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New spaces of food justice
‘Food is fundamental to life’ (Sbicca 2012, 456) and this shared need establishes food as a site of potential for connective and convivial practices and relations. Yet, when we realise that more than one billion people are undernourished worldwide (Food Ethics Council 2010), despite the fact that the world produces enough food to feed billions more than the current global population of seven billion (Holt-Gimenez et al. 2012), the social, political, economic and environmental challenges posed by contemporary food systems start to become apparent. Given current global production levels – whether we agree with the social and environmental implications of these or not – it is clear that malnutrition rates worldwide are not simply an indicator of agricultural praxis but demonstrate the continued, broader social and structural issues of access, equity and justice. Recognising that many feel increasingly disenfranchised from formal political representation, marginalised by a hegemonic neoliberal capitalism or disconnected from ‘healthy’ social or environmental relations, food offers an opportunity to re-engage individuals and society with critical questions and practices of justice because, as Allen (2008, 159) notes, ‘no other public issue is as accessible to people in their daily lives as that of food justice. Everyone – regardless of age, gender, ethnicity, or social class – eats. We are all involved and we are all implicated’. The multiplicity of ways in which we can engage with food – including growing, buying, eating, cooking, writing, processing, marketing, selling and watching – enacts its radical potential as a set of dynamic socio-material relations (Alkon 2013; Alkon et al. 2013) that can both conform to and subvert existing practices and understandings, enabling food to ‘speak’ to many different people in a range of different contexts. Although this multiplicity has its dangers (Heynen, Kurtz, and Trauger 2012), it also means that food matters and matters in complex and diverse ways: ‘It rallies people and it often induces unexpected changes in society’ (Van der Ploeg 2013, 999)
Multigrid Method versus Staging Algorithm for PIMC Simulations
We present a comparison of the performance of two non-local update algorithms
for path integral Monte Carlo (PIMC) simulations, the multigrid Monte Carlo
method and the staging algorithm. Looking at autocorrelation times for the
internal energy we show that both refined algorithms beat the slowing down
which is encountered for standard local update schemes in the continuum limit.
We investigate the conditions under which the staging algorithm performs
optimally and give a brief discussion of the mutual merits of the two
algorithms.Comment: 11 pp. LaTeX, 4 Postscript Figure
Test of variational approximation for quantum chain by Monte Carlo simulation
We report results of a Monte Carlo simulation of the quantum chain.
In order to enhance the efficiency of the simulation we combine multigrid
simulation techniques with a refined discretization scheme. The resulting
accuracy of our data allows for a significant test of an analytical
approximation based on a variational ansatz. While the variational
approximation is well reproduced for a large range of parameters we find
significant deviations for low temperatures and large couplings.Comment: 12 pp. Latex + 3 figures as uuencoded compressed tar file, accepted
for publication in Phys. Lett.
Inactivation of the DNA-repair gene MGMT and the clinical response of gliomas to alkylating agents
Background: the DNA-repair enzyme O6-methylguanine-DNA methyltransferase (MGMT) inhibits the killing of tumor cells by alkylating agents. MGMT activity is controlled by a promoter; methylation of the promoter silences the gene in cancer, and the cells no longer produce MGMT. We examined gliomas to determine whether methylation of the MGMT promoter is related to the responsiveness of the tumor to alkylating agents. Methods: we analyzed the MGMT promoter in tumor DNA by a methylation-specific polymerase-chain-reaction assay. The gliomas were obtained from patients who had been treated with carmustine (1,3-bis(2-chloroethyl)-1-nitrosourea, or BCNU). The molecular data were correlated with the clinical outcome. Results: the MGMT promoter was methylated in gliomas from 19 of 47 patients (40 percent). This finding was associated with regression of the tumor and prolonged overall and disease-free survival. It was an independent and stronger prognostic factor than age, stage, tumor grade, or performance status. Conclusions: methylation of the MGMT promoter in gliomas is a useful predictor of the responsiveness of the tumors to alkylating agents
Reductions in cardiovascular, cerebrovascular, and respiratory mortality following the national Irish smoking ban: Interrupted time-series analysis
