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1.
RICHARD RONALD 《Housing Studies》2007,22(4):473-493
Distinguishable patterns of mass homeownership have emerged across industrialised societies in recent decades, and have become increasingly central in comparative analyses of housing systems. This paper examines the nature of differences and similarities within and between two particular groups of societies where owner occupation dominates housing demand and policy systems, one constituted of English-speaking, Anglo-Saxon societies, and another of East Asian societies. The paper considers the potential of forming loose models based on core divergences in terms of systems, regimes and socio-ideological relationships. The aim is to further illustrate interactions between housing systems and welfare regimes in international contexts. Comparisons of housing and welfare elements are broadly related between societies, rather than quantitatively isolated, as systems are substantially variegated across the East Asian region. However, a loose system-model provides considerable insight into convergence within the group in regards to how housing systems have served a minimal social-welfare regime type. 相似文献
2.
RICHARD C. HULA 《Journal of Urban Affairs》1985,7(3):39-56
This paper attempts to measure the effect of a court-ordered desegregation plan on three aspects of the housing market in Dallas County, Texas. The indicators include sale price, number of sales, and proportion of home sales financed by conventional mortgages. Monthly data from 1969 to 1979 are analyzed using Box-Jenkins time series models. After best fit models are determined, various intervention terms are introduced into the models to assess the impact of both a 1975 Circuit Court Order and a 1976 District Court Order. The analysis suggests neither order had a measurable effect on the housing market in Dallas. 相似文献
3.
Sucrose crystallization in thin films (50–55 μm) was studied, using a videomicroscopy technique, at conditions encountered during hard panning processes. No nucleation occurred in unseeded films, while a linear increase in seeded crystals occurred during drying. Crystal growth rate increased with temperature (25–30°C) and with air velocity (2.4–12.5 m/sec), but did not change with varying sucrose concentrations (70–76% w/w) and relative humidities (0–66% at 30°C). FD & C Yellow No. 5 food coloring in the dye form (0.05–0.5 g/100 mL) showed no effects while similar concentrations in the lake form inhibited crystal growth rate. 相似文献
4.
A study was conducted from 1978 to late 1984 of the survival of inner-city street trees planted by the Oakland, California urban forestry program. The tree survival rate of approximately 60 to 70 percent from the trees planted in neighborhood parkways through urban forestry sponsored block parties contrasted sharply with less than one percent survival of trees planted earlier by the Model Cities program without community participation or ceremonial plantings. Explanations for the high tree survival were tested using participant observation, interviews with residents, and a small panel. Tree survival was not found to be related to the explanations provided by urban forestry ideology; namely, that residents had been educated to hold both instrumental and expressive values toward trees. Rather, the explanation appeared to be the function of an unintended solution to the issue of parkway ownership. The tree planting process which included species selection meetings and tree planting ceremonies tended to define the parkway trees as a resident's property, thus decreasing the significance of the parkway-property barrier. The generality of the Oakland illustration is discussed. 相似文献
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7.
ANN M. GUENTERT RABI H. MOHTAR RICHARD H. LINTON MARK TAMPLIN JOHN B. LUCHANSKY 《Journal of food process engineering》2006,29(1):89-117
Listeria monocytogenes grows at refrigeration temperatures (5C or below) and tolerates various environmental stressors. The Food and Drug Administration specifies a zero tolerance for this pathogen in certain ready‐to‐eat processed foods. Modeling its dynamic behavior to fluctuation in temperature at various pH levels is critical to the safety of food. This study presents linear and nonlinear models to predict the behavior of L. monocytogenes in pH‐modified chicken salad at various cold storage and temperature abuse conditions. A linear model of the kinetics accounting for simple and interactive effects of storage time, temperature and pH was developed. Predictions of the linear model were inconsistent with laboratory observations. The limitations of the linear model were reflected in the poor correlation of model predictions to the observed values (r2 = 0.58). A proposed nonlinear model was therefore used to model the observed data. The four model parameters (N(0), Cc(0), kmax and Nres ) were optimized for each of the nine treatments. Correlation coefficient (r2) values ranged from 0.70 (pH 5.2, 7.2C) to 0.99 (pH 4.0, 21.1C), indicating an improved accuracy. Developing a functional and validated microbial predictive model for chicken salad requires further analyses and collection of data at additional pH and temperature values to determine a single set of parameter values that would represent the microbial behavior at the full range of pH and temperatures observed under storage conditions. Future experiments should address the adaptive nature of L. monocytogenes, as the response to environmental stressors affects the survival of the organism in food systems. 相似文献
8.
