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281.
Breena Holland 《环境政策》2017,26(3):391-412
Climate adaptation politics presents both obstacles and opportunities for correcting inequities that leave some communities especially vulnerable to climate-related environmental harms. By revealing these obstacles and opportunities, theories of procedural justice can help to identify procedural reforms and political strategies that advance the interests of vulnerable populations. An account of procedural justice is proposed that foregrounds the capability for political control over one’s environment, defined as having the political power to influence adaptation decisions. While the variables shaping this capability in the politics of environmental injustice often interact in ways that reproduce environmental inequities, adaptation politics has the potential to produce more transformational outcomes. To illustrate this potential, differences between the politics of environmental injustice and the politics of climate adaptation are drawn on to sketch the basic features of a typology of vulnerable populations’ political capabilities in the politics of climate adaptation, before highlighting the potential points for intervention. 相似文献
282.
The capabilities of third world countries in dealing withenvironmental problems are often limited by available resources and the tremendous costs of environmental monitoring.This paper attempts to introduce a newmethodology that can be used to derive information aboutenvironmental quality in its spatial and temporal dimensions.This methodology, based on an inquiry-feedback network of 8,000families and iteration with controlled-feedback of expertcommunity, has been first tested in Shanghai, China andprocedurally can be divided into two steps: Base-year evaluationand forecasting. Fuzzy pattern recognition is introduced for thesubjective assessment of the citizens' feelings theirperceived environment and a four-round Delphi-Cross Impactanalysis is conducted for forecasting the environmental changesup to 2000. Results show that the base-year environmentalsituations were poor. In the foreseeable future, the conditionsfor housing, social services, public health, greenspace anddrinking water will be substantially improved. Due to the rapidgrowth of manufacturing, the city will continue its deteriorating trend of air and water quality into the next century according to the forecast. 相似文献
283.
K. E. Arnold 《Behavioral ecology and sociobiology》2000,48(5):385-391
Living with relatives can be beneficial to individuals via the evolution of kin-directed altruism, but this is tempered by
the increased risk of inbreeding. Therefore, in social species, the ability to recognise relatives can be highly advantageous.
This study focuses on kin discrimination in the Lake Eacham rainbowfish, Melanotaenia eachamensis, an endangered freshwater species from north-east Queensland, Australia. First, I examined kin recognition abilities when
a combination of both chemical and visual recognition cues was available. When given a choice of shoaling with same-sex groups,
females spent significantly longer with full-sibs rather than half-sibs, full-sibs rather than non-relatives and half-sibs
rather than non-relatives. Males spent significantly longer shoaling with full-brothers versus half-brothers, but showed no
other shoalmate preferences. Second, in the presence of only chemical cues, females did not discriminate among groups of different
levels of relatedness, but males showed a non-significant tendency to associate with full-sibs rather than non-relatives.
Male shoaling behaviour seemed to be more influenced by factors other than relatedness, e.g. intra-sexual competition. Finally,
I found that the shoaling preferences of females changed when exposed to groups of males. Females preferred to associate with
non-relatives rather than half-brothers and non-relatives rather than full-brothers. There was no significant difference in
the time spent with half-brothers versus full-brothers. Taken together, my results suggest that females have very good kin
recognition abilities. They prefer to shoal with female relatives but avoid male relatives, and so are able to balance the
benefits of nepotism and the costs of incest.
Received: 2 May 2000 / Revised: 26 July 2000 / Accepted: 30 July 2000 相似文献
284.
Kin recognition in the common lizard 总被引:4,自引:0,他引:4
Jean Paul Léna Michelle de Fraipont Jean Paul Léna 《Behavioral ecology and sociobiology》1998,42(5):341-347
The ability to recognize parents has never been reported in species in which parents do not provide care to their young;
in such species, only sibling recognition has been found. However, there may be several advantages of parent recognition,
even in the absence of parental care. We investigated the ability of neonates to recognize olfactory cues from both their
mother and siblings in the common lizard, Lacerta vivipara, a species without parental care. Juveniles from 264 gravid females were reared for 2 days either with their mother, with
another female, or separated from all other adults. Juveniles from some families were split into two or three groups so that
each juvenile was unfamiliar with a subset of its siblings. After 2 days, we offered the juveniles a choice of two nocturnal
shelters: one containing a lizard odor and the other without odor. The response to the odor of an unrelated and unfamiliar
adult was influenced by both the sex of the adult and the sex of the juvenile. Juveniles of both sexes recognized the odor
of their mother whether they were familiar with her or not (pre-natal determinism). Juveniles recognized familiar but not
unfamiliar siblings (post-natal determinism). In the wild, spatial association with kin declines shortly after birth. Thus,
recognition of the mother is likely to have biological relevance. Recognition of the mother may reduce competition and/or
enhance juvenile establishment.
