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231.
Planning practice requires ongoing interaction between regulatory “facts” and deliberative “norms”. Played out in local and strategic developments, “norms” are the agreed values and positions developed by advancing deliberative engagement of residents; while “facts” are the more rigid statutory procedures through which planning decisions are typically made. However, conflict arises between residents' groups and local government decision-makers when deliberative norms, now a key tenet of strategic planning processes, struggle to gain traction in the factual spaces provided by statutory planning regulations. A contentious planning process in St Kilda, Melbourne, Australia (concerning the redevelopment of a car park into a commercial and public space) highlights the challenges to deliberative engagement in highly-regulatory planning systems. Drawing on this contested case, this paper examines how the broader formal and relatively fixed framework of regulatory-based decision-making fails to support participatory principles, undermining both the desired communicative ethos and enduring collaborative outcomes and norm development. Specifically, the paper problematises tensions between residents' growing expectations for greater transparency and participation in planning, arising from a growing regard for deliberation in strategic planning, and the hegemonic nature of statutory planning that preserves planning control within the formal domain of government and the private sector. 相似文献
232.
233.
Why Hydroxamates May Not Be the Best Histone Deacetylase Inhibitors—What Some May Have Forgotten or Would Rather Forget?
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Hydroxamate‐based histone deacetylase inhibitors (HDACIs) have been approved as therapeutic agents by the US Food and Drug Administration for use in oncology applications. While the potential utility of such HDACIs in other areas of medicinal chemistry is tremendous, there are significant concerns that “pan‐HDAC inhibitors” may be too broadly acting and/or toxic for clinical use beyond oncology. In addition to the isozyme selectivity challenge, the potential mutagenicity of hydroxamate‐containing HDAC inhibitors represents a major hindrance in their application to other therapeutic areas. Herein we report on the mutagenicity of known hydroxamates, discuss the mechanisms responsible for their genotoxicity, and review some of the current alternatives to hydroxamates. We conclude that the hydroxamate group, while providing high‐potency HDACIs, is not necessarily the best zinc‐binding group for HDACI drug discovery. 相似文献
234.
Concerns about the potential health effects of exposure to nanomaterials have led to a growing number of in vivo inhalation toxicity studies using nanoparticle aerosols. Estimates of aerosol deposition within the respiratory tract are important for these studies to enable: (a) the interpretation of the results, in particular, the evaluation of dose–response relationships; (b) comparison with the results of other related studies; and (c) the extrapolation of results from animal models to human. Unfortunately, only a limited number of studies have been undertaken to investigate respiratory tract deposition efficiencies for nano-sized aerosol particles. This is of particular importance as deposition efficiencies are predicted to vary significantly over the nano-size range for some elements of the respiratory tract. In this study, female Wistar-Kyoto rats were exposed in a new design nose-only inhalation exposure system to spark generated radioactive iridium-192 nanoparticle aerosols of four particle sizes chosen to cover the majority of the nano-size range (nominal sizes: 10, 15, 35, and 75 nm). The content of iridium-192 in the lung, head, gastrointestinal tract, and various other organs and tissues was measured. Aerosol deposition efficiencies in the whole respiratory tract and components (head airways, lung, alveolar region, and tracheobronchial region) were estimated and compared with the predictions of the Multiple Path Particle Dosimetry (MPPD) model (v2.11). The experimentally derived deposition efficiencies were broadly consistent with, but typically higher than, model predictions and the results of comparable studies in the literature.
Copyright © 2016 American Association for Aerosol Research 相似文献
235.
Abstract Lakes develop when pits from open cut mines are left to fill with groundwater. In recent years, mining companies, mining communities,
and regulatory agencies have begun to consider potential beneficial end uses for mine lakes. Beneficial end uses are unlikely
to be without environmental impacts, however, and a proper consideration of the total benefit to the community should consider
them. This paper briefly reviews potential beneficial end uses and possible environmental impacts that might arise with them
for mine lakes in the Collie Basin, a coal mining region in Western Australia. We identified eight distinct, but not necessarily
incompatible, end uses from a search of the literature on mine lakes throughout the world: recreation and tourism, wildlife
conservation, aquaculture, irrigation, livestock water, potable water, industrial water, and chemical extraction. Recreation,
conservation, and possibly aquaculture use the mine lake directly, whereas the other end uses utilise extracted water. All
end uses have the potential to have environmental effects, with the most common being an actual or perceived impact on human
health and safety. A semi-quantitative risk assessment, using published literature sources, identified wildlife conservation
as the end use with the least environmental risk, and irrigation as the end use with the greatest environmental risk. Such
risks need to be balanced against economic and social benefits. There is an urgent need for a regulatory framework to address
mine lake options. 相似文献
236.
This article presents results on the potential of using crystalline flame retardants for thermoset reinforcement. The approach involves introducing reinforcement in thermosetting polymers through low molecular weight crystallizable additives. Thermally induced phase separation (TIPS) and crystallization of desoxyanisoin in diglycidylether of bisphenol‐A (DGEBA) epoxy monomer were investigated. Small angle light scattering and polarized optical microscopy were utilized to monitor phase separation and the crystallization of desoxyanisoin in DGEBA at different concentrations. Reaction induced phase separation (RIPS) with polyetheramine was carried out under isothermal and temperature gradient curing conditions. Altering the cure schedule resulted in a rich range of morphologies due to the competition between TIPS and RIPS. During isothermal cure, straight fiber‐like anisotropic crystals on a centimeter length scale developed. In contrast, thermal gradients frustrated the crystal growth and resulted in complex and rich morphologies. Desoxyanisoin provided marginal epoxy thermoset reinforcement at 10 vol %. However, the additive did not increase the thermoset flammability retardancy. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39853. 相似文献
237.
Variable temperature 13C nuclear magnetic resonance (NMR) spinlattice (T1) relaxation studies were carried out using pure ethylbenzene, tetrahydrofuran, and methanol samples. Single correlation times, determined from an isotropic rotational diffusion model, were correlated successfully using the free-volume equation. The solvent free-volume parameters estimated in this study were comparable with those determined from viscosity measurements. The solvent free-volume parameters estimated in this study were then used to correlate and predict diffusion behavior of polymer/solvent systems. The results were comparable with those using the parameters from viscometry when the Vrentas–Duda free-volume diffusion model was used. 相似文献
238.
In this study, we compare the effect of twin-screw extrusion processing on the attrition of wood fibers (WFs) with glass fiber. The effects of process variables and screw design on fiber length were investigated by performing a range of dead-stop experiments where the extruder was stopped, opened-up, and compound removed from the screw elements. Fibers, chemically extracted from the polypropylene matrix, were analyzed for length and width using a commercial fiber analyzer. It was found that WF length attrition and composite properties were less affected by screw design and twin-screw processing conditions (feed rate and screw speed) than glass fiber. Length weighted fiber length and X50 length (a measure used in particle size analysis) were equally correlated with process conditions and composite performance for both fiber types. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48551. 相似文献
239.
The paper examines the ‘Distributed Summation’ problem, and its solution in Linda. A number of problems with the current set of primitives are examined, and a new primitive, collect, is proposed. 相似文献
240.
Software engineers have tacitly assumed that there exists a link between coverage and reliability. An argument is presented which leads to an inverse logarithmic relationship which depends upon the structure of the software and on a parameter called the strength of the coverage metric. The relationship is developed by considering reliability as a function of an idealized coverage metric and then interpreting the result for a range of actual coverage metrics. 相似文献