2,215 research outputs found
Theatrical Deception: Shakespearean Allusion in John Fowles’ \u3cem\u3eThe Magus: A Revised Version \u3c/em\u3e
Readers of either or both versions of John Fowles\u27 The Magus frequently express discomfort in assessing the work. One finds the 1966 original edition too difficult, labeling it pretentious and self-indulgent (Allen 65). Moderating this position, another critic praises its intellectual power and thematic resolution, but then calls the latter a partial failure (Rubenstein 339). Others acknowledge the author\u27s ambitiousness (Scholes 12), one describing the novel as a brilliant puzzle (Rackham 95). The 1978 revision, The Magus: A Revised Version, meets the same uneasy and uncertain reaction as did the earlier edition. According to one reader, The essential opacity of the original novel has not been removed in the revised version, yet the latter is unquestionably superior to the original (Wade 716). Another reader cannot see these improvements (Glasersfeld 444). And a third actually finds the new edition not more polished or elegant than the earlier work … simply duller (Lever 86)
Assessment of changes in potential nutrient limitation in an impounded river after application of lanthanum-modified bentonite
With the advent of phosphorus (P)-adsorbent materials and techniques to address eutrophication in aquatic systems, there is a need to develop interpretive techniques to rapidly assess changes in potential nutrient limitation. In a trial application of the P-adsorbent, lanthanum-modified bentonite (LMB) to an impounded section of the Canning River, Western Australia, a combination of potential P, nitrogen (N) and silicon (Si) nutrient limitation diagrams based on dissolved molar nutrient ratios and actual dissolved nutrient concentrations have been used to interpret trial outcomes. Application of LMB resulted in rapid and effective removal of filterable reactive P (FRP) from the water column and also effectively intercepted FRP released from bottom sediments until the advent of a major unseasonal flood event. A shift from potential N-limitation to potential P-limitation also occurred in surface waters. In the absence of other factors, the reduction in FRP was likely to be sufficient to induce actual nutrient limitation of phytoplankton growth. The outcomes of this experiment underpins the concept that, where possible in the short-term, in managing eutrophication the focus should not be on the limiting nutrient under eutrophic conditions (here N), but the one that can be made limiting most rapidly and cost-effectively (P)
Balancing Pastoral and Plantation Forestry Options in New Zealand and the Role of Agroforestry
Pastoral agriculture and forestry enterprises are key features of New Zealand’s landscape and are very important economically. They are competing landuses, particularly on moderate to steep hill country. Agroforestry involving spaced trees of Pinus radiata on pasture was developed in the 1970s to provide dual incomes from livestock enterprises and the later tree crop. In contrast, wide-spaced trees of predominantly Populus and Salix spp. are planted mainly for erosion control. Characteristics of pastoralism and plantation forestry are reviewed, including trends in conversions between these landuses. Roles, challenges and opportunities with wide-spaced trees are presented, together with current and future research initiatives. Pastoralism and forestry will continue to compete strongly for hill country sites and at present there is an increasing trend of converting previously forested areas to pasture, particularly in the central North Island. Agroforestry involving Pinus radiata has virtually ceased because of adverse effects on wood quality, pasture production and animal performance. There are millions of wide-spaced trees of Populus and Salix spp. on hill country and their planting is expected to continue unabated because they are the most practical and efficient means of enabling pastoralism on erodible slopes and they provide multiple ecosystem services. The species have significant advantages compared to other woody species but many older trees have grown very large because they have received negligible or no silviculture. This is an increasing problem, requiring development and implementation of appropriate management strategies. There is growing interest by landowners in the environmental outcomes of spaced-tree plantings
Engineered mineralogical interfaces as radionuclide repositories