Received: 15 May 1997 / Accepted after revision: 29 December 1997 相似文献
285.
Sexual selection in the zebra finch Taeniopygia guttata : condition, sex traits and immune capacity 总被引:5,自引:2,他引:3
The aim of this study was to test two hypotheses: (1) that condition-dependent secondary sexual traits reflect an individual's
immune capacity and (2) that immune capacity and secondary sexual traits covary with primary sex traits, specifically ejaculate
quality. We used the zebra finch Taeniopygia guttata as a study species, since the traits that females find attractive in males of this species, song rate and beak colour, are
well established. A paired experimental design comprising 31 pairs of brothers was used; for each pair, one male was assigned
to a control group provided with ad libitum food and no additional exercise, and the other male was assigned to an experimental
group which experienced additional exercise and a reduced rate of food intake. After 11 weeks, the experimental group differed
significantly from the control group in a range of variables, including body mass, haematocrit, granulocyte:lymphocyte (G:L)
ratio and several primary sex traits, indicating that condition in this group was reduced. Birds in the experimental group
showed a differential response to the treatment. We used the rank order in which birds could be captured by an experimenter
as an index of condition. Birds easily caught were assumed to be in poorer condition than those which were more difficult
to capture. Rank capture order was repeatable and was significantly correlated with the G:L ratio in the experimental group,
but not in the control group. In the experimental group, rank capture order was correlated significantly with both secondary
sex traits: birds in better condition had redder beaks and a higher song rate. However, beak colour and song rate did not
covary significantly, suggesting that these two traits provide different types of information. Secondary sex traits did not
covary with primary sex traits or any sperm features. Thus, there was no evidence for Trivers' sexual-competence hypothesis
or the phenotype-linked fertility hypothesis. We used four assays of immune capacity, two general (G:L ratio and spleen mass)
and two specific [antibody titres to sheep red blood cells (SRBCs) and Brucella abortus (BA)]. The G:L ratio was significantly higher in the experimental group, spleen mass (absolute and relative) did not differ
between the groups, anti-SRBC antibody titres were significantly higher in the control group (contrary to expectation), and
anti-BA antibody titres were close to being significantly lower in the experimental group. Within the experimental group,
there was no evidence that antibody titres covaried with secondary sex traits. Although we demonstrated that beak colour and
song rate were condition dependent, our experiment provided no evidence that either of these traits covaried with immune capacity
or sperm features.
Received: 9 February 1998 / Accepted after revision: 5 September 1998 相似文献
286.
Introduction: Alcohol-related impairment is a key contributing factor in traffic crashes. However, only a few studies have focused on pedestrian impairment as a crash characteristic. In Louisiana, pedestrian fatalities have been increasing. From 2010 to 2016, the number of pedestrian fatalities increased by 62%. A total of 128 pedestrians were killed in traffic crashes in 2016, and 34.4% of those fatalities involved pedestrians under the influence (PUI) of drugs or alcohol. Furthermore, alcohol-PUI fatalities have increased by 120% from 2010 to 2016. There is a vital need to examine the key contributing attributes that are associated with a high number of PUI crashes. Method: In this study, the research team analyzed Louisiana’s traffic crash data from 2010 to 2016 by applying correspondence regression analysis to identify the key contributing attributes and association patterns based on PUI involved injury levels. Results: The findings identified five risk clusters: intersection crashes at business/industrial locations, mid-block crashes on undivided roadways at residential and business/residential locations, segment related crashes associated with a pedestrian standing in the road, open country crashes with no lighting at night, and pedestrian violation related crashes on divided roadways. The association maps identified several critical attributes that are more associated with fatal and severe PUI crashes. These attributes are dark to no lighting, open country roadways, and non-intersection locations. Practical Applications: The findings of this study may be used to help design effective mitigation strategies to reduce PUI crashes. 相似文献
287.
