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31.
In Norway, as in many other countries, homeownership is encouraged politically, and a majority of the households become homeowners at some stage in their life cycle. Many households move house when circumstances change, and it is often at this point that they also make their tenure choice. This paper employs a bivariate probit framework to model the transition rate from renting into homeownership. Using a sample of initial renters, subsequent tenure choice is analysed jointly with the stay-move decision. A particularly important question in this context is whether low-income households face differential constraints on entering owner occupation that could be addressed by policy change. The empirical model includes financial characteristics, household characteristics and changes in household characteristics as explanatory variables. Changes in household composition are particularly important in explaining variations in both tenure choice and mobility. Hence, the common practice of estimating housing market behaviour using a panel of intact households potentially obfuscates important determinants of that behaviour. The paper proceeds by using the equivalent of a Chow test to show that a hypothesis of equal coefficients in samples of low- and high-income households is firmly rejected. Thus low-income households do behave differently. Short-term variations in income appear to have little effect on people's capacity to enter owner occupation. However, low-income households are more dependent on past savings for successful entry. This suggests a rather different policy approach if owner occupation is to be expanded. 相似文献
32.
Nyström B Becker-Van Slooten K Bérard A Grandjean D Druart JC Leboulanger C 《Water research》2002,36(8):2020-2028
Irgarol 1051 is a recent herbicidal compound, inhibitor of photosynthesis, used in antifouling paints. This toxic is persistent in aquatic environments, with low abiotic and biotic degradation, highly phytotoxic, and has already been detected in estuaries and coastal areas, with suspected negative impacts on non-target organisms (aquatic plants and algae). We measured the toxicity of Irgarol 1051 to macrophytes and phytoplankton from Lake Geneva (between Switzerland and France) by determining chlorophyll fluorescence yield, and phytoplankton primary production. Long-term toxicity for phytoplankton was estimated in a microcosm study, and growth inhibition tests were performed with isolated algal strains. The concentration of Irgarol 1051 was analysed in the water, and the most polluted site showed a higher level (up to 135 ng/L) than the lowest observed effect concentration for phytoplankton (8-80 ng/L), while the macrophytes appeared to be more tolerant to Irgarol 1051 in short-term tests. The microcosm study showed that phytoplankton structure might be even more sensitive to Irgarol 1051. 相似文献
33.
Skin Texture Modeling 总被引:1,自引:0,他引:1
Cula Oana G. Dana Kristin J. Murphy Frank P. Rao Babar K. 《International Journal of Computer Vision》2005,62(1-2):97-119
34.
Kiehl Kent A.; Bates Alan T.; Laurens Kristin R.; Hare Robert D.; Liddle Peter F. 《Canadian Metallurgical Quarterly》2006,115(3):443
Psychopathy is associated with abnormalities in attention and orienting. However, few studies have examined the neural systems underlying these processes. To address this issue, the authors recorded event-related potentials (ERPs) while 80 incarcerated men, classified as psychopathic or nonpsychopathic via the Hare Psychopathy Checklist-Revised (R. D. Hare, 1991, 2003), completed an auditory oddball task. Consistent with hypotheses, processing of targets elicited larger frontocentral negativities (N550) in psychopaths than in nonpsychopaths. Psychopaths also showed an enlarged N2 and reduced P3 during target detection. Similar ERP modulations have been reported in patients with amygdala and temporal lobe damage. The data are interpreted as supporting the hypothesis that psychopathy may be related to dysfunction of the paralimbic system--a system that includes parts of the temporal and frontal lobes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Erik Andreassen Kristin Grstad Ole Jan Myhre Marianne D. Braathen Einar L. Hinrichsen Anne Marie V. Syre Tor Bertel Lvgren 《应用聚合物科学杂志》1995,57(9):1075-1084
Polypropylene fibers produced in a compact-spinning process were studied by differential scanning calorimetry (DSC). With unrestrained fibers, the onset of melting increases with decreasing draw ratio, increasing Mw/Mn, decreasing extrusion temperature, increasing annealing ratio, and increasing draw-down ratio. These trends are discussed in terms of restraints and reorganization. The onset of melting is shifted to lower temperatures as the heating rate increases for all combinations of material and processing parameters, indicating suppressed reorganization. At low draw ratios, the height and width of the endotherm are affected by the spinline stress, and a secondary peak or shoulder is observed on the high temperature side of the main peak. The magnitude of the secondary peak increases with decreasing Mw/Mn, increasing draw ratio, decreasing draw-down ratio, and decreasing heating rate, but its position mainly depends on the heating rate. This indicates that the secondary peak may be due to the melting of structures that have been reorganized during the heating scan. As the draw ratio increases, the melting regime broadens, especially towards lower temperatures, and several maxima emerge on the DSC curve. Reorganization and shrinkage during heating may explain these observations. © 1995 John Wiley & Sons, Inc. 相似文献
36.
