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61.
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Long-term behavioral tracking can capture and quantify natural animal behaviors, including those occurring infrequently. Behaviors such as exploration and social interactions can be best studied by observing unrestrained, freely behaving animals. Weakly electric fish (WEF) display readily observable exploratory and social behaviors by emitting electric organ discharge (EOD). Here, we describe three effective techniques to synchronously measure the EOD, body position, and posture of a free-swimming WEF for an extended period of time. First, we describe the construction of an experimental tank inside of an isolation chamber designed to block external sources of sensory stimuli such as light, sound, and vibration. The aquarium was partitioned to accommodate four test specimens, and automated gates remotely control the animals'' access to the central arena. Second, we describe a precise and reliable real-time EOD timing measurement method from freely swimming WEF. Signal distortions caused by the animal''s body movements are corrected by spatial averaging and temporal processing stages. Third, we describe an underwater near-infrared imaging setup to observe unperturbed nocturnal animal behaviors. Infrared light pulses were used to synchronize the timing between the video and the physiological signal over a long recording duration. Our automated tracking software measures the animal''s body position and posture reliably in an aquatic scene. In combination, these techniques enable long term observation of spontaneous behavior of freely swimming weakly electric fish in a reliable and precise manner. We believe our method can be similarly applied to the study of other aquatic animals by relating their physiological signals with exploratory or social behaviors.  相似文献   
63.
黔中喀斯特山地城市景观稳定性评价与特征分析   总被引:2,自引:0,他引:2  
张欣  王志杰 《生态学报》2022,42(13):5243-5254
城市景观稳定性是对城市生态环境进行分析和评价的基础,对城市景观生态安全格局和景观可持续性具有十分重要的意义。以典型喀斯特山地城市贵阳市为研究对象,以2008年、2013年和2017年景观类型为主要数据。运用蔓延度指数、斑块密度和总边缘对比度构建景观稳定性评价模型,在分析2008-2017年景观格局变化状况的基础上评价景观稳定性时空特征。并运用探索性空间数据分析方法揭示贵阳市景观稳定性时空演变规律和冷热点特征。结果表明:(1)2008-2017年贵阳市景观格局发生剧烈变化,耕地面积大幅减少,林地和建设用地面积持续增加,景观破碎化程度加剧,但破碎化趋势有所减缓。(2)10年间,贵阳市景观稳定性水平整体较低,以不稳定和较不稳定为主,表现出"先降低、后提高,总体略有降低"的趋势。(3)贵阳市景观稳定性的空间分布与演变具有明显空间聚集效应,全局Moran''s I指数介于0.2008-0.4005之间,但聚集趋势呈"总体减弱,小幅提高"的特征;此外,景观稳定性热点区主要集中在城镇建设用地或林地斑块相对集中连片、完整的区域。研究结果可为喀斯特山地城市景观空间格局优化、生态安全网络格局构建和生态文明城市建设提供重要的科学依据。  相似文献   
64.
This article discusses the trend in the development of testing from maximum regimentation of the test-takers’ activity (where they solve problems clearly formulated by the creator with a single correct answer) to diagnostic problematic situations that are very new and indefinite with an open beginning and an open end. With increasing frequency, the open beginning used in testing presupposes a freedom of independent formulation of one’s own research questions of the reality being studied and a search for answers while interacting with that reality. The emergence of mass testing of exploratory behavior is a reflection of the conviction that one of the key abilities that will be required in the very near future is the ability to cope with uncertainty and novelty, including by actively investigating them.

The discussion deals with the problems of testing intelligence and creativity in conditions of novelty and uncertainty, including the “judging problem.” It is pointed out that any thinking test, especially a test of creative thinking, is also an implicit (albeit perhaps not conscious) claim by its developers that their wisdom is virtually unsurpassed. After all, it is assumed that any person’s intelligence and creativity that unfold in a new situation may be described in the context of the model produced by the creative intellect of the test’s developer and, hence, by a more powerful “superintellect.” The errors that are practically inevitable with such an approach can be corrected in a dialog among various groups of researchers or, to the contrary, may be deepened if criticism is shut off.

The article analyzes a fundamental methodological error of creativity testing—the “standard list of creative answers” drawn up by the test-maker in advance, against which the participants’ solutions are checked. This error is explored in the case of an invention-oriented task in the international scholastic test PISA 2012, based on which the education ratings of countries are constructed.

