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41.
As concerns heighten over links between biomass production and land grabs in the global south, attention is turning to understanding the role of governance of biofuels systems, whereby decision-making and conduct are not solely determined through government regulations but increasingly shaped by non-state actors, including multi-stakeholder initiatives (MSI). Launched in 2005, Bonsucro is the principal MSI that focuses on sustainability standards for sugar and sugarcane ethanol production. Bonsucro claims that because it is free from government interference and draws on scientific metrics, their standards transcend localized, political–economic contexts. In this paper, we illustrate how the local context shapes the prospects for Bonsucro sustainably certified biofuel production in relation to land and water grabs. To accomplish this, our case focuses on Colombia, which has used a range of national policy mandates to establish itself as one of the larger producers of agrofuels in Latin America. We draw on interviews with stakeholders in the sugar and ethanol industries, paired with an examination of Bonsucro principles on land rights and water use, to illustrate how the sugar industry is framing their participation in Bonsucro, and the effects of the increasing intensification of sugarcane for ethanol production on land and water access for communities. We find that within the context of Colombia, efforts such as Bonsucro provide a veil of legitimacy and authority to a system that is premised on deeply entrenched historical patterns of inequitable land ownership patterns and access to natural resources. 相似文献
42.
A circadian rhythm orchestrated by histone deacetylase 3 controls hepatic lipid metabolism 总被引:4,自引:0,他引:4
Feng D Liu T Sun Z Bugge A Mullican SE Alenghat T Liu XS Lazar MA 《Science (New York, N.Y.)》2011,331(6022):1315-1319
Disruption of the circadian clock exacerbates metabolic diseases, including obesity and diabetes. We show that histone deacetylase 3 (HDAC3) recruitment to the genome displays a circadian rhythm in mouse liver. Histone acetylation is inversely related to HDAC3 binding, and this rhythm is lost when HDAC3 is absent. Although amounts of HDAC3 are constant, its genomic recruitment in liver corresponds to the expression pattern of the circadian nuclear receptor Rev-erbα. Rev-erbα colocalizes with HDAC3 near genes regulating lipid metabolism, and deletion of HDAC3 or Rev-erbα in mouse liver causes hepatic steatosis. Thus, genomic recruitment of HDAC3 by Rev-erbα directs a circadian rhythm of histone acetylation and gene expression required for normal hepatic lipid homeostasis. 相似文献
43.
The mechanisms that control localization of marginal zone (MZ) B cells are poorly understood. Here we show that MZ B cells express elevated levels of the integrins LFA-1 (alphaLbeta2) and alpha4beta1 and that they bind to the ligands ICAM-1 and VCAM-1. These ligands are expressed within the MZ in a lymphotoxin-dependent manner. Combined inhibition of LFA-1 and alpha4beta1 causes a rapid and selective release of B cells from the MZ. Furthermore, lipopolysaccharide-triggered MZ B cell relocalization involves down-regulation of integrin-mediated adhesion. These studies identify key requirements for MZ B cell localization and establish a role for integrins in peripheral lymphoid tissue compartmentalization. 相似文献
44.
Evaluation of signal detection algorithms within the Elanco Animal Health Pharmacovigilance database
Mark J. Novotny Austin Rhodes Jacob Shields Andrea Wilson Camilo Giraldo Michael OGorman Theresa Real Alexandra Sarsadskikh Scott Wiseman 《Journal of veterinary pharmacology and therapeutics》2021,44(1):107-115
Statistical algorithms for detecting safety signals are beginning to be applied to Animal Health Pharmacovigilance (PV) databases. How these signal detection algorithms (SDAs) perform in an animal health PV database is the subject of this report. Statistical methods and SDAs were assessed against a set of known signals in order to identify which SDAs were most appropriate for signal detection using the Elanco Animal Health PV database. A reference set of adverse events that should signal was created for 31 products across four species. Nine SDAs based on five disproportionality statistical methods were evaluated against the reference set. The performance metrics were sensitivity, precision, specificity, accuracy, and F score. For bovine and porcine products, the Observed‐to‐Expected (O/E) SDA was the closest in terms of geometric distance to 100% sensitivity and 100% precision. For canine and feline products, the Information Component (IC) SDA was geometrically closest to 100% sensitivity and 100% precision. Principal Component Analysis confirmed that the O/E and IC SDAs were unique performers with respect to one another and other SDAs. The performance of the SDAs was dependent on the choice of the statistical method with differences seen between animal species. 相似文献
45.
46.
Gregory B. Daniel DVM MS Russell L. Tucker DVM Janice M. Bright DVM MS Theresa A. Buckman AHT 《Veterinary radiology & ultrasound》1993,34(4):276-285
Equilibrium radionuclide ventriculograms were performed in 6 normal dogs during resting and isoproterenol challenged states. A new method of analysis of the equilibrium radionuclide ventriculograms using a simple digital subtraction technique was compared to traditional methods of analysis and echocardiography. There was no significant difference between ejection fraction values from the three methods tested. The equilibrium radionuclide ventriculograms ejection fraction was significantly increased following isoproterenol administration using both the new and traditional methods of analysis but the pre versus post-isoproterenol increase ejection fraction derived from echocardiographic measurements of ejection fractions was not significantly different. The new digital subtraction method consistently produced reproducible, high quality ventricular volume curves for the left and right ventricle. Left and right ventricular maximum and average emptying and filing rates were determined from the slopes of the volume curve and the results were similar to those previously published for man and dog. The emptying and filling rates of both ventricles were significantly increased following isoproterenol administration. The time to peak emptying significantly decreased following isoproterenol. Time to peak filing decreased following isoproterenol but the difference was not significant. 相似文献
47.
