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A new method for obtaining dermatoglyphic prints is described. Photographic film is used enabling prints to be obtained directly, and at any enlargement. The sweat-pores can be shown in detail, and counted.  相似文献   
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A breeding population of black-browed albatrosses has been known to exist at the Ildefonso Archipelago, Chile, for >90 years but the population has never been censused using scientifically defendable methods. To estimate population size, and examine the accuracy and practicality of various census methods, the population was censused in the 2002/2003 breeding season using (a) ground-truthed aerial photography, (b) yacht-based photography, (c) ground counts, (d) quadrat sampling and (e) point-distance sampling. Compared to ground-truthed aerial photography (judged the most accurate) yacht-based photography underestimated population size by 55%, ground counts by 13%, quadrat sampling by 11% and point-distance sampling by 9%. Ground-truthed air photography revealed that in the 2002/2003 breeding season 47,000 pairs of black-browed albatrosses bred at the Ildefonso Archipelago. A repeat aerial census in 2006 suggested the size of the breeding population had not changed in the 4 years between the two censuses. After the Falkland Islands/Islas Malvinas, South Georgia and Diego Ramirez, the Ildefonso Archipelago holds the fourth largest population of black-browed albatrosses in the world.  相似文献   
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The present study was designed to assess a monkey's perception of specific visual stimuli by measuring both the behavioral responses and duration of attention to the presentation of photographic slides. Five adult male cynomolgus macaques (Macaca fascicularis) were placed individually in an open field apparatus and presented a series of slides consisting of apples, a gorilla mask, a collage of colors, a human being, and a plain field. The slide of the gorilla mask followed by that of the human being received the most attention while the plain field received the least. In addition, the gorilla mask and human being elicited a range of behavioral responses with the higher ranking animals displaying a greater number of aggressive responses and the lower ranking animals displaying a greater number of submissive gestures. Taken together, these data would suggest that the slides of the gorilla mask and the human being were perceived by the monkeys as threatening. These results are consistent with a continuing theme observed among a number of studies of primate social perception — namely, that potentially threatening stimuli are a significant determinant of visual observing.  相似文献   
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Abstract The effect of glycine on phototrophically growing Chromatium vinosum D was investigated in the presence and absence of various amino acids. Inhibition of autotrophic cells was more pronounced than that of heterotrophic cells. Cells of growth-inhibited cultures were misshaped, showing vacuolation and partial protoplast formation. Cells exposed to glycine in the presence of equimolar amounts of either d - or l -alanine did not show any inhibition of growth. Neither serine, leucine, valine, isoleucine nor α-aminoisobutyric acid could counteract the inhibition of growth by glycine. The inhibitory effect of glycine on growth is thus likely to be caused by a competition between glycine and alanine during cell wall synthesis. The possible functions of glycine transport system(s) in the natural habitat of C. vinosum are discussed.  相似文献   
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A radiographic technique for processing a large number of human crania was developed to aid in the diagnosis of porotic hyperostosis in a large skeletal population. These images are made directly onto photographic paper, thereby reducing costs and increasing the rate of processing. The technique is especially well suited for radiographing human skeletal material and gives excellent diagnostic image quality.  相似文献   
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Bacteriorhodopsin and ε 15 bacteriophage were used as biological test specimens to evaluate the potential structural resolution with images captured from a 4k × 4k charge-coupled device (CCD) camera in a 300-kV electron cryomicroscope. The phase residuals computed from the bacteriorhodopsin CCD images taken at 84,000× effective magnification averaged 15.7° out to 5.8-Å resolution relative to Henderson’s published values. Using a single-particle reconstruction technique, we obtained an 8.2-Å icosahedral structure of ε 15 bacteriophage with the CCD images collected at an effective magnification of 56,000×. These results demonstrate that it is feasible to retrieve biological structures to a resolution close to 2/3 of the Nyquist frequency from the CCD images recorded in a 300-kV electron cryomicroscope at a moderately high but practically acceptable microscope magnification.  相似文献   
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Contrasting patterns of pigmentation, such as those associated with crypsis and aposematism, are common in many taxa. In order to determine why patterning varies among individuals or populations, it is important to quantify how these patches of pigment are arranged. Here we present a simple technique for measuring areas of pigmentation as well as their spatial distribution, and demonstrate its application to the study of substrate-associated patterning in shore crabs (Carcinus maenas L.). The results, based on a virtual grid laid over digital images of crab carapaces, allow for correlations to be made among sample populations. The technique, or variations of it, can be applied to any situation where two-dimensional dichromatic patterns need to be quantified.  相似文献   
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兽类和鸟类多样性的监测是生物多样性保护中的重要一环。2017年4月至2018年5月,按照网格法在位于陕西省西安市周至县的老县城国家级自然保护区布设了36台红外相机,对保护区内大中型兽类和林下鸟类多样性进行调查。累积7 835个相机工作日,获得野生动物独立有效照片1 915张,共鉴定出32种鸟类和兽类物种,隶属8目18科,其中被IUCN红色名录评估为濒危(EN)、易危(VU)和近危(NT)的物种分别有2种、4种和3种。相对丰富度指数最高的为羚牛(Budorcas taxicolor)(IRA=36.81);夏季(7.68)和秋季(7.81)物种拍摄率大于春季(4.65)和冬季(4.30),不同季节拍摄到的物种数和物种多样性指数差异不显著。不同海拔段物种拍摄率、物种数和物种多样性指数均不具有明显差异。濒危物种中的羚牛不同海拔段拍摄率存在明显差异。主成分分析表明,拍摄物种与相机位点之间相关性较强,这与相机位点附近的生境条件有关。研究结果初步掌握了老县城保护区内大中型兽类和林下鸟类种类组成、相对多度及分布状况,为未来保护区野生动物资源保护和管理提供基础资料。  相似文献   
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Interest in their animate environment was studied in a captive group of 11 stumptailed macaques (Macaca arctoides). Subjects were shown projected photographic slides, most of which showed a single individual primate or non-primate. The measure of interest was the duration of viewing. Results showed that adult females exhibited more interest towards stumptailed macaques versus other macaques species, and towards adult females carrying infants versus adult females alone. Data concerning non-primates showed that subjects were especially interested by photographs of felids; this effect was partly due to the presence of two frontal and conspicuous eyes in felids.  相似文献   
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