Reviewed and critiqued the relevance of the DSM-III-R for school psychological practice. Five misguided assumptions on which the use of the DSM-III-R system is based are presented. These assumptions deal with (1) medical model conceptualization of behavior, (2) reliability, (3) validity, (4) relevance for special education placement, and (5) treatment validity. Based on a critical analysis of each assumption, it was concluded that the DSM-III-R is largely irrelevant for the practice of school psychology. The absence of treatment validity was judged to be the most substantial deficit of the DSM-III-R. An alternative classification system based on a functional analysis of behavior was proposed as being more relevant for assessment, classification, placement, and intervention with students who are behaviorally disordered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
Hill Clara E.; Nutt-Williams Elizabeth; Heaton Kristin J.; Thompson Barbara J.; Rhodes Renee H. 《Canadian Metallurgical Quarterly》1996,43(2):207
Twelve experienced therapists completed a questionnaire, and 8 of the 12 were then interviewed about their experiences with a therapeutic impasse that ended in the termination of therapy. Data were analyzed using a qualitative methodology. Results indicated that most of the clients were anxious and depressed with personality disorders and interpersonal problems. Therapists perceived impasses as having a profound negative impact on both clients and therapists. Variables associated with impasses in a majority of the cases were a client history of interpersonal problems, a lack of agreement between therapists and clients about the tasks and goals of therapy, interference in the therapy by others, transference, possible therapist mistakes, and therapist personal issues. Implications for training, practice, and research are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
The purpose of this study was to determine the effect of load position in an internal frame backpack on physiological and perceptual variables. Ten female participants walked on a level treadmill for 10 min carrying 25% of their body weight in a high, central, or low position. The variables measured included oxygen consumption (VO2), heart rate (HR), respiratory exchange ratio (R), respiratory rate (RR), minute ventilation (VE), and rating of perceived exertion (RPE). VO2, VE, and RPE were significantly lower in the high position (18.6 +/- 2.3 ml/kg/min, 31.7 +/- 5.0 l/min, 2.8 +/- 0.8, respectively) compared to the low position (22.2 +/- 3.0 ml/kg/min, 38.6 +/- 7.5 l/min, 3.7 +/- 1.0, respectively). HR, R, and RR did not change significantly as the load was moved from the high (129.8 +/- 16.8, 0.89 +/- 0.06, 30.3 +/- 4.2, respectively) to the low position (136.0 +/- 25.3, 0.92 +/- 0.04, 33.8 +/- 5.2, respectively). The results of this study suggest that load placement is an important factor in the physiological and perceptual responses to load carriage, and that packing heavy items high in the backpack may be the most energy efficient method of carrying a load on the back. 相似文献
39.
Prior research has shown that those with alcohol problems have significantly elevated rates of traffic events (i.e. traffic violations and collisions) than licensed drivers from the general population and that treatment is associated with reductions in alcohol-related collisions. However, very little research exists on traffic events and the impact of treatment for cannabis or cocaine clients. The objectives of this research are: (1) to determine whether clients in treatment for a primary problem of alcohol, cannabis or cocaine have significantly elevated rates of traffic events than a matched control group of licensed drivers; and (2) to assess whether a significant reduction in traffic events occurs after treatment for each client group compared to a control group. Driver records of patients admitted to substance abuse treatment in 1994 for a primary problem of alcohol (n = 117), cannabis (n = 80) or cocaine (n = 169) were accessed from the Ministry of Transportation for Ontario, Canada. A comparison group of 504 licensed drivers frequency matched by age, sex and place of residence, was also randomly selected. Data was collapsed into two 6-year time periods: 1988-1993 (i.e. before treatment) and 1995-2000 (i.e. after treatment). Six repeated measures analysis of variance tests were conducted where traffic violations and collisions of three treatment groups (i.e. alcohol, cannabis or cocaine) and a control group were compared before and after treatment. All three treatment groups had significantly more traffic violations than the control group and no significant interactions between time period and group membership were found. For collisions, there was a significant interaction between the alcohol and control groups and between the cocaine and control groups. The average number of collisions for the alcohol and cocaine groups decreased after completing treatment, whereas the number for the control group was stable over the same time periods. Neither the interaction term nor the between group effect was significant in the comparison of the cannabis and control groups. When rates of collisions were calculated based on the period that each driver had a valid license, the interaction term was still significant for the comparison of the alcohol and control groups but not for the cocaine and control groups. The results contribute to existing literature by demonstrating that cocaine and cannabis clients have a higher risk of traffic violations than matched controls and that reductions in collision risk was found after treatment for the alcohol and cocaine groups. More research is needed to better understand the reasons for the higher risk of traffic events and to determine reasons for declines. 相似文献
40.
Umphress Elizabeth E.; Smith-Crowe Kristin; Brief Arthur P.; Dietz Joerg; Watkins Marla Baskerville 《Canadian Metallurgical Quarterly》2007,92(2):396
Although similarity-attraction notions suggest that similarity--for example, in terms of values, personality, and demography--attracts, the authors found that sometimes demographic similarity attracts and sometimes it repels. Consistent with social dominance theory (J. Sidanius & F. Pratto, 1999), they demonstrated in 3 studies that when prospective employees supported group-based social hierarchies (i.e., were high in social dominance orientation), those in high-status groups were attracted to demographic similarity within an organization, whereas those in low-status groups were repelled by it. An important theoretical implication of the findings is that social dominance theory and traditional similarity-attraction notions together help explain a more complex relationship between demographic similarity and attraction than was previously acknowledged in the organizational literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献