The growing diversity of image scenes brings a great challenge to human activity recognition in practice. Traditional activity recognition methods cannot satisfy the demand of precise action recognition in complex scenes. In this work, we build a training set of worker's activities on offshore drilling platform by collecting data from offshore drilling monitor, and then an improved multi-level convolutional pose machine (MCPM) method is proposed and trained to recognize activities of workers on the platforms. In human object detection, a multi-rule region proposal marker algorithm is developed to separate the seawater area, and the ducts of similar personnel is pre-discriminated by support vector machine. We use the characteristics of the human body key-points not affected by complex background noise to assist the detection of the human target. As results, it shown that our method performs better than Faster-RCNN, MobileNet-SSD and SSD algorithms in detecting human target on the offshore drilling platform, and achieves well accuracy in recognizing many key activities. To our best acknowledge, it is the first attempt of using deep model to recognize worker's activities on offshore drilling platform. 相似文献
288.
针对现有的火灾火焰图像识别方法在光照和红花等类似火焰干扰的复杂环境下存在错检和漏检的问题, 提出一种基于SSD_MobileNet的复杂环境火焰区域标记方法。首先,将深度卷积神经网络SSD300的基础卷积网络VGG16替换为MobileNet网络,应用深度可分离卷积,降低网络参数,进而构建一种火焰图像检测的SSD_MobileNet模型;然后,迁移第一次训练模型所有的卷积层参数,初始化新的待训练模型;最后,加入新的数据样本用于削弱光照、红花等干扰对象的影响。通过与SSD300、以及深度学习的目标检测算法Faster R-CNN和YOLOv3-tiny对比,实验结果表明,构建的火焰检测和火焰区域标记SSD_MobileNet模型的综合性能优于Faster R-CNN和YOLOv3-tiny模型,更适用于实时火焰检测领域。 相似文献
289.
大气环境质量评价的属性识别法 总被引:17,自引:0,他引:17
阐述了评价大气环境质量的属性识别法,介绍了属性识别理论模型和属性权重的确定方法,并根据GB 3095—1996((大气环境质量标准》,分别采用模糊数学综合评价法和属性识别法对武汉市大气环境监测结果进行了实例评价,结果表明,用属性识别法评价的结果比用模糊数学综合评价法评价的结果更能反映真实情况。 相似文献
290.
Sigal Lahav Victoria Soroker Robert K. Vander Meer Abraham Hefetz 《Behavioral ecology and sociobiology》1998,43(3):203-212
This study compares two basic models for the origin and maintenance of colony gestalt odor in the polygynous ant species
Cataglyphis niger. In the first model, queens are centers of de novo biosynthesis and distribution of recognition odors (“queen-centered” model);
in the second, colony odors are primarily synthesized and distributed by workers (“worker-centered” model). We tested the
behavioral patterns that are predicted from each model, and verified by biochemical means the distributional directionality
of these signals. Encounters between nestmates originating from split colonies were as amicable as between nestmates from
non-split colonies; queenless ants were as aggressive as their queenright nestmates, and both were equally aggressed by alien
ants. These results indicate that queens have little impact on the recognition system of this species, and lend credence to
the worker-centered model. The queen-centered model predicts that unique queen substances should be produced in appreciable
quantities and that, in this respect, queens should be more metabolically active than workers. Analysis of the chemical composition
of postpharyngeal glands (PPGs) or cuticular extracts of queens and workers revealed high similarity. Quantitatively, queens
possessed significantly greater amounts of hydrocarbons in the PPG than workers, but the amount on the thoracic epicuticle
was the same. Queens, however, possess a lower hydrocarbon biosynthesis capability than workers. The biochemical evidence
thus refutes the queen-centered model and supports a worker-centered model. To elucidate the directionality of cue distribution,
we investigated exchange of hydrocarbons between the castes in dyadic or group encounters in which selective participants
were prelabeled. Queens tended to receive more and give less PPG content, whereas transfer to the epicuticle was low and similar
in all encounters, as predicted from the worker-centered hypothesis. In the group encounters, workers transferred, in most
cases, more hydrocarbons to the queen than to a worker. This slight preference for the queen is presumably amplified in a
whole colony and can explain their copious PPG content. We hypothesize that preferential transfer to the queen may reflect
selection to maintain her individual odor as close to the average colony odor as possible.
Received: 4 November 1997 / Accepted after revision: 5 February 1998 相似文献