low threshold (2.6 W/kg), and vasoactive ophthalmologic medications lowered the threshold by a factor of 10–0.26 W/kg. In an attempt to confirm these observations, four adult male Rhesus monkeys (Macaca mulatta) under propofol anesthesia were exposed to pulsed microwaves in the far field of a 2.8 GHz signal (1.43 ± 0.06 µs pulse width, 34 Hz pulse repetition frequency, 13.0 mW/cm2 spatial and temporal average, and 464 W/cm2 spatial and temporal peak (291 W/cm2 square wave equivalent) power densities). Corneal‐specific absorption rate was 5.07 W/kg (0.39 W/kg/mW/cm2). The exposure resulted in a 1.0–1.2 °C increase in eyelid temperature. In Experiment I, exposures were 4 h/day, 3 days/week for 3 weeks (nine exposures and 36 h total). In Experiment II, these subjects were pretreated with 0.5% Timolol maleate and 0.005% Xalatan® followed by 3 or 7 4‐h pulsed microwave exposures. Under ketamine–xylazine anesthesia, a non‐contact specular microscope was used to obtain corneal endothelium images, corneal endothelial cell density, and pachymetry at the center and four peripheral areas of the cornea. Ophthalmologic measurements were done before and 7, 30, 90, and 180 days after exposures. Pulsed microwave exposure did not cause alterations in corneal endothelial cell density and corneal thickness with or without ophthalmologic drugs. Therefore, previously reported changes in the cornea exposed to pulsed microwaves were not confirmed at exposure levels that are more than an order of magnitude higher. Bioelectromagnetics 31:324–333, 2010. Published 2010 Wiley‐Liss, Inc. 相似文献
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The synthesis of nuclear histones in early embryogenesis 总被引:2,自引:0,他引:2
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Rubimedin particles on chloroplast lamellae 总被引:1,自引:0,他引:1
940.
Sabrina Engesser Jodie M. S. Crane James L. Savage Andrew F. Russell Simon W. Townsend 《PLoS biology》2015,13(6)
The ability to generate new meaning by rearranging combinations of meaningless sounds is a fundamental component of language. Although animal vocalizations often comprise combinations of meaningless acoustic elements, evidence that rearranging such combinations generates functionally distinct meaning is lacking. Here, we provide evidence for this basic ability in calls of the chestnut-crowned babbler (Pomatostomus ruficeps), a highly cooperative bird of the Australian arid zone. Using acoustic analyses, natural observations, and a series of controlled playback experiments, we demonstrate that this species uses the same acoustic elements (A and B) in different arrangements (AB or BAB) to create two functionally distinct vocalizations. Specifically, the addition or omission of a contextually meaningless acoustic element at a single position generates a phoneme-like contrast that is sufficient to distinguish the meaning between the two calls. Our results indicate that the capacity to rearrange meaningless sounds in order to create new signals occurs outside of humans. We suggest that phonemic contrasts represent a rudimentary form of phoneme structure and a potential early step towards the generative phonemic system of human language. 相似文献