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571.
Despite their opposition to the dominant agri-food system, alternative agri-food initiatives may unwittingly reproduce central features of neoliberalism. Julie Guthman has been a particularly strong proponent of this view, arguing that food activism and neoliberalism have shaped one another dialectically in California in recent decades. This paper responds to her argument, with a view to distinguishing between what it reveals and what it may conceal about the transformative potential of alternative agri-food initiatives in North America. Drawing on primary research on a variety of community-based food initiatives in Eastern Ontario, Canada, we show how a neoliberal lens does help to illuminate some problematic characteristics of these initiatives, including assumptions about market-based solutions and focus on self-improvement at the expense of state involvement. However, this lens underestimates those aspects of community-based food initiatives that may appear commensurate with neoliberal rationalities but which also push in more progressive directions. 相似文献
572.
OBJECTIVE: Smoking has been linked to disease and injury. The purpose of this study is to investigate the smoking habits of motor vehicular driver trauma center patients and their association with previous injury history and risky behaviors. METHODS: The studied population included 323 motor vehicular driver injury patients (123 smokers and 200 non-smokers) interviewed as part of a larger study of psychoactive substance use disorders at an adult Level I trauma center. Patients with head injuries, hospital stays of less than two days, and diminished cognition were excluded. Interviews included demographics (age, gender, race, marital status), socioeconomic status (SES; income, education, employment), risky behaviors (seatbelt non-use, drinking and driving, riding with drunk driver, binge drinking), and trauma history information (vehicular, assault, and other injuries). Substance abuse (alcohol and drug dependence) was evaluated in depth using DSM III-R criteria. Smokers and non-smokers were compared in relation to control and dependent variables using student's t test and chi-square (alpha = 0.05). Outcome variables included previous trauma history and risky behaviors. Multiple logistic regression models using step-down selection methods (alpha = 0.05) were constructed with risky behaviors and trauma history as dependent variables including demographics, SES and substance as independent variables. RESULTS: Smokers represented 38 percent of the 323 patients studied. Smokers (n = 123) were younger (34 vs. 43 years), more likely to be male (72 percent vs. 50 percent), not married (72 percent vs. 56 percent), and had higher rates of alcohol (29 percent vs. 9 percent) and drug dependence (14 percent vs. 3 percent) than non-smokers (n = 200). Educational achievement (20 percent vs. 15 percent less than high school) and income level (24 percent vs. 23 percent with less than $15,000 of yearly income) were not different between smokers and non-smokers. Smokers were more likely than non-smokers to have a history of prior vehicular trauma (48 percent vs. 26 percent), assault (25 percent vs. 9 percent), or other injury (50 percent vs 37 percent). The following injury-prone behaviors were also more common among the smokers than non-smokers: seatbelt non-use (49 percent vs. 29 percent), drinking and driving (38 percent vs. 15 percent), riding with drunk driver (38 percent vs. 13 percent), and binge drinking (68 percent vs. 26 percent). In multiple logistic regression models adjusting for demographics, SES, and substance abuse, smoking revealed significantly higher odds ratios (OR) for the following dependent variables: seatbelt non-use (OR = 2.9), riding with drunk driver (OR = 2.2), binge drinking (OR = 2.4), previous vehicular (OR = 2.0), and assault injuries (OR = 2.5). Smoking did not reach significance for drinking and driving and other (non-vehicular and non-assault) injury. CONCLUSION: Smoking is independently associated with risky behaviors and repeated history of vehicular or assault injury within the vehicular trauma population. 相似文献
573.
