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481.
Antonio Roman-Alcalá 《Local Environment》2018,23(6):619-634
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
482.
Sofie Storbjörk Mattias Hjerpe Karolina Isaksson 《Journal of Environmental Policy & Planning》2018,20(1):81-95
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
483.
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
484.
Karoliina Pilli-Sihvola Bob van Oort Inger Hanssen-Bauer Markku Ollikainen Markku Rummukainen Heikki Tuomenvirta 《Local Environment》2015,20(4):510-524
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
485.
The sorption of carbamazepine (CBZ), iopromide (IOP), trimethoprim (TMP) and 17α-ethinylestradiol (EE2) was evaluated using four biomass types (pure ammonia oxidizing bacterial culture, two heterotrophic enrichment cultures with varying levels of oxygenase activity, and a full-scale nitrifying activated sludge (NAS) culture). CBZ and IOP did not sorb to the four biomass types. EE2 did not sorb to the pure culture but sorbed significantly to the heterotrophic cultures and NAS. TMP sorbed to the heterotrophic cultures and NAS, and was not evaluated for the pure culture. Three floc characteristics (hydrophobicity, median particle size, organic matter content) correlated moderately well with the EE2 organic matter sorption coefficient (KOM,EE2). Zeta potential did not correlate well with KOM,EE2 but did with KOM,TMP, indicating that TMP sorption is more influenced by electrostatic factors than EE2. Once divalent cation-linked exocellular polymeric substances (EPS) were removed from flocs, EE2 and TMP sorption to the non-EPS (cellular) fraction decreased by approximately 50%. The correlation between KOM,EE2 for the non-EPS cellular fraction deteriorated while the correlation between KOM,TMP improved. EE2 seemed to sorb more strongly to EPS protein whereas TMP sorbed equally to polysaccharide and protein EPS. Attempts to develop predictive models were not successful. Pharmaceuticals that sorbed to biomass samples underwent biodegradation whereas those that did not sorb were not biodegraded, suggesting a relationship between sorption and pharmaceutical biotransformation. 相似文献
486.
In the search for larvicidal compounds against Aedes aegypti L. (Diptera: Culicidae), a collection of monoterpenes were selected and evaluated. R- and S-limonene exhibited the highest larvicidal potency (LC50 = 27 and 30 ppm, respectively), followed by γ-terpinene (LC50 = 56 ppm) and RS-carvone (LC50 = 118 ppm). Structural characteristics which may contribute to the understanding of the larvicidal activity of monoterpenes were empirically identified. The presence of heteroatoms in the basic hydrocarbon structure decreases larvicidal potency. Conjugated and exo double bonds appear to increase larvicidal potency. Replacement of double bonds by more reactive epoxides decreases the larvicidal potency. The presence of hydroxyls in the cyclic structure resulted in decreased potency, probably due to increased polarity indicanting that lipophilicity seems to play an important role in increasing the larvicidal potency in this set of compounds. 相似文献
487.
Philopatry, male presence and grooming reciprocation among female primates: a comparative perspective 总被引:3,自引:0,他引:3
Competition for food and a safe location in a group are considered to be the main determinants of variation in social relationships
among female primates. The effect of the presence of males is usually overlooked, however. Here we put forward two hypotheses
connecting the (relative) number of males in a group, a statistic measuring the strength of positive relationships among females
(the degree of reciprocity of grooming) and female residence. Under the first hypothesis, we assumed that philopatric females
suffer especially from competition for males. Because females of these species are restrained to their native group and thus
do not move to groups where better conditions (i.e. more males) prevail, a higher socionomic sex ratio would imply reduced
competition and this should be reflected in better relationships among females (i.e. in a higher degree of reciprocation).
The second hypothesis is based on the contention of Wrangham (1987) that groups with more males are better able to defend
large food sources: in these groups female relationships would suffer less from within-group competition for food. We therefore
also expected a positive correlation between the absolute number of males and grooming reciprocation. To test the hypotheses,
matrices of grooming interactions were collected by going through the primatological literature. For ten female-resident and
four female-transfer primate species, the degree of grooming reciprocation was quantified using a specially adapted matrix
statistic. The results favoured the first (competition for males) hypothesis. The degree of grooming reciprocation among females
was positively correlated with socionomic sex ratio, but neither with group size nor with the absolute number of males. Correlations
between the degree of reciprocity and sex ratio were confirmed at three levels: within the same group at different points
in time, between groups of the same species, and between species. In addition, the degree of reciprocation increased with
sex ratio more strongly in typical single/variable male than in multi-male species. This we interpreted as a direct consequence
of the lower social availability of males for females in multi-male groups than single-male groups. In turn, this effect may
be due to males competing for females in multi-male groups.
