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31.
In March of 2012, following a robust activist campaign, Arysta LifeScience withdrew the soil fumigant methyl iodide from the US market, just a little over a year after it had finally been registered for use in California. As a major part of the campaign against registration of the chemical, over 53,000 people, ostensibly acting as citizens rather than consumers, wrote public comments contesting the use of the chemical for its high toxicity. Although these comments had marginal impact on the outcome of the case, these comments are of interest for what they say about public action at a time when efforts to address food and agricultural issues have been dominated by “voting with your fork.” Based on a qualitative textual analysis of approximately 3500 representative comments made available to us, we show that many of those taking action did not abandon consumer subjectivities associated with neoliberal governmentality. By threatening “personal boycotts,” some were acting in their capacity as individual consumers; in invoking their own and their children’s health many more were also acting on behalf of consumers, despite that the chemical in question is applied before strawberries are planted and thus leaves no residues. The emphasis that letter writers gave to their own bodies reinforces the idea that some bodies count more than others and thus reveals a biopolitical sorting. Having consumer lives matter is consequential in light of evidence that consumer concern about pesticides has historically led to formulations and regulations more protective of consumers than workers and neighbors. 相似文献
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Sandy Adriaenssens Jeroen Staelens Karen Wuyts An de Schrijver Shari Van Wittenberghe Tatiana Wuytack Fatemeh Kardel Kris Verheyen Roeland Samson Pascal Boeckx 《Water, air, and soil pollution》2011,219(1-4):43-57
This study assessed the foliar uptake of 15N-labelled nitrogen (N) originating from wet deposition along with leaf surface conditions, measured by wettability and water storage capacity. Foliar 15N uptake was measured on saplings of silver birch, European beech, pedunculate oak and Scots pine and the effect of nitrogen form (NH 4 + or NO 3 ? ), NH 4 + to NO 3 ? ratio and leaf phenology on this N uptake was assessed. Next to this, leaf wettability and water storage capacity were determined for each tree species and phenological stage, and the relationship with 15NH 4 + and 15NO 3 ? uptake was examined. Uptake rates were on average five times higher (p?<?0.05) for NH 4 + than for NO 3 ? and four times higher for deciduous species than for Scots pine. Developing leaves showed lower uptake than fully developed and senescent leaves, but this effect was tree species dependent. The applied NH 4 + to NO 3 ? ratio did only affect the amount of N uptake by senescent leaves. The negative correlation between measured leaf contact angles and foliar N uptake demonstrates that the observed effects of tree species and phenological stage are related to differences in leaf wettability and not to water storage capacity. 相似文献
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Érica Camila G. Praxedes Gabriela L. Lima Andréia M. da Silva Lívia B. Campos Carla Michelle P. de Souza Samara Sandy J. Moreira Moacir F. de Oliveira Alexandre R. Silva 《Reproduction in domestic animals》2020,55(2):154-161
In contributing to the conservation of wild rodents, the aim of this study was to evaluate the use of distinct cryoprotectants, separately or in combination, for solid surface vitrification (SSV) of red-rumped agouti ovarian tissue. Ovarian cortex from nine females was recovered and fragmented. Fresh fragments (control) were used to analyse the pre-antral follicle (PF) morphology using a histologic procedure, viability using the Trypan blue test, cell proliferation by counting the argyrophilic nucleolar organizing regions (Ag-NORs technique) and DNA integrity using the TUNEL assay. The remaining fragments were vitrified using SSV method with 3 M or 6 M ethylene glycol (EG) or dimethyl sulfoxide (DMSO), or in combination (3 M EG/3 M DMSO), and further evaluated as reported for the fresh samples. All cryoprotectants were effective at preserving PFs morphology compared to the control group (80.7 ± 5.21%), except 6 M EG and 3 M DMSO that provoked a significant (p < .05) decrease on the values of morphologically normal primary (60.0 ± 19.0%) and primordial (44 ± 4.5%) follicles, respectively. Regarding viability, all cryoprotectants provided values similar to that verified for the control group (79.0%), but a significant decrease (p < .05) was observed with EG/DMSO combination (59%). Using Ag-NORs technique, the highest (p < .05) cell proliferative capacity was detected when using EG at each tested concentration. The TUNEL proved the preservation of DNA integrity regardless of the cryoprotectant. In summary, we suggest the use of 3 M EG for the solid surface vitrification of red-rumped agouti ovarian tissue. 相似文献
34.