Adriana E. Downie Lukas Van Zwieten Ronald J. Smernik Stephen Morris Paul R. Munroe 《Agriculture, ecosystems & environment》2011,140(1-2):137-147
Soils developed on the sites of Australian Aboriginal oven mounds along the Murray River in SE Australia, classified as Cumulic Anthroposols under the Australian Soil Classification, are shown to have traits similar to the Terra Preta de Indio of the Amazon basin. Seven such sites were characterised and compared with adjacent soils. The Cumulic Anthroposols contained significantly (p < 0.05) more soil carbon (C), compared to adjacent non-Anthroposols. Solid-state 13C NMR spectroscopy showed that the C in the Cumulic Anthroposols was predominantly aromatic, especially at depth, confirming the presence of charcoal. Radiocarbon analysis carried out on charcoal collected from two of these sites showed that it was deposited 650 ± 30 years BP at one site and 1609 ± 34 years BP at the other site, demonstrating its recalcitrance in soil. The charcoal originated from plant material, as shown by SEM, and had high levels of Ca agglomeration on its surfaces. The Cumulic Anthroposols were shown to have altered nutrient status, with total N, P, K and Ca being significantly greater than in the adjacent soils throughout the profile. This was also reflected in the higher mean CEC of 31.2 cmol (+) kg?1 and higher pH by 1.3 units, compared to the adjacent soils. Based on the similarity of these Cumulic Anthroposols with the Terra Preta de Indio of the Amazon, we suggest that these Cumulic Anthroposols can be classified as Terra Preta Australis. The existence of these soils demonstrates that Australian soils, in temperate climates, are capable of storing C in much higher quantities than has been previously recognised, and that this capability is founded on the unique stability and properties of charred organic matter. Furthermore, the addition of charcoal appears to have improved the physical and chemical properties of these soils. Together, this provides important support for the concept of soil amendment with “biochar”, the charred residue produced by pyrolysis of biomass, as a means for sequestering C and enhancing agricultural productivity. 相似文献
574.
Marina Medvedova Adriana Kolesarova Marcela Capcarova Roman Labuda Alexander V. Sirotkin Jaroslav Kovacik 《Journal of environmental science and health. Part. B》2013,48(3):213-219
The aim of this in vitro study was to examine the secretion activity, markers of proliferation and apoptosis in porcine ovarian granulosa cells (GCs) after deoxynivalenol (DON) addition. Ovarian granulosa cells were incubated with DON for 24h: 10, 100 and 1000 ng/mL, while the control group received no DON. The secretion of insulin-like growth factor I (IGF–I) and progesterone was determined by radioimmunoassay (RIA) and expression of cyclin B1, PCNA and caspase-3 by immunocytochemistry. IGF–I release by GCs was inhibited by DON, while progesterone release and the expression of cyclin B1 was stimulated by DON (at 1000 ng/mL but not at 10 and 100 ng/mL). PCNA expression was stimulated by DON (at 100 and 1000 ng/mL but not at 10 ng/mL). Caspase-3 expression was not influenced by DON treatment (at all doses). In conclusion, our results indicate, (1) a direct effect of DON on secretion of growth factor IGF-I and steroid hormone progesterone, (2) expression of markers of proliferation (cyclin B1 and PCNA) but not on the (3) expression of marker of apoptosis (caspase-3) in porcine ovarian granulosa cells. This in vitro study suggests the dose-dependent association of DON on porcine ovarian functions. 相似文献
575.
José Gianottp Guillermo Stettler Ernesto Haggp Adriana Pajares Sonia G. Bertolotti Norman A. García 《毒物与环境化学》2013,95(3-4):461-470
Nonylphenol (nonyl‐P) belongs to the classification of persistent organic pollutants. In this work we demonstrate that the contaminant suffers photooxygenation when exposed to visible light Eosin‐photosensitized irradiation. The mechanism was identified as a singlet molecular oxygen‐mediated photooxidation. Rate constants for the process, determined by time‐resolved phosphorescence detection of singlet molecular oxygen, are in the range 105‐107 M‐1 s‐1, depending on the characteristics of the reaction medium. The photooxidative process is more efficient when performed in highly polar alkaline medium. The aggregation of nonyl‐P molecules in pure water decreases the rates of sensitized photooxidation of nonyl‐P and also those of polychlorophenolic contaminants, employed as photooxidizable model compounds, when photolyzed in the presence of nonylphenol. These results are discussed in terms of a micellar effect. 相似文献
576.
Patricia Miretzky Carolina Mu?oz Enrique Cantoral-Uriza 《Environmental Chemistry Letters》2011,9(1):55-63
Naturally occurring diatomaceous earth was modified by alkaline pretreatment, and its effectiveness for Cd2+ removal from contaminated water was investigated. Batch experiments were carried out to determine Cd2+ adsorption capacity and the efficiency of the sorption process under different experimental conditions. Experimental data
showed good fitting to Langmuir and Freundlich isotherms models. The Cd2+ maximum adsorption capacity was 0.058 mmol g−1 for raw diatomite and increased to 0.195 mmol g−1 for alkaline-pretreated diatomite with efficiency higher than 96% (diatomite dose 2.5 g L−1, pH 6). Adsorption of Cd2+ to alkaline-pretreated diatomite increased as the temperature increased. Thermodynamic parameters were calculated to evaluate
the feasibility of the adsorption process at different temperatures. The adsorption process was spontaneous and endothermic.
