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361.
Summary. Because generalist ants are aggressive towards foreign insects, the recognition of homopterans by tending ants is critical in ant/homopteran trophobiosis. Herein we report experimental evidence indicating that Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae) learn to associate the production of honeydew with the chemical characteristics of homopteran cuticle, suppressing ant aggression and allowing the ants to tend homopterans. Although chemically-mediated associative learning is well understood in honeybee foraging, to our knowledge, it has not been reported before in ant/homopteran trophobiosis.  相似文献   
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A case of cloacal exstrophy (CE) was detected by ultrasound as early as 22 weeks of gestation in association with myelocystocele complex, an unusual form of occult spinal dysraphism often associated with such a disease. The ultrasonographic diagnosis was made through the detection of a wavy cord-like segment of soft tissue protruding from the anterior abdominal wall, just below the umbilical cord insertion, strongly resembling the trunk of an elephant. Our article enforces the suggestion that the ultrasound elephant trunk–like image should be added to the existing major criteria for making prenatal diagnosis of CE. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
365.
While a small set of economic activities generates most of the direct environmental burdens, the complexity of connections within an economic system requires consideration of the effects caused by the interdependences between its different agents. To date, however, the input–output (I–O) subsystems literature has been limited to uncovering the intersectoral linkages of direct and indirect environmental impacts within an economy and the connections between sectors and private consumption have thus not attracted much attention. This paper proposes an I–O subsystems model that endogenously incorporates not only production sectors but also household consumption to capture the entire channel of environmental impacts. The empirical application focuses on carbon dioxide equivalent (CO2-eq.) emissions and water use associated with production sectors and households defined in the I–O table for a Spanish region, Extremadura. The results highlight the key role of the effects induced by private consumption on the environmental burdens of services.  相似文献   
366.
Food sovereignty movements (FSMs) globally have sought to rearrange relations between land, power, state actions and societal forces outside the state, towards a new ideal of democratised, egalitarian and ecological food systems. The question of how best to reach this ideal has vexed movements and scholars alike, with many anti-capitalist theorists proposing that because of the historical dedication of states to maintaining unequal and unsustainable capitalist relations, change must be pursued outside and against the state rather than through it (i.e. through “autonomism”). Yet, analysis of FSMs globally shows that autonomism is relative, partial and best seen as an aspirational ideal rather than a fixed dogma. This paper deepens this insight by analysing a case within the United States where a local direct action group promoted food sovereignty by illegally occupying public land. The case shows how even apparently autonomist movements can through influence on state and societal actors contribute to state-based “policy currents” that flow in the direction of food sovereignty. This mutual codetermination by actors in and out of state institutions of the possibility and shape of “policy currents” renders state–society relations as important, even to those interested in (relative) autonomism. This paper thus leaves behind dichotomous interpretations of (and recommendations for) FSMs vis-à-vis autonomism, in order to unpack the influence (in thought) and impact (in action) of autonomist tendencies in food sovereignty construction.  相似文献   
367.
It is increasingly expected that private actors play the role as entrepreneurs and front-runners in implementing climate measures, whereas empirical studies of the position, role and engagement of private actors are scarce. Situated in the context of urban planning, a critical arena for triggering climate transitions, the aim of this paper is to explore how Swedish property developers respond to climate change. Qualitative analyses of corporate policy documents and semi-structured interviews with property developers reveal a vast divergence between the written policies, where leadership ambitions are high, and how the practice of property development is discussed in interviews. In the latter, there is little evidence of property developers pursuing a forward-looking or cutting-edge climate change agenda. Instead, they are critical of increased public regulation for climate-oriented measures. Explanations both confirm previous studies, highlighting lack of perceived customer demand, uncertainty of financial returns and limited innovations, and add new elements of place-dependency suggesting that innovative and front-runner practices can only be realized in the larger urban areas. Municipalities seeking to improve their climate-oriented profile in urban planning by involving private property developers need to develop strategies to maneuver the variance in responses to increase the effectiveness of implementation.  相似文献   
368.
Titania nanomaterial with an anatase structure and 5.6 nm crystallite size and 280.7 m2 g−1 specific surface areas had been successfully prepared by sol–gel/hydrothermal route. The effect of pH as a type of autoclave and calcination was studied. Crystallite size and phase composition of the prepared samples were identified. X-ray diffraction analyses showed the presence of anatase with little or no rutile phases. The crystallite size of the prepared TiO2 with acidic catalyst was both smaller than that prepared with basic catalyst, and was increasing after acidic calcinations by a factor 4–5. Basic calcinations produced a specific increase of 1.5. Rutile ratio and the particle size were increased after calcination at 500 °C. However, TiO2 powder synthesized using a basic catalyst persisted the anatase phase and a loosely aggregation of particles. Anatase TiO2 as prepared with acidic catalyst in Teflon lined stainless steel autoclave demonstrated the highest photocatalytic activity for degradation of 2,6-dichlorophenol-indophenol under ultraviolet irradiation with t½ 0.8 min.  相似文献   
369.
The explosion properties of alkane/nitrous oxide mixtures were investigated and were compared with those of the corresponding alkane/oxygen and alkane/air mixtures. The explosion properties were characterized by three parameters: the explosion limit, explosion pressure, and deflagration index. For the same alkane, the order of the lower explosion limits (LELs) of the mixtures was found to be alkane/oxygen  alkane/air > alkane/nitrous oxide. In addition, the mixtures containing nitrous oxide tended to exhibit higher explosion pressures than the corresponding mixtures containing oxygen under fuel-lean conditions. The Burgess–Wheeler law was also observed to hold for the mixtures containing nitrous oxide.  相似文献   
370.
This paper assesses the communication and the use of climate scenarios at the science–science and science–policy interface in Finland, Sweden and Norway. It is based on document analysis and stakeholder questionnaires. The questionnaires targeted three stakeholder groups, all engaged in the communication and the use of climate scenario information: climate scenario producers; impact, adaptation and vulnerability (IAV) experts; and policy-makers. The respondents were asked to identify issues associated with the communication of scenarios and other needs pertaining to the usefulness and availability of such information. Despite the relatively long history of climate change adaptation in the three countries, climate scenarios are not utilised to their full potential. Climate scenarios have been used in awareness raising, problem understanding and strategy development. However, far less examples can be found on adaptation actions, particularly on harnessing the benefits of climate change. The communication between climate scenario producers and IAV experts functions well; however, communication between climate researchers and policy-makers is less efficient. Each country has developed boundary services to enhance dissemination of the climate scenario information to policy-makers. They are cost-efficient but do not necessarily enhance the comprehension of the information and encourage the actual dialogue between scenario producers and the end-users. Further translation of scenario information to impact and vulnerability estimates together with established boundary work could improve the use of climate research information. As adaptation policy in these countries further progresses towards implementation, there are increasing expectations of support from research, further challenging the communication of climate scenarios.  相似文献   
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