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931.
H. A. GLEASON JR. 《American anthropologist》1972,74(6):1490-1492
932.
CHRIS KIRKPATRICK COURTNEY J. CONWAY KATIE M. HUGHES JAMES C. DEVOS JR. 《The Journal of wildlife management》2007,71(1):231-237
Abstract: Estimates of population trend for the interior subspecies of band-tailed pigeon (Patagioenas fasciata fasciata) are not available because no standardized survey method exists for monitoring the interior subspecies. We evaluated 2 potential band-tailed pigeon survey methods (auditory and call-broadcast surveys) from 2002 to 2004 in 5 mountain ranges in southern Arizona, USA, and in mixed-conifer forest throughout the state. Both auditory and call-broadcast surveys produced low numbers of cooing pigeons detected per survey route (x̄ ≤ 0.67) and had relatively high temporal variance in average number of cooing pigeons detected during replicate surveys (CV ≥ 161%). However, compared to auditory surveys, use of call-broadcast increased 1) the percentage of replicate surveys on which ≥1 cooing pigeon was detected by an average of 16%, and 2) the number of cooing pigeons detected per survey route by an average of 29%, with this difference being greatest during the first 45 minutes of the morning survey period. Moreover, probability of detecting a cooing pigeon was 27% greater during call-broadcast (0.80) versus auditory (0.63) surveys. We found that cooing pigeons were most common in mixed-conifer forest in southern Arizona and density of male pigeons in mixed-conifer forest throughout the state averaged 0.004 (SE = 0.001) pigeons/ha. Our results are the first to show that call-broadcast increases the probability of detecting band-tailed pigeons (or any species of Columbidae) during surveys. Call-broadcast surveys may provide a useful method for monitoring populations of the interior subspecies of band-tailed pigeon in areas where other survey methods are inappropriate. 相似文献
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This investigation was conducted to examine the contribution of intrasite variation on the volar forearm to the overall variation in irritation under the conditions of a soap chamber test. Six sites on each forearm of human volunteers were patched with an eight percent aqueous solution of a commercial bar soap, known to be moderately irritating. Clinical evaluations of the sites were made independently by two judges twenty-four hours after the first patch application and six hours following applications conducted over the next four consecutive days. Site to site variability was estimated to be only 3.2% of the total variance component. It is suggested that as with any biologic assay, this variance can be reduced by an increase in the number of panelists. 相似文献
936.
At a small supplied concentration (3–5 mM), diallyl disulfide (DADS) and diallyl monosulfide (DAMS), compounds previously shown to have both tumoricidal and protective effects against carcinogenesis, affected the growth of components of the normal anaerobic gut microflora. Organisms that were affected by DAMS and DADS includedBacteroides ruminicola, Bacteroides succinogenes, Butyrivibrio fibrisolvens, Ruminococcus albus, Ruminococcus flavefaciens, Ruminococcus bromii, andPeptostreptococcus productus. Organisms found unaffected, over the same supplied concentration range, includedBacteroides fragilis, Bacteroides vulgatus, Fusobacterium necrophorum, Fusobacterium nucleatum, andSelenomonas ruminantium. In addition to their direct effects upon host cell physiology, the active components of garlic oil may exert modifying effects on the nature and function of the predominant gut microflora of warm-blooded animals. 相似文献
937.
Abstract. Female preferences for conspicuous male calls have been documented in many groups. However, relatively few studies have examined the metabolic costs associated with the production of call types preferred by females. We measured the oxygen consumption of calling male Gryllus lineaticeps Stål crickets using closed chamber respirometry. Calling song was recorded concurrently. The average increase in mass-specific oxygen consumption during calling was 2.7 times basal rates of oxygen consumption, and calling males consumed approximately 1.2ml O2 g-l h-1 . Oxygen consumption increased with increasing chirp rate and pulse duration, but not with increasing chirp duration. Females of this species prefer higher chirp rates, thus some call types that increase the male's attractiveness to females require more metabolic energy to produce. 相似文献
938.
Chlorophyll content decreased when excised lemon fruits were exposed to light. A quantitative model for the photodestruction of chlorophyll exhibited reasonable agreement with data on in vivo destruction of chlorophyll. Photodestruction of chlorophyll was enhanced by treating fruit with 2′,4′-dichloro-l-cyanoethane-sulphonanilide (R33417). Measurable enhancement of chlorophyll destruction was observed with concentrations of R33417 as low as 10 μg/l. Maximum activity was achieved at approximately 600 μg/1. R33417 treatment enhanced photodestruction of chlorophyll to a greater extent at higher photon flux densities. 相似文献
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