The interaction between Cd2+ ions and diatomite surface was weak enough to be considered as physical sorption, confirmed by the low value of activation
energy. 相似文献
577.
Patricia Palma Paula Alvarenga Vera L. Palma Rosa Maria Fernandes Amadeu M. V. M. Soares Isabel Rita Barbosa 《Environmental monitoring and assessment》2010,165(1-4):539-552
Multivariate statistical techniques were applied to evaluate spatial/temporal variations, and to interpret water quality data set obtained at Alqueva reservoir (south of Portugal). The water quality was monitored at nine different sites, along the water line, over a period of 18 months (from January 2006 to May 2007) using 26 water quality parameters. The cluster analysis allowed the formation of five different similarity groups between sampling sites, reflecting differences on the water quality at different locations of the Alqueva reservoir system. The PCA/FA identified six varifactors, which were responsible for 64% of total variance in water quality data set. The principal parameters, which explained the variability of quality water, were total phosphorus, oxidability, iron, parameters that at high concentrations indicate pollution from anthropogenic sources, and herbicides indicative of an intensive agricultural activity. The spatial analysis showed that the water quality was worse in the north of the reservoir. 相似文献
578.
Branislav Igic David R. Greenwood David J. Palmer Phillip Cassey Brian J. Gill Tomas Grim Patricia L. R. Brennan Suzanne M. Bassett Phil F. Battley Mark E. Hauber 《Chemoecology》2010,20(1):43-48
The known chemical basis of diverse avian eggshell coloration is generated by the same two classes of tetrapyrrole pigments
in most living birds. We aimed to extend the evolutionary scope of these patterns by detecting pigments from extinct birds’
eggs. In our samples biliverdin was successfully extracted from subfossil shell fragments of the blue-green egg-laying upland
moa Megalapteryx didinus, while protoporphyrin was extracted from the beige eggs of two other extinct moa species. Our data on pigment detection from
eggshells of other extant paleognath birds, together with published information on other modern lineages, confirm tetrapyrroles
as ubiquitous and conserved pigments contributing to diverse eggshell colours throughout avian evolution. 相似文献
579.
Richard FrankMartin A. Andresen Patricia L. Brantingham 《Journal of environmental psychology》2012,32(1):37-42
Spatial criminology has three interrelated elements: place, distance, and direction. Though directionality has had theoretical support for many years, very few empirical verifications of this component of crime have emerged. In this article, we investigate the strength of directionality by comparing a simulated randomized dataset and a large incident-based dataset of repeat offenders. We find strong evidence for a strong presence of directionality in criminal spatial decision-making. This aspect of the spatiality of crime must be considered in any attempts to understand the aetiology of crime. 相似文献
580.
Venera Ferrito Anna Maria Pappalardo Adriana Canapa Marco Barucca Ignacio Doadrio Ettore Olmo Concetta Tigano 《Marine Biology》2013,160(12):3193-3208
We studied the genetic structure of the Mediterranean killifish Aphanius fasciatus. Analysis of the sequence variation in a 372-bp portion of the mitochondrial control region in 623 fish from 27 sampling sites along the species’ distributional range (Tyrrhenian coast, Sardinia, Sicily, Adriatic coast, Malta, Tunisia, and Greece) yielded 120 distinct haplotypes. Most of the haplotypes are unique, and only 15 % are shared among different populations. The high F ST value (=0.80) suggests a strong population genetic structuring. The phylogenetic analysis based on Bayesian inference, maximum likelihood and maximum parsimony, and the median-joining network show a sharp separation of the Southeastern Sicilian populations (belonging to the Hyblean region) and of the fluvial Tunisian population of Rio Melah from the others. The Adriatic, the Eastern Sicilian, and the Greek populations are well differentiated, while the group of populations from the Central-Western Mediterranean does not show a clear pattern of differentiation. Our findings indicate that the current genetic structuring of A. fasciatus reflects historical geographical patterns occurring within the Mediterranean basin from the Late Miocene to the Pleistocene. The presence of divergent evolutionary entities in the Hyblean region and the Tunisian Rio Melah supports their inclusion as target areas for the conservation of A. fasciatus. 相似文献