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211.
Disabled mobility and the production of impairment: The case of Australia's migration policy framework 下载免费PDF全文
In Australia, the transfer of asylum seekers to Nauru for ‘processing’ and the harm experienced by refugees in this context has been analysed from various perspectives, including criticisms that this is a form of torture. However, the harm experienced by refugees seeking asylum has not been considered through a southern disability theory (SDT) lens. Whilst SDT has been employed to examine various contexts, the framework has not explicitly been used to discuss the production of impairment in Nauru. Our application of this framework in this context highlights the Global North and Global South inequalities operating on the bodies of those refugees seeking asylum who are initially obstructed from entry into Australia. SDT also highlights some Global North framings that do not include the production of impairment in theorising disabling conditions. This obscures the power relations underpinning the policies generating harm to those in Nauru; however, SDT makes these power relations central, thus providing a better framework for appreciating what is occurring in Nauru and the ongoing refugee transition undertaken to ‘claim’ asylum in Australia. 相似文献
212.
When warmer means weaker: high temperatures reduce behavioural and immune defences of the larvae of a major grapevine pest 总被引:1,自引:0,他引:1
Corentin Iltis Guillaume Martel Denis Thiéry Jérôme Moreau Philippe Louâpre 《Journal of pest science》2018,91(4):1315-1326
Phytophagous insects evolving in agroecosystems express numerous defences when faced with myriads of natural enemies. Such defensive traits might impair the effectiveness of biological control relying on these natural enemies, mostly parasitoids. In the case of parasitoid threat, these defences consist of the avoidance of the parasitoid (reduced exposure to antagonists through shortening of developmental time), hindrance of oviposition (evasive behaviours and morphological protection) or destruction of the parasitoid eggs (encapsulation and melanisation by means of the immune system). Previous works focused on one defensive trait only when investigating the effects of temperature on host resistance. By doing so, they assumed that all defensive traits would respond uniformly to a change occurring in thermal environment, which remains an undocumented fact. To test this assumption in the context of global warming, we adopted a global overview of host resistance by examining the effects of rising temperatures on multiple defensive traits used by the grape pest, Lobesia botrana, against its larval parasitoids. Although warmer conditions led to reduced exposure to parasitoids by accelerating larval development, warmer conditions also elicited extensive weakening of behavioural and immune defences. These results confirm that temperatures might differently modulate the levels of expression of several defensive traits. An increase in growth rate and pupal mass also occurred, especially for females, which may contribute to greater pest fecundity in the future. However, the decline of L. botrana resistance might enhance the efficiency of the biological control naturally exerted by parasitoids in vineyards, thereby limiting the damage to crops. 相似文献
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Chris Ademola Bode-Aluko Omoniyi Pereao Guillaume Ndayambaje Leslie Petrik 《Water, air, and soil pollution》2017,228(1):35
Removal of toxic metals from aqueous solutions is of high priority in environmental chemistry. Most of the available techniques for this task are considered expensive; however, the adsorption process has been considered the easiest and the cheapest way of removing toxic metals from aqueous solution. The performance of adsorption setup largely depends on the characteristic of adsorbents. One of these characteristic is availability of large surface area. The more the available sites for chelation, the more the amount of metals removed. Therefore, the production of materials of nanoscale is expedient for adsorption purposes. Electrospinning process is one of the technologies that have been employed to produce polyacrylonitrile nanofibres (PAN-nfs). Moreover, PAN-nfs surfaces have also been chemically modified so as to introduce chelating groups such as amine, carboxyl, imines, etc. Here we review PAN-nfs as metal ion adsorbent. With characteristics such as high surface area as well as good mechanical strength, modified PAN-nfs are considered good adsorbents and have been used to remove toxic metals such as cadmium, lead, chromium, mercury, uranium, silver and copper in different ion states from their aqueous solutions. The ease of immobilization of metal-specific ligands on PAN-nfs has been of great interest in selective extraction of metal ions from their aqueous solutions. Also, toxic metals adsorbed on modified PAN-nfs can be recovered through desorption process using acids or bases of various concentrations. 相似文献
215.
ABSTRACT Verticillium dahliae is responsible for Verticillium wilt on a wide range of hosts, including strawberry, on which low soil inoculum densities can cause significant crop loss. Determination of inoculum density is currently done by soil plating but this can take 6 to 8 weeks to complete and delay the grower's ability to make planting decisions. To provide a faster means for estimating pathogen populations in the soil, a multiplexed TaqMan real-time polymerase chain reaction (PCR) assay based on the ribosomal DNA (rDNA) intergenic spacer (IGS) was developed for V. dahliae. The assay was specific for V. dahliae and included an internal control for evaluation of inhibition due to the presence of PCR inhibitors in DNA extracted from soil samples. An excellent correlation was observed in regression analysis (R(2) = 0.96) between real-time PCR results and inoculum densities determined by soil plating in a range of field soils with pathogen densities as low as 1 to 2 microsclerotia/g of soil. Variation in copy number of the rDNA was also evaluated among isolates by SYBR Green real-time PCR amplification of the V. dahliae-specific amplicon compared with amplification of several single-copy genes and was estimated to range from ≈24 to 73 copies per haploid genome, which translated into possible differences in results among isolates of ≈1.8 cycle thresholds. Analysis of the variation in results of V. dahliae quantification among extractions of the same soil sample indicated that assaying four replicate DNA extractions for each field sample would provide accurate results. A TaqMan assay also was developed to help identify colonies of V. tricorpus on soil plates. 相似文献
216.