Effective capture of fugitive actinides and daughter radionuclides constitutes a major remediation challenge at legacy or nuclear accident sites globally. The ability of double-layered, anionic clay minerals known as hydrotalcites (HTC) to contemporaneously sequester a range of contaminants from solution offers a unique remedy. However, HTC do not provide a robust repository for actinide isolation over the long term. In this study, we formed HTC by in-situ precipitation in a barren lixiviant from a uranium mine and thermally transformed the resulting radionuclide-laden, nanoscale HTC. Atomic-scale forensic examination of the amorphized/recrystallised product reveals segregation of U to nanometre-wide mineral interfaces and the local formation of interface-hosted mineral grains. This U-phase is enriched in rare earth elements, a geochemical analogue of actinides such as Np and Pu, and represents a previously unreported radionuclide interfacial segregation. U-rich phases associated with the mineral interfaces record a U concentration factor of ~ 50,000 relative to the original solute demonstrating high extraction and concentration efficiencies. In addition, the co-existing host mineral suite of periclase, spinel-, and olivine-group minerals that equate to a lower mantle, high P–T mineral assemblage have geochemical and geotechnical properties suitable for disposal in a nuclear waste repository. Our results record the efficient sequestering of radionuclides from contaminated water and this novel, broad-spectrum, nanoscale HTC capture and concentration process constitutes a rapid solute decontamination pathway and solids containment option in perpetuity
Interplay between CCN1 and Wnt5a in endothelial cells and pericytes determines the angiogenic outcome in a model of ischemic retinopathy
CYR61-CTGF-NOV (CCN)1 is a dynamically expressed extracellular matrix (ECM) protein with critical functions in cardiovascular development and tissue repair. Angiogenic endothelial cells (ECs) are a major cellular source of CCN1 which, once secreted, associates with the ECM and the cell surface and tightly controls the bidirectional flow of information between cells and the surrounding matrix. Endothelium-specific CCN1 deletion in mice using a cre/lox strategy induces EC hyperplasia and causes blood vessels to coalesce into large flat hyperplastic sinuses with no distinctive hierarchical organization. This is consistent with the role of CCN1 as a negative feedback regulator of vascular endothelial growth factor (VEGF) receptor activation. In the mouse model of oxygen-induced retinopathy (OIR), pericytes become the predominant CCN1 producing cells. Pericyte-specific deletion of CCN1 significantly decreases pathological retinal neovascularization following OIR. CCN1 induces the expression of the non-canonical Wnt5a in pericyte but not in EC cultures. In turn, exogenous Wnt5a inhibits CCN1 gene expression, induces EC proliferation and increases hypersprouting. Concordantly, treatment of mice with TNP470, a non-canonical Wnt5a inhibitor, reestablishes endothelial expression of CCN1 and significantly decreases pathological neovascular growth in OIR. Our data highlight the significance of CCN1-EC and CCN1-pericyte communication signals in driving physiological and pathological angiogenesis
Single and Compound Knock-outs of MicroRNA (miRNA)-155 and Its Angiogenic Gene Target CCN1 in Mice Alter Vascular and Neovascular Growth in the Retina via Resident Microglia
The response of the retina to ischemic insult typically leads to aberrant retinal neovascularization, a major cause of blindness. The epigenetic regulation of angiogenic gene expression by miRNAs provides new prospects for their therapeutic utility in retinal neovascularization. Here, we focus on miR-155, a microRNA functionally important in inflammation, which is of paramount importance in the pathogenesis of retinal neovascularization. Whereas constitutive miR-155-deficiency in mice results in mild vascular defects, forced expression of miR-155 causes endothelial hyperplasia and increases microglia count and activation. The mouse model of oxygen-induced retinopathy, which recapitulates ischemia-induced aberrant neovessel growth, is characterized by increased expression of miR-155 and localized areas of microglia activation. Interestingly, miR-155 deficiency in mice reduces microglial activation, curtails abnormal vessel growth, and allows for rapid normalization of the retinal vasculature following ischemic insult. miR-155 binds to the 3'-UTR and represses the expression of the CCN1 gene, which encodes an extracellular matrix-associated integrin-binding protein that both promotes physiological angiogenesis and harnesses growth factor-induced abnormal angiogenic responses. Single CCN1 deficiency or double CCN1 and miR-155 knock-out in mice causes retinal vascular malformations typical of faulty maturation, mimicking the vascular alterations of miR-155 gain of function. During development, the miR-155/CCN1 regulatory axis balances the proangiogenic and proinflammatory activities of microglia to allow for their function as guideposts for sprout fusion and anastomosis. Under ischemic conditions, dysregulated miR-155 and CCN1 expression increases the inflammatory load and microglial activation, prompting aberrant angiogenic responses. Thus, miR-155 functions in tandem with CCN1 to modulate inflammation-induced vascular homeostasis and repair
Successful Establishment of Oversown Chicory and Plantain on Uncultivatable Hill Country
All-year grazing of livestock on steep, non-arable hill country (\u3e 20o slope angle, \u3c 1,000 m elevation) is a significant feature of New Zealand agriculture. Hill country pastures are in various states of improvement depending on factors such as extent of subdivision, fertiliser inputs, plant species introduction, and grazing management. Numerous introduced grass, legume and herb species are available to match the many micro-sites in steep hill country (Kemp et al. 1999).