Copyright @ 2013 Stallings-Smith et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.This article has been made available through the Brunel Open Access Publishing Fund.Background: Previous studies have shown decreases in cardiovascular mortality following the implementation of comprehensive smoking bans. It is not known whether cerebrovascular or respiratory mortality decreases post-ban. On March 29, 2004, the Republic of Ireland became the first country in the world to implement a national workplace smoking ban. The aim of this study was to assess the effect of this policy on all-cause and cause-specific, non-trauma mortality. Methods: A time-series epidemiologic assessment was conducted, utilizing Poisson regression to examine weekly age and gender-standardized rates for 215,878 non-trauma deaths in the Irish population, ages ≥35 years. The study period was from January 1, 2000, to December 31, 2007, with a post-ban follow-up of 3.75 years. All models were adjusted for time trend, season, influenza, and smoking prevalence. Results: Following ban implementation, an immediate 13% decrease in all-cause mortality (RR: 0.87; 95% CI: 0.76-0.99), a 26% reduction in ischemic heart disease (IHD) (RR: 0.74; 95% CI: 0.63-0.88), a 32% reduction in stroke (RR: 0.68; 95% CI: 0.54-0.85), and a 38% reduction in chronic obstructive pulmonary disease (COPD) (RR: 0.62; 95% CI: 0.46-0.83) mortality was observed. Post-ban reductions in IHD, stroke, and COPD mortalities were seen in ages ≥65 years, but not in ages 35-64 years. COPD mortality reductions were found only in females (RR: 0.47; 95% CI: 0.32-0.70). Post-ban annual trend reductions were not detected for any smoking-related causes of death. Unadjusted estimates indicate that 3,726 (95% CI: 2,305-4,629) smoking-related deaths were likely prevented post-ban. Mortality decreases were primarily due to reductions in passive smoking. Conclusions: The national Irish smoking ban was associated with immediate reductions in early mortality. Importantly, post-ban risk differences did not change with a longer follow-up period. This study corroborates previous evidence for cardiovascular causes, and is the first to demonstrate reductions in cerebrovascular and respiratory causes
Genome dynamics in major bacterial pathogens
Pathogenic bacteria continuously encounter multiple forms of stress in their hostile environments, which leads to DNA damage. With the new insight into biology offered by genome sequences, the elucidation of the gene content encoding proteins provides clues toward understanding the microbial lifestyle related to habitat and niche. Campylobacter jejuni, Haemophilus influenzae, Helicobacter pylori, Mycobacterium tuberculosis, the pathogenic Neisseria, Streptococcus pneumoniae, Streptococcus pyogenes and Staphylococcus aureus are major human pathogens causing detrimental morbidity and mortality at a global scale. An algorithm for the clustering of orthologs was established in order to identify whether orthologs of selected genes were present or absent in the genomes of the pathogenic bacteria under study. Based on the known genes for the various functions and their orthologs in selected pathogenic bacteria, an overview of the presence of the different types of genes was created. In this context, we focus on selected processes enabling genome dynamics in these particular pathogens, namely DNA repair, recombination and horizontal gene transfer. An understanding of the precise molecular functions of the enzymes participating in DNA metabolism and their importance in the maintenance of bacterial genome integrity has also, in recent years, indicated a future role for these enzymes as targets for therapeutic intervention
Suggested Improvements for the Allergenicity Assessment of Genetically Modified Plants Used in Foods
Genetically modified (GM) plants are increasingly used for food production and industrial applications. As the global population has surpassed 7 billion and per capita consumption rises, food production is challenged by loss of arable land, changing weather patterns, and evolving plant pests and disease. Previous gains in quantity and quality relied on natural or artificial breeding, random mutagenesis, increased pesticide and fertilizer use, and improved farming techniques, all without a formal safety evaluation. However, the direct introduction of novel genes raised questions regarding safety that are being addressed by an evaluation process that considers potential increases in the allergenicity, toxicity, and nutrient availability of foods derived from the GM plants. Opinions vary regarding the adequacy of the assessment, but there is no documented proof of an adverse effect resulting from foods produced from GM plants. This review and opinion discusses current practices and new regulatory demands related to food safety
Value of eight-amino-acid matches in predicting the allergenicity status of proteins: an empirical bioinformatic investigation
The use of biotechnological techniques to introduce novel proteins into food crops (transgenic or GM crops) has motivated investigation into the properties of proteins that favor their potential to elicit allergic reactions. As part of the allergenicity assessment, bioinformatic approaches are used to compare the amino-acid sequence of candidate proteins with sequences in a database of known allergens to predict potential cross reactivity between novel food proteins and proteins to which people have become sensitized. Two criteria commonly used for these queries are searches over 80-amino-acid stretches for >35% identity, and searches for 8-amino-acid contiguous matches. We investigated the added value provided by the 8-amino-acid criterion over that provided by the >35%-identity-over-80-amino-acid criterion, by identifying allergens pairs that only met the former criterion, but not the latter criterion. We found that the allergen-sequence pairs only sharing 8-amino-acid identity, but not >35% identity over 80 amino acids, were unlikely to be cross reactive allergens. Thus, the common search for 8-amino-acid identity between novel proteins and known allergens appears to be of little additional value in assessing the potential allergenicity of novel proteins
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