Dogan B Rishniw M Bruant G Harel J Schukken YH Simpson KW 《Veterinary microbiology》2012,159(1-2):163-170
Escherichia coli infection is one of the most common causes of bovine mastitis in well managed dairies. Although E. coli infections are usually transient, E. coli can also cause persistent intramammary infections. We sought to determine whether E. coli isolates recovered from either transient or persistent intramammary infections differed both genetically and in their ability to invade mammary epithelial cells. E. coli isolates from transient (EC(trans), n=16) and persistent (EC(pers), n=12) mastitis cases were compared for differences in overall genotype, virulence genes, serotype, phylogroup (A, B1, B2, D), and invasion of bovine mammary epithelial cells, MAC-T by microarray analysis, suppressive subtractive hybridization, PCR and gentamicin protection assays. EC(trans) and EC(pers) were diverse in overall genotype and serotype, and were predominantly of phylogroups A and B1. Both EC(trans) and EC(pers) contained genes encoding type II, IV and VI secretion systems, long polar fimbriae (lpfA) and iron acquisition, and lacked genes associated with virulence in diarrheagenic E. coli. EC(trans) had fewer virulence genes than EC(pers) (p<0.05), but no individual virulence genes were unique to either group. In phylogroup A, EC(pers) were more invasive than EC(trans) (p<0.05), but no difference was observed between them in phylogroup B1. Enhanced epithelial cell invasion was associated with lpfA (p<0.05). Our findings indicate that a genetically diverse group of E. coli is associated with transient and persistent mastitis. We did not identify a set of bacterial genes to account for phenotypic differences. However, we found that mastitis phenotype, phylogroup and presence of lpfA were associated with the ability to invade cultured bovine mammary epithelial cells. 相似文献
217.
Fraipont A Van Erck E Ramery E Fortier G Lekeux P Art T 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(3):311-314
A field test and a standardized treadmill test were used to assess fitness in endurance horses. These tests discriminated horses of different race levels: horses participating in races of 120 km and more showed higher values of VLA4 (velocity at which blood lactate reached 4 mmol/L) and V200 (velocity at which heart rates reached 200 beats per min) than horses of lower race levels. 相似文献
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Philip Nti Nkrumah Guillaume Echevarria Peter D. Erskine Rufus L. Chaney Sukaibin Sumail Antony van der Ent 《植物养料与土壤学杂志》2019,182(5):715-728
Agromining is an emerging technology that utilizes selected ‘metal crops' (= hyperaccumulator plants) to extract valuable target metals from unconventional resources for profit from mineralised soils. Growth characteristics, shoot metal concentrations, and agrominable locations are important considerations in economic agromining. Globally, the greatest potential for nickel (Ni) agromining exists in the tropics. However, the agronomic systems of tropical ‘metal crops' have not been previously tested. Furthermore, it is currently unknown whether nutrient dosing of prospective tropical agromining Ni ‘metal crops’ could possibly cause a shoot Ni‐dilution effect which may ultimately limit economically viable Ni yields. We undertook a pioneering study on Ni uptake and growth responses to nutrient dosing in two promising tropical ‘metal crops' (Phyllanthus rufuschaneyi and Rinorea cf. bengalensis). The experiment consisted of a large randomised block growth trial in large pots over 12 months in Sabah (Malaysia). At 3‐month intervals, the plants were exposed to soluble treatments that altered available concentrations of nitrogen (N), phosphorus (P), and potassium (K). We found strong positive growth responses to N and P additions in P. rufuschaneyi, whereas K additions had negative growth effects. In R. cf. bengalensis, all treatments had positive growth effects. The increases in biomass in response to nutrient dosing did not significantly reduce shoot Ni concentrations in both species, with the exception of N addition in P. rufuschaneyi. This study reveals that Ni uptake and growth responses to nutrient dosing are species‐dependent, primarily influenced by the ecophysiology of the species. Inorganic fertilization could possibly be an important component of the management of local ‘metal crops' to be used in viable commercial agromining in the tropics, but this needs to be tested in the field with different formulations of N, P, and K. 相似文献
220.
Temporal variability of connectivity in agricultural landscapes: do farming activities help? 总被引:5,自引:0,他引:5
Baudry Jacques Burel Françoise Aviron Stéphanie Martin Manuel Ouin Annie Pain Guillaume Thenail Claudine 《Landscape Ecology》2003,18(3):303-314
Landscape Ecology - In landscapes where natural habitats have been severely fragmented by intensive farming, survival of many species depends on connectivity among habitat patches. Spatio-temporal... 相似文献