Received: 28 May 1997 / Accepted after revision: 9 November 1997 相似文献
488.
Many land-use change studies have relied on geographical explanatory factors. Unfortunately, they are but a single perspective in the multidimensional process of human decision-making. This project was designed to model the social, economic, geographic, and regulatory factors at the most appropriate unit of analysis, the landowner. By examining parcelization, a window is opened into the antecedent event of land-use change. A logistic regression model determined the likelihood a tax parcel would split in three time periods between 1953 and 2007. Geographic variables showed expected relationships to a parcelization event, while economic and regulatory variables illustrated some unexpected relationships. Social variables demonstrated scale issues that challenged their efficacy. A temporal analysis showed that historic parcelization was explained more robustly than more contemporary parcelization. The results could indicate that contemporary parcelization is driven by new and more complex factors not yet represented in similar models. 相似文献
489.
This study reported the use of UV–visible and fluorescence spectroscopy and partial-least-square (PLS) multivariate regression for accurate and simultaneous quantifications of two widely used herbicides, propanil, 3′,4′-dichloropropionanilide (PPL) and bromoxynil, 3,5-dibromo-4-hydroxybenzonitrile (BXL) in human serum albumin (HSA) at physiological conditions. The binding affinity and thermodynamic properties of PPL-HSA and BXL-HSA complexes were also investigated. Partial-least-square (PLS) regression was used to collate the variability in the absorption or emission spectra of PPL-HSA and BXL-HSA complexes with PPL and/or BXL concentrations in HSA samples. The binding constants of 7.66× 108 M?1 for PPL-HSA and 4.88× 106 M?1 for BXL-HSA complexes were calculated at physiological conditions (temperature, 310 K; pH 7.4). Thermodynamic parameter values: enthalpy (ΔH) (13.99 kJ mol?1), entropy (ΔS) (0.078 kJ mol?1 K?1), and Gibbs free energy (ΔG) (?10.19 kJ mol?1) were determined for PPL-HSA complexation at physiological conditions. However, differences in thermodynamic property values of: ΔH (?214.3 kJ mol?1), ΔS (?0.563 kJ mol?1 K?1), and ΔG (?39.70 kJ mol?1) were observed for BXL–HSA complexes. The binding constants and negative ΔG values indicated strong binding affinity and thermodynamically favorability of PPL–HSA and BXL–HSA complex formation. Results of the PLS regression calibration showed good linearity (R2 ≥ 0.998289), high sensitivity, and impressive low limit-of-detections (LODs) of 1.38× 10?8 M for PPL and 1.68× 10?8 M for BXL that are comparable and/or lower than many previously reported LODs for herbicide and pesticide analyses. Most importantly, PLS regression is capable of simultaneous quantifications of PPL and BXL concentrations in HSA samples with good accuracy and low errors of 3.66%. UV–visible spectrophotometers and spectrofluorometers are fairly inexpensive, easy to use, and are readily available in almost every laboratory, making this protocol excellent and affordable for routine analysis of weed/pest control chemical residues in humans. The results of this study are significant and remarkable that will provide critical insight into the binding mechanism of herbicide toxicity in humans and non-target organisms, which are of special interest in the area of biomedical study, environmental risk assessment, and ecotoxicology. 相似文献
490.
Kakali Mukhopadhyay Xi Chen Paul Thomassin 《International Journal of Green Energy》2017,14(4):400-415
The Government of Canada has committed that Canada’s total greenhouse gas (GHG) emissions be reduced by 17% from 2005 levels by 2020. The new Renewable Fuels Regulations required 2% renewable content in diesel fuel and heating distillate oil and 5% for gasoline. This represents approximately 2.1 billion liters of ethanol and 600 million liters of biodiesel requirement per year, which would reduce GHG emissions by more than four million tones. Canada is expected to consume more fuel ethanol compared to its production capacity. The above mandates as well as the gap in consumption and production of biofuel will have enormous impact on the Canadian economy. In this backdrop, an input–output model of the Canadian economy is developed to estimate the macroeconomic impact of the ethanol and biodiesel production in Canada. The impacts on sectoral prices have also been calculated. Simulation exercises have been attempted to reach the mandates using modified Leontief model. Results show that agriculture sector is affected because of feedstock use in the biofuel sector. Mining and manufacturing industries also show a considerable impact. In addition, the impact on commodity prices cannot be ignored. Finally, to meet the target of Copenhagen commitment, the nation needs to revise the blending capacity of ethanol and biodiesel. 相似文献