Gunn-Moore DA McCann TM Reed N Simpson KE Tennant B 《Journal of Feline Medicine and Surgery》2007,9(3):214-218
Faecal samples from 111 cats with diarrhoea that were living in the UK were submitted for the assessment of Tritrichomonas foetus infection by polymerase chain reaction (PCR). Sixteen (14.4%) samples were found to be positive. In agreement with studies from the USA, infected cats were predominantly of a year of age or less and of a pedigree breed, with Siamese and Bengal cats specifically over-represented in this population. 相似文献
48.
Michaela Kolářová Theresa A. Reinhardt Piskáčková Luděk Tyšer Thien T. Hoová 《Weed Research》2023,63(1):57-67
Herbicide resistance is a widespread issue that impacts management of conventional farms, but also has ramifications for the weed community assembly; it is therefore important to see how these species factor into the weed community assembly of farms throughout the countryside. This research analysed species richness and community diversity in 98 field relevés from 48 organic and 50 conventional farms evenly distributed between two major production regions of the Czech Republic and then evaluated the incidence of species which have been reported resistant in the Czech Republic and its neighbouring countries. Farms were selected independently of any acknowledged resistant species. Out of 164 species found in this survey, only eight species have had herbicide-resistant biotypes reported in the Czech Republic, while a total of 19 species had herbicide-resistant biotypes reported in neighbouring countries. Species with recorded resistance to PSII inhibitors in the Czech Republic tended to be found together and were mostly associated with the beet production region, characterised by low altitude: Amaranthus retroflexus, Chenopodium album, Echinochloa crus-galli and Solanum nigrum. Species with reported resistance to ALS and ACCase-inhibiting herbicides were not clearly associated with a particular region or farming type. Of the species which have had reported herbicide resistance in the neighbouring countries, several were found in conventional fields within the growing season and we recommend immediate screening for herbicide resistance in these species and more diligent action in management according to anti-resistance strategies: Bromus sterilis resistant to ACCase-inhibiting herbicides, A. retroflexus resistant to ALS-inhibiting herbicides or Avena fatua resistant to ACCase and ALS-inhibiting herbicides. This work is unique in that it is evaluating weed species diversity in organic and conventional farms and using the context to frame the prevalence of high-risk herbicide-resistant species; thereby putting the potential incidence of herbicide resistance into perspective at the landscape level. 相似文献
49.
Background
The Argentine ant, Linepithema humile, is a widespread invasive ant species that has successfully established in nearly all continents across the globe. Argentine ants are characterised by a social structure known as unicoloniality, where territorial boundaries between nests are absent and intraspecific aggression is rare. This is particularly pronounced in introduced populations and results in the formation of large and spatially expansive supercolonies. Although it is amongst the most well studied of invasive ants, very little work has been done on this ant in South Africa. In this first study, we investigate the population structure of Argentine ants in South Africa. We use behavioural (aggression tests) and chemical (CHC) approaches to investigate the population structure of Argentine ants within the Western Cape, identify the number of supercolonies and infer number of introductions.Results
Both the aggression assays and chemical data revealed that the Western Cape Argentine ant population can be divided into two behaviourally and chemically distinct supercolonies. Intraspecific aggression was evident between the two supercolonies of Argentine ants with ants able to discriminate among conspecific non-nestmates. This discrimination is linked to the divergence in cuticular hydrocarbon profiles of ants originating from the two supercolonies.Conclusions
The presence of these two distinct supercolonies is suggestive of at least two independent introductions of this ant within the Western Cape. Moreover, the pattern of colonisation observed in this study, with the two colonies interspersed, is in agreement with global patterns of Argentine ant invasions. Our findings are of interest because recent studies show that Argentine ants from South Africa are different from those identified in other introduced ranges and therefore provide an opportunity to further understand factors that determine the distributional and spread patterns of Argentine ant supercolonies. 相似文献50.
Rho JK Lee T Jung SI Kim TS Park YH Kim YM 《Journal of agricultural and food chemistry》2004,52(11):3269-3274
Qualitative and quantitative polymerase chain reaction (PCR) methods have been developed for the detection of genetically modified (GM) potatoes. The combination of specific primers for amplification of the promoter region of Cry3A gene, potato leafroll virus replicase gene, and potato virus Y coat protein gene allows to identify each line of NewLeaf, NewLeaf Y, and NewLeaf Plus GM potatoes. Multiplex PCR method was also established for the simple and rapid detection of the three lines of GM potato in a mixture sample. For further quantitative detection, the realtime PCR method has been developed. This method features the use of a standard plasmid as a reference molecule. Standard plasmid contains both a specific region of the transgene Cry3A and an endogenous UDP-glucose pyrophosphorylase gene of the potato. The test samples containing 0.5, 1, 3, and 5% GM potatoes were quantified by this method. At the 3.0% level of each line of GM potato, the relative standard deviations ranged from 6.0 to 19.6%. This result shows that the above PCR methods are applicable to detect GM potatoes quantitatively as well as qualitatively. 相似文献