There has been increasing use of the perennial herbs chicory (Chicorium intybus L.) and plantain (Plantago lanceolata L.) in seed mixtures used on a range of topographies, mostly flat to undulating terrain. Advantages of these species include tolerance of drought and high summer temperatures, highly palatable foliage, enhanced mineral content, and high animal growth rates (Stewart 1996; Li and Kemp 2005). Farmers have sown these species on hill country but there is negligible information on their establishment in such landscapes. As part of a large, New Zealand-wide programme to increase pasture productivity on non-arable hill country through new germplasm introduction, chicory and plantain were included in a seed mixture broadcast-sown at a range of sites. This paper reports on the seedling establishment of these two species
Bacterial swarming reduces Proteus mirabilis and Vibrio parahaemolyticus cell stiffness and increases β-lactam susceptibility
Swarmer cells of the gram-negative pathogenic bacteria Proteus mirabilis and Vibrio parahaemolyticus become long (>10-100 microns) and multinucleate during their growth and motility on polymer surfaces. We demonstrate increasing cell length is accompanied by a large increase in flexibility. Using a microfluidic assay to measure single-cell mechanics, we identified large differences in swarmer cell stiffness of (bending rigidity of P. mirabilis, 9.6 x 10^(-22) N m^2; V. parahaemolyticus, 9.7 x 10^(-23) N m^2) compared to vegetative cells (1.4 x 10^(-20) N m^2 and 3.2 x 10^(-22) N m^2, respectively). The reduction in bending rigidity (~3-15 fold) was accompanied by a decrease in the average polysaccharide strand length of the peptidoglycan layer of the cell wall from 28-30 to 19-22 disaccharides. Atomic force microscopy revealed a reduction in P. mirabilis peptidoglycan thickness from 1.5 nm (vegetative) to 1.0 nm (swarmer) and electron cryotomography indicated changes in swarmer cell wall morphology. P. mirabilis and V. parahaemolyticus swarmer cells became increasingly sensitive to osmotic pressure and susceptible to cell wall-modifying antibiotics (compared to vegetative cells)--they were ~30% more likely to die after 3 h of treatment with minimum inhibitory concentrations of the beta-lactams cephalexin and penicillin G. Long, flexible swarmer cells enables these pathogenic bacteria to form multicellular structures and promotes community motility. The adaptive cost of swarming is offset by a fitness cost in which cells are more susceptible to physical and chemical changes in their environment, thereby suggesting the development of new chemotherapies for bacteria that leverage swarming for survival
The Classification of Obsessive–Compulsive and Related Disorders in the ICD-11
Background To present the rationale for the new Obsessive–Compulsive and Related Disorders (OCRD) grouping in the Mental and Behavioural Disorders chapter of the Eleventh Revision of the World Health Organization’s International Classification of Diseases and Related Health Problems (ICD-11), including the conceptualization and essential features of disorders in this grouping. Methods Review of the recommendations of the ICD-11 Working Group on the Classification for OCRD. These sought to maximize clinical utility, global applicability, and scientific validity. Results The rationale for the grouping is based on common clinical features of included disorders including repetitive unwanted thoughts and associated behaviours, and is supported by emerging evidence from imaging, neurochemical, and genetic studies. The proposed grouping includes obsessive–compulsive disorder, body dysmorphic disorder, hypochondriasis, olfactory reference disorder, and hoarding disorder. Body-focused repetitive behaviour disorders, including trichotillomania and excoriation disorder are also included. Tourette disorder, a neurological disorder in ICD-11, and personality disorder with anankastic features, a personality disorder in ICD-11, are recommended for cross-referencing. Limitations Alternative nosological conceptualizations have been described in the literature and have some merit and empirical basis. Further work is needed to determine whether the proposed ICD-11 OCRD grouping and diagnostic guidelines are mostly likely to achieve the goals of maximizing clinical utility and global applicability. Conclusion It is anticipated that creation of an OCRD grouping will contribute to accurate identification and appropriate treatment of affected patients as well as research efforts aimed at improving our understanding of the prevalence, assessment, and management of its constituent disorders
Astronaut Thermal Exposure: Re-Entry After Low Earth Orbit Rescue Mission
The STS-125 mission, launched May 11, 2009, is the final servicing mission to the Hubble Space Telescope. The repair mission's EVA tasks are described, including: installing a new wide field camera; installing the Cosmic Origins Spectrograph; repairing the Space Telescope Imaging Spectrograph; installing a new outer blanket layer; adding a Soft Capture and Rendezvous System for eventual controlled deorbit in about 2014; replacing the 'A' side Science Instrument Command and Data Handling module; repairing the Advanced Camera for surveys; and, replacing the rate sensor unit gyroscopes, fine guidance sensors and 3 batteries. Additionally, the Shuttle crew cabin thermal environment is described. A CFD model of per person CO2 demonstrates a discrepancy between crew breathing volume and general mid-deck levels of CO2. A follow-on CFD analysis of the mid-deck temperature distribution is provided. Procedural and engineering mitigation plans are presented to counteract thermal exposure upon reentry to the Earth atmosphere. Some of the procedures include: full cold soak the night prior to deorbit; modifying deck stowage to reduce interference with air flow; and early securing of avionics post-landing to reduce cabin thermal load prior to hatch opening. Engineering mitigation activities include modifying the location of the aft starboard ICUs, eliminating the X3 stack and eliminating ICU exhaust air directed onto astronauts; improved engineering data of ICU performance; and, verifying the adequacy of mid-deck temperature control using CFD models in addition to lumped parameter models. Post-mitigation CFD models of mid-deck temperature profiles and distribution are provided
- …