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Safety is recognised as an important goal of urban regeneration projects and implementing the principles of Crime Prevention Through Environmental Design (CPTED) has been proposed as one way of enhancing community safety. Yet there are few critiques of how effective CPTED is in achieving this. This paper reports on a pilot study that explores the link between CPTED principles and people’s feelings of safety and comfort in an urban precinct of Adelaide, South Australia. The research combines a micro-scale analysis of the built environment and a series of interviews with people who live and/or work in the area. The research highlights the importance of some of the CPTED principles including activity, maintenance, sight lines but also reveals the importance of familiarity and personal safety strategies. 相似文献
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Michael L. Benjamin Susan Arnold Marepalli Rao Kermit Davis Andrew Maier Jurate Virkutyte 《Indoor air》2021,31(1):128-140
Associations between cleaning chemical exposures and asthma have previously been identified in professional cleaners and healthcare workers. Domestic workers, including housecleaners and caregivers, may receive similar exposures but in residential environments with lower ventilation rates. Study objectives were to compare exposures to occupational exposure limits (OELs), to determine relative contributions from individual cleaning tasks to overall exposure, and to evaluate the effects of ventilation and posture on exposure. Airborne chemical concentrations of sprayed cleaning chemicals (acetic acid or ammonia) were measured during typical cleaning tasks in a simulated residential work environment. Whole-house cleaning exposures (18 cleaning tasks) were measured using integrated personal sampling methods. Individual task exposures were measured with a sampling line attached to subjects' breathing zones, with readings recorded by a ppbRAE monitor, equipped with a photoionization detector calibrated for ammonia and acetic acid measurements. Integrated sampling results indicated no exposures above OELs occurred, but 95th percentile air concentrations would require risk management decisions. Exposure reductions were observed with increased source distance, with lower exposures from mopping floors compared to kneeling. Exposure reductions were also observed for most but not all tasks when ventilation was used, with implications that alternative exposure reduction methods may be needed. 相似文献
996.
Poly(ethylene glycol)s of all molecular weights are highly soluble in water. Small-Angle Neutron Scattering (SANS) data has been collected on buffered ionic D2O solutions of PEGs of nominal molecular weights 2000, 4000, and 8000 Da at a low concentration of 0.5% (w/v). The radii of gyration Rg vary as approximately Mw0.5, which is consistent with both a Gaussian chain and a flat plate. Numerous types of experiments indicate flaws in the interpretation as a Gaussian chain. When the alternative interpretation is used, the structures in these dilute solutions are found to have a constant area stoichiometry of 1:1 water:-CH2CH2O- and are consistent with the data when monomeric molecules are plates of packed chains one chain thick. 相似文献
997.
In Peru modern perceptions of class, ethnicity, and social identity dictate whether the domesticated guinea pig (cuy) is considered a delicacy or an unpalatable indigenous food item. In the southern Peruvian city of Moquegua the breeding of cuyes, including the occurrence of many polydactyl individuals, the location of restaurants that serve cuy, meal costs, and behavior associated with cuy consumption attest to the animal's value beyond its dietary role. Partaking of a restaurant-prepared cuy reinforces social bonds and low sierra cultural identity. However, for some upper-class residents in Moquegua and for the majority of residents in the nearby industrial port city of Ilo, the cuy is considered an anomalous food item associated with indigenous culture and is not consumed. Food trends involving either the popularity or the rejection of a traditional Andean meat source reflect ongoing cultural change within sierra and coastal societies in Peru and have implications for other geographic areas. 相似文献
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Alexandra-Zoi Andreou Ellen Hornung Susan Kunze Sabine Rosahl Ivo Feussner 《Lipids》2009,44(3):207-215
Lipoxygenases (LOX; linoleate:oxygen oxidoreductase EC 1.13.11.12) consist of a class of enzymes that catalyze the regio-
and stereo specific dioxygenation of polyunsaturated fatty acids. Here we characterize two proteins that belong to the less
studied class of 9-LOXs, Solanum tuberosum StLOX1 and Arabidopsis thaliana AtLOX1. The proteins were recombinantly expressed in E. coli and the product specificity of the enzymes was tested against different fatty acid substrates. Both enzymes showed high specificity
against all tested C18 fatty acids and produced (9S)-hydroperoxides. However, incubation of the C20 fatty acid arachidonic acid with AtLOX1 gave a mixture of racemic hydroperoxides.
On the other hand, with StLOX1 we observed the formation of a mixture of products among which the (5S)-hydroperoxy eicosatetraenoic acid (5S-H(P)ETE) was the most abundant. Esterified fatty acids were no substrates. We used site directed mutagenesis to modify a conserved
valine residue in the active site of StLOX1 and examine the importance of space within the active site, which has been shown
to play a role in determining the positional specificity. The Val576Phe mutant still catalyzed the formation of (9S)-hydroperoxides with C18 fatty acids, while it exhibited altered specificity against arachidonic acid and produced mainly
(11S)-H(P)ETE. These data confirm the model that in case of linoleate 9-LOX binding of the substrate takes place with the carboxyl-group
first.
Sequence data: The nucleotide sequences reported in this paper are annotated in the GenBank/EMBL data bank under the accession
numbers Q06327 and S73865. 相似文献
999.
Susan Parham 《Journal of Urbanism》2018,11(4):503-504
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