Stoichiometric NiAl2 O4 , CuAl2 O4 , and ZnAl2 O4 spinels were prepared and equilibrated at temperatures from 600° to 1400°C. The parameters u and x , denoting the oxygen position and fraction of divalent cations on tetrahedral sites, respectively, were determined from a detailed X-ray diffraction analysis. In NiAl2 O4 , x increased from 0.07 at 595° to 0.26 at 1391°C; in CuAl2 O4 , x decreased from 0.68 at 613° to 0.64 at 1195°C; and in ZnAl2 O4 , x decreased from 0.96 at 905° to 0.94 at 1197°C. The form of the temperature dependence of x could not be described using theoretically based equations advanced in the literature. A more general equation which allows for a non-distributional contribution to the configurational entropy was derived and observed to properly describe the temperature dependence; the results indicate that short-range order is of definite significance in these intermediate aluminate spinels. 相似文献
9.
RICHARD A. EPPLER 《Journal of the American Ceramic Society》1983,66(11):794-801
The system Zn2 TiO4 -Co2 TiO4 -Ni2 TiO4 yields a bright green pigment with the orthotitanate spinel structure. Brick-red, orange, and brown pigments are found in the system Zn2 TiO4 -Co2 TiO4 -Ni2 TiO4 . 相似文献
10.
INTROGRESSING PHEROMONE QTL BETWEEN SPECIES: TOWARDS AN EVOLUTIONARY UNDERSTANDING OF DIFFERENTIATION IN SEXUAL COMMUNICATION 总被引:2,自引:0,他引:2
Groot AT Ward C Wang J Pokrzywa A O'Brien J Bennett J Kelly J Santangelo RG Schal C Gould F 《Journal of chemical ecology》2004,30(12):2495-2514
As a first step toward understanding how noctuid moths evolve species-specific pheromone communication systems, we hybridized and backcrossed two closely related moth species, Heliothis virescens (Hv) and H. subflexa (Hs), which differ qualitatively and quantitatively in their multi-component sex pheromone blends. We used amplified fragment length polymorphism (AFLP) marker-based mapping of backcross families to determine which of the 30 autosomes in these moths contained quantitative trait loci (QTL) controlling the percentages of specific chemical components in the pheromone blends. In two previous backcrosses to Hs, we found a strong depressive effect of Hv-chromosome 22 on the percentage of three acetate components in the pheromone gland. These acetates are present in Hs and absent in Hv. Here, we describe how we introgressed Hv-chromosome 22 into the genomic background of Hs. Selection for Hv-chromosome 22 started from backcross 3 (BC3) females. All females that had Hv-chromosome 22 and a low percentage of acetates (< 3% of the total amount of pheromone components present) were backcrossed to Hs males. In BC5 to BC8, we determined whether Hv-chromosome 22 was present by a) running only the primer pairs that would yield the markers for that chromosome, and/or b) determining the relative percentages of acetates in the pheromone glands. Either or both genotype and phenotype were used as a criterion to continue to backcross these females to Hs males. In BC9, we confirmed the isolation of Hv-chromosome 22 in the Hs genomic background, and backcrossed the males to Hs females to eliminate the Hv-sex chromosome as well as mitochondrial DNA. The pheromone composition was determined in BC3, BC5, and BC11 females with and without Hv-chromosome 22. All backcross females with Hv-chromosome 22 contained significantly less acetates than females without this chromosome. In addition, BC3 females with Hv-chromosome 22 contained significantly more Z11-16:OH than BC3 females without Hv-chromosome 22. However, in BC5 and BC11 females, the correlation between Z11-16:OH and Hv-chromosome 22 was lost, suggesting that there are separate QTL for the acetates and for Z11-16:OH, and that the relative amount of the alcohol component is only affected in epistasis with other (minor) QTL. Now that we have succeeded in isolating the chromosome that has a major effect on acetate production, we can test in behavioral experiments whether the presence of acetates may have been a driving force for a shift in pheromone composition. Such tests are necessary to move towards an evolutionary understanding of the differentiation in sexual communication in Heliothis spp. moths. 相似文献