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721.
Habituation to nonlethal predation stimuli may provide benefits for animals living in areas with frequent encounters with low-risk predators. On the other hand, individuals can be very consistent in their antipredator responses, with shy individuals showing greater degree of responsiveness than bold individuals. However, the link between habituation or boldness and individual benefits has not been thoroughly investigated. We established whether and how two behavioral components associated with antipredator responses (habituation and boldness, and their interaction) would influence body condition, which is a parameter related to fitness. We conducted an outdoor semi-natural experiment with Iberian wall lizards (Podarcis hispanica). Individual boldness was consistent across contexts, but we did not find any effect of boldness or the interaction between boldness and habituation on body condition. However, those individuals that habituated more readily to a frequent predatory stimulus were able to increase their body condition more relative to lizards that habituated less. This finding highlights the importance of individual differences in behavioral plasticity, which could influence traits related to fitness. Habituation can provide benefits for individuals exposed to low-risk predators; however, individuals more prone to habituation could also experience mortality costs by wrongly habituating to a dangerous predator.  相似文献   
722.
723.
Phthalates are animal carcinogens and may cause death or tissue deformities. Samples of feedstuffs collected in 2005 and 2006 from industrial feed manufacturers in the Czech Republic were analysed for contamination with phthalic acid esters (PAEs), specifically di-2-ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DBP). Samples of feed additives, premixes and raw materials were collected (year 2005, n = 26). For soybean oil, the total volume of phthalates measured (DBP + DEHP) reached a level of 131.42 mg kg−1; for rapeseed oil, fish meal and animal fats, the levels measured were 15.00, 7.96 and 58.87 mg kg−1, respectively. The lowest level of DBP + DEHP was found in corn (2.03 mg kg−1). Since phthalates were detected, samples of feed additives (n = 28) and raw materials (n = 28) were collected again in 2006. The highest levels of DBP + DEHP were found in raw materials containing fat. Phthalate levels in rapeseed oil samples ranged from 1.38 to 32.40 mg kg−1 DBP + DEHP. For feed additives, contamination levels in vitamins and amino acids ranged from 0.06 to 3.15 and 1.76 to 4.52 mg kg−1 DBP + DEHP, respectively. Here, we show that the levels of PAEs found in cereals such as wheat, barley and corn may be regarded as being alarmingly high, because cereals make up the largest proportion of compound feed of farm animals.  相似文献   
724.
Journal of Material Cycles and Waste Management - The problem of food waste is broadly discussed, but empirical data are still missing. The importance of this topic increases as the reporting of...  相似文献   
725.
726.
An approach to reduce the probability of producing a domino effect in process industry is developed in this work. It is assumed that optimal layouts should include appropriate analysis to reduce risk during the process design stage. The model developed for this approach combines the estimation of probability of damage due to overpressure, proposed by Mingguang and Juncheng (2008), and escalation threshold values defined by Cozzani, Gubinelli, and Salzano (2006). These equations are combined with other typical layout constraints as well as bounding the probability constraint, which has resulted in a highly non-linear MINLP problem. Solving a case study used by other authors provides evidence for reliability of the developed approach. In this way, layouts are designed to reduce the escalation probability yielding safe distributions.  相似文献   
727.
Invoking expert knowledge is a common strategy in attempts to settle environmental disputes. However, the validity of expertise is contingent upon the context in which an actor is recognised as an expert. In complex environmental conflicts the distinction between lay and expert knowledge is not always fixed a priori. However, as conflicts unfold, intervening parties tend to present their cases in ways that reinforce this distinction. This is apparent in the attribution of environmental responsibilities. This paper presents an empirical case of an environmental conflict related to land contamination due to coal ash disposal in Bosnia and Herzegovina. The analysis revealed two polar positions in the conflict: the first one, mainly held by scientists and industry representatives, invoked expert knowledge and presented a distributed approach to the attribution of responsibilities; the second one, mainly held by local residents and municipal officials, presented an experiential understanding of pollution, as lay knowledge, and attributed direct responsibilities to the local energy industry. The paper concludes that the persistence of the distinction between expert and lay knowledge is a manifestation of the social structures that underlie the conflict.  相似文献   
728.
ABSTRACT

Extent and distribution of urban green spaces (UGS) in Mazatlan (Mexico) are analysed using remote sensing and GIS techniques. Vegetated areas (2,270?ha), a third of the urban area in 2015, were reclassified into green spaces (GS), urban tree (UT) and open spaces (OS), based in the normalised difference vegetation index, relating them with demographic and socioeconomic data. UGS allocation per capita amount 55?m2, mainly represented by the UT class, with the largest patches associated with low developed and very high marginalised areas, and also with very low marginalised sectors, while the lowest allocation correspond to medium and low marginalisation, highly populated sector, without significant correlations. Despite the USG allocation, it is required a better urban planning to maintain public UGS and to protect the local flora, threatened by the introduction of exotic, ornamental species (64% of UT), to guarantee the provision of ecosystem services to the population.  相似文献   
729.
As new forms of governance for climate change emerge in African cities, will they enable emancipatory and socially progressive transformations or will they exacerbate existing inequality, poverty and vulnerability patterns? This paper presents one of the case studies developed by UN-Habitat Cities and Climate Change Initiative in Maputo, Mozambique. The case analyses first, the production of urban vulnerabilities under climate change, and second, the existing governance arrangements for climate change in the city. Building on the lessons of the case study, the paper argues that to ensure that new forms of climate change governance lead to socially and environmentally just outcomes climate change interventions should, at least, meet two conditions: first, they should consider the close interactions between social and ecological elements and, specially, how patterns of urban inequality interact with environmental factors; second, they should recognise the opportunities in African cities through a broad notion of governance that looks beyond the government as the sole agent of urban change.  相似文献   
730.
Recent research has explored the role of environmental inequalities in explaining health disparities, especially in urban environments. This paper investigates the role of the landlord in shaping indoor environmental injustices. Specifically, we rely on interview data from low-income parents in South Phoenix, AZ, with elementary-aged children with asthma. We found families living in poor quality rental housing that impacted children's breathing. Landlords were directly involved in keeping the homes in poor condition, even when asked by the tenant to fix the property, and immigrants were especially at risk. In general, relationships between landlords and tenants were unequal and coloured by the tenant's poverty and fears of eviction. Among the immigrant tenants, many had accompanying fears of authorities and deportation. The cycle of fear, poverty, and a lack of power compounded as tenants were hesitant to report problems, which reinforced the power of the landlord over the tenant and did nothing to improve living conditions. Recognising the role of landlords in creating substandard housing conditions is important as they represent a group that can be targeted for interventions.  相似文献   
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