An optimistic thesis is offered: no matter how successful testing is, humankind will never be fully prepared to determine its creative potential, due to its forward development. Without diagnostic tools, however, it will be far less prepared; they are a new and important part of that potential.  相似文献   
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66.
Abstract

The Indo‐Pacific humpback dolphin (Sousa chinensis) is under severe threat in Chinese waters. Only four small populations of this dolphin are known to survive in the East China Sea and South China Sea. We conducted exploratory surveys from June to September 2005, and found a population of humpback dolphins in Leizhou Bay. Thirty‐eight individuals were identified and catalogued, of which 26 were photographed and re‐identified on more than one occasion, and nine were sighted on five or more occasions each. Our preliminary estimate of the size of the Leizhou population is about 237 individuals, second only to the Pearl River estuary population. We suggest that Leizhou Bay has the potential to serve as a “humpback dolphin sanctuary” in Chinese waters.  相似文献   
67.
Indicators of environmental adequacy relevant to the well-being of small felids are developed by examining, in 4 captive leopard cats, interrelationships between behavioral and adrenocortical responses to changes in housing conditions. Singly housed cats were moved from their barren home cage (Cage 1, baseline) sequentially to 2 new, barren housing situations (Cages 2 and 3; ≈ 10 weeks/cage). Urinary cortisol concentrations, stereotypic pacing, and hiding frequencies were transiently increased for 1 week after translocation to Cage 2. After translocation to Cage 3, cortisol concentrations and hiding also were increased for the first week. However, conditions in Cage 3 were determined to be aversive to the cats, as evidenced by cortisol concentrations that remained chronically elevated for the entire 10-week period. Exploratory behavior was suppressed during this period. When Cage 3 was enriched with a complex of branches and hiding places, urinary cortisol concentrations and stereotypic pacing decreased, and exploration increased. Concealment locations that camouflage were more often used for lying down when urinary cortisol was elevated. These results suggest that reduced exploratory behavior is an indicator of chronic exposure to aversive environmental conditions. Stereotypic pacing may not necessarily increase when adrenocortical activity increases. The results also suggest that enrichment facilitates coping with aversive stimulation by providing behavioral options to confined felids. To promote the welfare of small felids, appropriate camouflaged hiding places should be provided and enrichment programs developed to stimulate exploratory behavior. © 1993 Wiley-Liss, Inc.  相似文献   
68.
The objective of this study was to investigate if female growing pigs spend similar amounts of time exploring a wooden stick as they do exploring enrichment material regardless of its proximity to the feeder. Forty-eight pigs aged 18 to 26 weeks allocated to 16 pens with three pigs per pen were studied. Fifty percent of the pens had a wooden stick beside the feeder, and the rest had a similar stick opposite to the feeder. Two observers assessed the pigs by means of scan and focal sampling. The pigs spent more time (p < .0001) exploring the wood during the first week than during the rest of the study (10.9% vs 3.6%). The pigs with the wood close to the feeder spent less (p = .0001) time resting (29.9%) and more (p < .0001) time exploring (6.3%) the wood than did pigs with the wood opposite to the feeder (32.4% and 2.5%, respectively). In conclusion, a wooden stick placed close to the feeder was associated with more exploratory behaviorcompared with a similar stick placed opposite to the feeder.  相似文献   
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70.
Contemporary cycles for copper and zinc are coanalyzed with the tools of exploratory data analysis. One-year analyses (circa 1994) are performed at three discrete spatial levels-country (52 countries that comprise essentially all anthropogenic stocks and flows of the two metals), eight world regions, and the planet as a whole-and are completed both in absolute magnitude and in per capita terms. This work constitutes, to our knowledge, the first multiscale, multilevel analysis of anthropogenic resources throughout their life cycles. The results demonstrate that (1) A high degree of correlation exists between country-level copper and country-level zinc rates of fabrication and manufacturing, entry into use, net addition to in-use stocks, discard, and landfilling; (2) Regional-level rates for copper and zinc cycle parameters show the same correlations as exist at country level; (3) On a per capita basis, countries add to in-use stock almost 50% more copper than zinc; (4) The predominant discard streams for copper and zinc at the global level are different for the two metals, and relative rates of different loss processes differ geographically, so that resource recovery policies must be designed from metalspecific and location-specific perspectives; (5)When absolute magnitudes of life-cycle flows are considered, the standard deviations of the data sets decrease from country level to regional level for both copper and zinc, which is not the case for the per capita data sets, where the statistical properties of the data sets for both metals approach being independent of spatial level, thus providing a basis for predicting unmeasured per capita metal flow behavior.  相似文献   
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