David Pink Liz Bailey Sandy McClement Paul Hand Evy Mathas Vicky Buchanan-Wollaston Dave Astley Graham King Graham Teakle 《Euphytica》2008,164(2):509-514
Double haploid (DH) plants of Brassica spp. can be produced via anther culture or culture of microspores. This paper reviews the uses of double haploids in crop
improvement research in vegetable brassicas (B. oleracea). Applications of DH lines are described for breeding; construction of linkage maps; genetic analysis of quantitative traits
and capturing genetic variation. The advantages and disadvantages of DH lines are discussed 相似文献
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BACKGROUND: The potential development of resistance to Bacillus thuringiensis (Bt) cotton and surging of non‐targeted insects is a major risk in the durability of Bt plant technology. Midgut proteinases are involved in Bt activation and degradation. Proteinase inhibitors may be used to control a wide range of insects and delay Bt resistance development. Proactive action to examine proteinase inhibitors for synergistic interaction with Bt toxin and cloning of proteinase cDNAs for RNAi is necessary to make transgenic cotton more versatile and durable. RESULTS: A sublethal dose (15 ppb) of Cry1Ac, 0.5% benzamidine and 0.02% phenylmethylsulfonyl fluoride significantly suppressed midgut azocaseinase, tryptic and chymotryptic activities, and resulted in reductions in larval and pupal length and mass of Heliothis virescens. The combination of proteinase inhibitor and Bt suppressed 20–37% more larval body mass and 26–80% more enzymatic activities than the inhibitor only or Bt only. To facilitate knockdown‐resistance‐related proteinase genes, 15 midgut chymotrypsin cDNAs were sequenced. Most predicted chymotrypsins contained the conserved N‐termini IVGG, three catalytic center residues (His, Asp and Ser), substrate specificity determinant (Ser or Gly) and cysteines for disulfide bridges. These putative chymotrypsins were separated into three distinct groups, indicating the diverse proteinases evolved in this polyphagous insect. CONCLUSION: H. virescens has evolved diverse midgut proteinase genes. Proteinase inhibitors have potential insecticidal activity, and the interaction of Bt with proteinase inhibitors is desirable for enhancing Bt toxicity and delaying resistance development. Intensive sequencing of chymotrypsin cDNAs will facilitate future functional examinations of individual roles in Bt toxicity and resistance development and facilitate targeted control using RNAi and/or proteinase inhibitors. Copyright © 2012 Society of Chemical Industry 相似文献
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Descamps FF Brouta F Vermout SM Willame C Losson BJ Mignon BR 《Veterinary dermatology》2003,14(6):305-312
A Microsporum canis recombinant 31.5 kDa keratinase and a M. canis crude exo-antigen were tested as vaccines in an experimental infection model in guinea pigs. Animals were vaccinated subcutaneously three times at two-week intervals with either the keratinase, the exo-antigen or the adjuvant alone. Cutaneous challenge was performed blindly. Both humoral and cellular-specific immune responses to M. canis antigens were evaluated every 14 days, while a blind evaluation of clinical lesion development and fungal persistency in skin were monitored weekly. Vaccination induced very high and significant (P < 0.01) antibody responses towards both antigens. High cell-mediated immune responses to both immunogens were also induced by vaccination. After challenge, however, scores reflecting the severity of dermatophytic lesions did not differ significantly between vaccinated and control groups at any time after challenge. These results suggest that, in the guinea pig, the induction of specific immune responses against the M. canis-secreted antigens used in this study are not protective against challenge exposure. 相似文献
40.
Antimicrobial susceptibility of hazard analysis critical control point Escherichia coli isolates from federally inspected beef processing plants in Alberta, Saskatchewan, and Ontario
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Van Donkersgoed J Manninen K Potter A McEwen S Bohaychuk V Klashinsky S Deckert A Irwin R 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(9):723-728
A survey to estimate the prevalence of antimicrobial resistance in Escherichia coli was conducted in 7 Canadian federally inspected processing plants during 2001. Escherichia coli isolates were recovered during routine hazard analysis critical control point sampling from beef carcasses and trim and subsequently tested for their antimicrobial susceptibility by using susceptibility panels. Of the 2653 isolates analyzed, 68% were sensitive to all 18 antimicrobials tested. For 14 of the 18 antimicrobials evaluated, the percentage of resistant isolates was < or = 1. Twenty-five percent of the isolates were resistant to tetracycline, 9% to sulfamethoxazole, 7% to streptomycin, and 3% to ampicillin. Multiple resistance was found in 12% of the isolates, with 7% showing resistance to 2 antimicrobials, 2% to 3 antimicrobials, 2% to 4 antimicrobials, and 1% to 5 or more antimicrobials. Forty-five different antimicrobial resistance patterns were observed. The reasons for the development of the antimicrobial resistance were not investigated in this study. This study was useful as a pilot to help to develop a national antimicrobial resistance surveillance program in Canada. This study indicates that laboratory standardization is possible for consistent results across the country and that the indicator organism, E. coli, is fairly easy to obtain for surveillance but Salmonella are not, due to their low prevalence in beef. 相似文献