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31.
With 84 per cent of the Singapore resident population housed in public housing, the ultimate dream for many is to move into private housing, which is generally considered to offer better quality and more exclusive living. This article is concerned with the enabling factors of affordability in housing mobility. It examines the Singapore public housing homeowners' affordability of private housing, suggesting a measure of that affordability. The survey findings indicate that only a small percentage of public homeowners can afford to move to median-priced private apartments. The number is even smaller for the relatively more expensive landed housing with own garden. On a theoretical level, the study demonstrates that the use of multiple methods to measure housing affordability is beneficial as more affordability determinants are included in the measurement. 相似文献
32.
AL Okorokov KI Panov WA Offen VG Mukhortov AA Antson Karpeisky MYa AJ Wilkinson GG Dodson 《Canadian Metallurgical Quarterly》1997,10(3):273-278
We have developed a model of ischaemia-reperfusion injury in C57BL/6 mice involving ischaemia for 0.5 to 2.5 h with an elastic tourniquet on one hind limb and reperfusion for 24 h, analogous to a well-established model of ischaemia-reperfusion injury in the rat. Viability was assessed in tissue homogenates of the gastrocnemius muscles from the affected and contralateral control limb by a triphenyl tetrazolium chloride dye reaction, measuring the activity of the oxidative mitochondrial enzymes. After 1.5 h ischaemia and 24 h reperfusion, viability in the ischaemic-reperfused limb was 13%, with the control muscle regarded as 100% viable. Significant improvements in viability to 86% (P < 0.05) and 56% (P < 0.05) were achieved, with administration 30 min prior to tourniquet release, of the nitric oxide (NO) synthase inhibitor nitro-L-arginine methyl ester (L-NAME, 30 mg/kg) and the anti-inflammatory glucocorticoid dexamethasone (2.5 mg/kg) respectively, with similar findings in the rat tourniquet model. 相似文献
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The facial expressions of adults with Down's syndrome (DS; n?=?15) as they watched happy, sad, and neutral videotapes were compared with those of a healthy age-matched control group (n?=?20). Facial movements were analyzed with the Facial Action Coding System (P. E. Ekman & W. V. Friesen, 1978). While watching happy stimuli, the 10 DS adults who were able to appropriately rate their reactions smiled with a cheek raise as frequently as control adults, suggesting that the expression of positive affect in these individuals is normal. Contrary to predictions, however, the DS group exhibited fewer smiles without cheek raises than did control adults and were more likely not to smile. Neither group showed prototypic sad facial expressions in response to sad stimuli. Independent of emotion, DS participants made more facial movements, including more tongue shows, than did control participants. Differences in facial expression in DS adults may confuse others' interpretations of their emotional responses and may be important for understanding the development of abnormal emotional processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Memory judgments can be based on information that is more or less specific with respect to the source of an item. The authors introduce a procedure and multinomial model for measuring specific- and partial-source information. In 2 experiments, participants heard words spoken by 4 different voices: 2 male voices and 2 female voices. During the test, participants were required to remember who spoke the test items (e.g., Male 1, Male 2, Female 1, Female 2, or new word). Participants often remembered information about the gender of the source (i.e., partial-source information) when they did not remember information that identified the source itself (i.e., specific-source information). Dividing attention during retrieval impaired participants' memory for specific-source information (i.e., voice information) but did not affect memory for partial-source information (i.e., gender information). 相似文献
36.
Belinda A. Chiera Langford B. White 《International Journal of Adaptive Control and Signal Processing》2008,22(6):551-568
We investigate the application of a model‐free linear quadratic Gaussian (LQG) subspace‐based predictive controller to Internet congestion control. Specifically, we consider a classically designed LQG linear congestion controller with a non‐standard performance index and determine whether a model‐free controller is a viable alternative in this instance. We employ the model‐free subspace predictive controller methodology which we customize for end‐to‐end transmission control protocol (TCP) congestion control. A series of network simulations support the use of the more easily implementable model‐free controller over its classical analogue. We further demonstrate that the model‐free controller provides increased stability under transient network conditions when compared with the first feedback congestion controller, TCP Vegas. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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The pre-smolt stage of the scale of adult Norwegian Atlantic salmon from four populations, encompassing both farmed and wild hatchery stocks, has been analyzed by laser ablation inductively coupled plasma mass spectrometry (LA-HR-ICP-MS). The purpose of this study was to test for differences in elemental composition between stocks of Atlantic salmon that have lived in separate fresh water locations until the smoltification and natural run out or transportation to the sea-cages. The populations studied were from fish farms located at Bremanger and Sorfold, a cultivated stock from Mossa, and one wild local stock from the river Gaula. The following elements were included in the analytical protocol: Li, Mg, Ca, Cr, Mn, Fe, Zn, Sr, Ba, Pb, and U. Calcium was used as a natural internal standard. Classification of the analytical data is studied by multivariate statistical techniques such as principal component analysis (PCA). We have been able to delineate the population of Atlantic salmon (Salmo salar L.) from Gaula and Mossa from the Bremanger and the Sorfold stock based on the ten elements analyzed. The Bremanger and Sorfold stocks were partially delineated. The differences in elemental composition in the scales, which makes the delineating of the four stocks possible, probably reflects geological differences in the bedrock at the four fresh water locations experienced by the salmon during the pre-smolt stage. 相似文献
39.
Mammalian olfactory neurons possess a well-developed system of endocytic vesicles, endosomes, and lysosomes in their dendrites and perikarya. Vomeronasal neurons are similar and also contain much perikaryal agranular endoplasmic reticulum (AER). Olfactory supporting cells contain endocytic vesicles and endosomes associated closely with abundant fenestrated AER, and vesicles and numerous large dense vacuoles are present basally. Vomeronasal supporting cells have little AER, and few dense vacuoles occur in their bases. In olfactory neurons, ultrastructural tracers (0.08% horseradish peroxidase, thorium dioxide, ferritin) are endocytosed by olfactory receptor endings and transported to the cell body, where their movement is halted in lysosomes. Higher concentrations (1%) of horseradish peroxidase penetrate olfactory receptor plasma membranes and intercellular junctions. In olfactory supporting cells, endocytosed tracers pass through endosomes to accumulate in dense basal vacuoles. These observations indicate that olfactory sensory membranes are rapidly cycled and that endocytosed materials are trapped within the epithelium. It is proposed that in the olfactory epithelium, endocytosis presents redundant odorants to the enzymes of the supporting cell AER to prevent their accumulation, whereas in the vomeronasal epithelium the receptor cells carry out this activity. 相似文献